Hypofractionated Radiotherapy-Related Lymphopenia Is Associated With Worse Survival in Unresectable Intrahepatic Cholangiocarcinoma

OBJECTIVE

The aim of this study was to evaluate the incidence of radiotherapy (RT)-related lymphopenia, its predictors, and association with survival in unresectable intrahepatic cholangiocarcinoma (ICC) treated with hypofractionated-RT (HF-RT).

METHODS

Retrospective analysis of 96 patients with unresectable ICC who underwent HF-RT (median 58.05 Gy in 15 fractions) between 2009 and 2022 was performed. Absolute lymphocyte count (ALC) nadir within 12 weeks of RT was analyzed. Primary variable of interest was severe lymphopenia, defined as Grade 3+ (ALC <0.5 k/μL) per CTCAE v5.0. Primary outcome of interest was overall survival (OS) from RT.

RESULTS

Median follow-up was 16 months. Fifty-two percent of patients had chemotherapy pre-RT, 23% during RT, and 40% post-RT. Pre-RT, median ALC was 1.1 k/μL and 5% had severe lymphopenia. Post-RT, 68% developed RT-related severe lymphopenia. Patients who developed severe lymphopenia had a significantly lower pre-RT ALC (median 1.1 vs. 1.5 k/μL, P=0.01) and larger target tumor volume (median 125 vs. 62 cm3, P=0.02). In our multivariable Cox model, severe lymphopenia was associated with a 1.7-fold increased risk of death (P=0.04); 1-year OS rates were 63% vs 77% (P=0.03). Receipt of photon versus proton-based RT (OR=3.50, P=0.02), higher mean liver dose (OR=1.19, P<0.01), and longer RT duration (OR=1.49, P=0.02) predicted severe lymphopenia.

CONCLUSIONS

HF-RT-related lymphopenia is an independent prognostic factor for survival in patients with unresectable ICC. Patients with lower baseline ALC and larger tumor volume may be at increased risk, and use of proton therapy, minimizing mean liver dose, and avoiding treatment breaks may reduce RT-related lymphopenia.

Portal Vein or Superior Mesenteric Vein Thrombosis with Dose-Escalated Radiation for Borderline or Locally Advanced Pancreatic Cancer

PURPOSE

Portal vein and superior mesenteric vein thrombosis (PVT/SMVT) are potentially morbid complications of radiation dose-escalated local therapy for pancreatic cancer. We retrospectively reviewed records for patients treated with and without intraoperative radiation (IORT) to identify risk factors for PVT/SMVT.

METHODS

Ninety-six patients with locally advanced or borderline resectable pancreatic adenocarcinoma received neoadjuvant therapy followed by surgical exploration from 2009 to 2014. Patients at risk for close or positive surgical margins received IORT boost to a biologically effective dose (BED10) > 100. Prognostic factors for PVT/SMVT were evaluated using competing risks regression.

RESULTS

Median follow-up was 79 months for surviving patients. Fifty-six patients (58%) received IORT. Twenty-nine patients (30%) developed PVT/SMVT at a median time of 18 months. On univariate competing risks regression, operative blood loss and venous repair with a vascular interposition graft, but not IORT dose escalation or diabetes history, were significantly associated with PVT/SMVT. The development of thrombosis in the absence of recurrence was significantly associated with a longstanding diabetes history, post-neoadjuvant treatment CA19-9, and operative blood loss. All 4 patients who underwent both IORT and vascular repair with a graft developed PVT/SMVT. PVT/SMVT in the absence of recurrence is not associated with significantly worsened overall survival but led to frequent medical interventions.

CONCLUSIONS

Approximately 30% of patients who underwent neoadjuvant chemoradiation for PDAC developed PVT/SMVT a median of 18 months following surgery. This was significantly associated with venous reconstruction with vascular grafts, but not with escalating radiation dose. PVT/SMVT in the absence of recurrence was associated with significant morbidity.

Patient-Reported Outcomes, Tumor Markers, and Survival Outcomes in Advanced GI Cancer

Importance

Patient-reported outcomes (PROs), such as quality of life (QOL) and symptoms, are often associated with clinical outcomes in patients with cancer. In practice, oncologists use serum tumor markers (TMs) (ie, carcinoembryonic antigen [CEA] and carbohydrate antigen 19-9 [CA 19-9]) and imaging to monitor clinical outcomes in patients with gastrointestinal cancer.

Objective

To examine associations of 1-month changes in PROs and TMs with treatment response and survival among patients with gastrointestinal cancer.

Design, Setting, and Participants

This cohort study enrolled patients at Massachusetts General Hospital Cancer Center with at least 1 month follow-up from May 2019 to December 2020. Included patients were beginning first-line systemic therapy, aged 18 years or older, and had been diagnosed with metastatic pancreaticobiliary, colorectal, or gastroesophageal cancer. Data analyses took place from January 2021 to January 2022.

Intervention

PROs were collected, including QOL (Functional Assessment of Cancer Therapy General [FACT-G]), physical symptoms (Edmonton Symptom Assessment System [ESAS]), and psychological symptoms (Patient Health Questionnaire-4 [PHQ4] total, PHQ4-depression, and PHQ4-anxiety), as well as TMs (CEA and CA 19-9), at the time of chemotherapy initiation and 1 month later.

Main Outcomes and Measures

Associations of 1-month changes in PROs and TMs with treatment response (clinical benefit vs disease progression) at first scan, progression-free survival (PFS), and overall survival (OS), adjusted for baseline values using regression models.

Results

This study included 159 patients, with 134 patients (84.3%) evaluable for analysis. Patients had a median (range) age of 64.0 (28.0-84.0) years and 86 (64.2%) were male. One-month PRO changes (FACT-G: OR, 1.07; 95% CI, 1.03-1.11; P = .001; ESAS-total: OR, 0.97; 95% CI, 0.94-1.00; P = .02; ESAS-physical: OR, 0.96; 95% CI, 0.92-1.00; P = .03; PHQ4-depression: OR, 0.67; 95% CI, 0.49-0.92; P = .01) were significantly associated with treatment response, but PHQ4-total or TMs were not. Changes in FACT-G (HR, 0.97; 95% CI, 0.95-0.99; P = .003), ESAS-total (HR, 1.03; 95% CI, 1.01-1.05; P = .004), ESAS-physical (HR, 1.03; 95% CI, 1.00-1.05; P = .02), PHQ4-depression (HR, 1.22; 95% CI, 1.01-1.48; P = .04), and CEA (HR, 1.00; 95% CI, 1.001-1.004; P = .001) were associated with PFS, but changes in PHQ4-total or TMs were not. Changes in ESAS-total (HR, 1.03, 95% CI, 1.01-1.06; P = .006) and ESAS-physical (HR, 1.04, 95% CI, 1.01-1.06; P = .015) were associated with OS, but changes in TMs were not associated with OS.

Conclusions and Relevance

These findings suggest that 1-month changes in PROs can be associated with treatment response and survival in patients with advanced gastrointestinal cancer. Notably, 1-month changes in TMs were not consistently associated with these outcomes. These findings highlight the potential for monitoring early changes in PROs to associate with clinical outcomes while underscoring the need to address the QOL and symptom concerns of patients with advanced cancer.

Feasibility, Safety, and Efficacy of Aggressive Multimodal Management of Elderly Patients with Pancreatic Ductal Adenocarcinoma

OBJECTIVE

We aimed to evaluate the safety and efficacy of NAT followed by surgical resection in patients with PDAC aged ≥75 years.

SUMMARY BACKGROUND DATA

Whether administration of neoadjuvant therapy (NAT) followed by surgical resection in elderly patients with pancreatic ductal adenocarcinoma (PDAC) is safe and effective is unknown.

METHODS

The present study is a three-part comparison of older (≥ 75 years) versus younger (< 75 years) patients in different settings throughout the continuum of PDAC care. The first analysis was a comparison of older versus younger consecutive patients with non-metastatic PDAC who were initiated on FOLFIRINOX. The second was a comparison of older vs. younger patients who underwent NAT followed by surgical resection, and the third and final analysis was a comparison of older patients who underwent either NAT followed by surgical resection vs. upfront surgical resection. Postoperative complications, overall survival (OS), and time to recurrence (TTR), were compared. Propensity-score matching (PSM) analysis was performed to adjust for potential confounders.

RESULTS

In the first analysis, a lower proportion of older patients (n=40) were able to complete the intended neoadjuvant FOLFIRINOX (8) cycles compared to younger patients (n=214) (65.0% vs. 81.4%, P=0.021). However, older patients were just as likely to undergo surgical exploration as younger patients (77.5% vs 78.5%, P=0.89) as well as surgical resection (57.5% vs 55.6%, P=0.70). In the second analysis, PSM was conducted to compare older (n=54) vs. younger patients (n=54) who underwent NAT followed by surgical resection. There were no significant differences in postoperative complications between the matched groups. While there was a significant difference in overall survival (OS) between older and younger patients (median OS: 16.43 months vs. 30.83 months, P=0.002), importantly, there was no significant difference in time to recurrence (TTR, median: 7.65 months vs. 11.83 months, P=0.215). In the third analysis, older patients who underwent NAT followed by surgical resection (n=48) were compared with similar older patients who underwent upfront surgical resection (n=48). After PSM, there was a significant difference in OS (median OS: 15.78 months vs. 11.51 months, P=0.037) as well as TTR (median TTR: 8.81 months vs. 7.10 months, P=0.046) representing an association with improved outcomes that favored the neoadjuvant approach among older patients alone.

CONCLUSIONS

This comprehensive three-part study showed that administration of NAT followed by surgical resection appears to be safe and effective among patients ≥ 75 years of age. An aggressive approach should be offered to older adults undergoing multimodal treatment of PDAC.

Association between Liver Metastases and Treatment Response in Patients with Metastatic, Microsatellite Stable Colorectal Cancer Treated with Radiation Therapy and Dual Immune Checkpoint Blockade

PURPOSE/OBJECTIVE(S)

Most patients with metastatic colorectal cancer (CRC) have microsatellite stable (MSS) disease with a limited response to immune checkpoint inhibitors (ICIs). In our phase 2 trial (NCT03104439), 27 patients with metastatic MSS CRC received ipilimumab, nivolumab, and RT (24 Gy/3 fractions) on C2D1 with a disease control rate (DCR) of 37% (10/27) and overall response rate (ORR) of 15% (4/27). Our follow up phase 2 study with ipilimumab, nivolumab, and RT moved to C1D1 (NCT04361162) showed a DCR of 33% (10/30) and an ORR of 13% (4/30). Clinical and preclinical data suggest liver metastases are less responsive to systemic ICIs and complementary liver-directed RT can potentially overcome this effect. To address this, we investigated the association between liver metastases and response rates among patients treated with and without liver-directed RT in a pooled analysis of our phase 2 studies of nivolumab and ipilimumab with RT.

MATERIALS/METHODS

In this pooled secondary analysis of two open-label, single-arm, phase 2 studies, eligible patients had metastatic MSS CRC, ECOG PS 0-1, and progressed on at least one line of chemotherapy. Treatment consisted of ipilimumab 1 mg/kg q6weeks for 4 cycles, nivolumab 240 mg q2weeks on a 6-week cycle, and RT (24 Gy/3 fractions) on C1D1 or C2D1 to one site. Responses were defined outside of the RT field by RECIST 1.1 with centrally reviewed imaging q3months. ORR/DCR and PFS/OS were compared between patients with and without liver metastases with the Fisher's exact and log-rank tests, respectively. P-values are two-sided.

RESULTS

We treated 57 patients (median age 57 years [range, 26-85], 61% male, 88% white, 65% with liver metastases) from 07/2017 to 05/2022. Patients received a median of 3 (range, 1-10) prior lines of systemic therapy. The combined ORR was 14% (8/57; 95% CI, 6-26%) and DCR was 35% (20/57; 95% CI, 23-49%). The ORR was 30% (6/20; 95% CI, 12-54%) in patients without liver metastases and 5% (2/37; 95% CI, 1-18%) in patients with liver metastases (p = 0.017). The DCR was 55% (11/20; 95% CI, 32-77%) in patients without liver metastases and 24% (9/37; 94% CI, 12-41%) in patients with liver metastases (p = 0.040). 76% (28/37) of patients with liver metastases received liver-directed RT including 2/2 (100%) patients with a PR. The ORR was 0% in patients with liver metastases without liver-directed RT. The median PFS was 1.8 months (95% CI, 1.2-2.4 months) and OS was 9.8 months (95% CI, 6.8-12.8). OS was longer in patients without liver metastases (median 13.6 v 6.8 months, p = 0.010) and in patients treated with liver-directed RT among those with liver metastases (median 7.5 months v 4.5 months, p = 0.025).

CONCLUSION

Among patients with metastatic MSS CRC treated with ICIs and RT in two phase 2 studies, ORR, DCR, and OS are significantly higher in patients without liver metastases. Liver-directed RT may improve ICI efficacy and OS in patients with liver metastases. Further analysis of PFS and prospective study of ICIs with comprehensive liver-directed RT are warranted.

Tolerability, Attrition Rates, and Survival Outcomes of Neoadjuvant FOLFIRINOX for Nonmetastatic Pancreatic Adenocarcinoma: Intent-to-Treat Analysis

BACKGROUND

FOLFIRINOX is increasingly used in the management of pancreatic ductal adenocarcinoma (PDAC). However, neoadjuvant therapy is associated with toxicity, possible disease progression, and biopsy-related and biliary complications that may preclude operative exploration. Data on the true attrition rate outside of clinical trials or resected surgical series are lacking.

STUDY DESIGN

Patients with nonmetastatic PDAC who initiated FOLFIRINOX from 2015 to 2020 were identified from our institution's pharmacy records. Multivariable regression and Cox proportional hazard models were used for adjusted analyses of categorical and survival outcomes, respectively.

RESULTS

Of 254 patients who initiated first-line neoadjuvant FOLFIRINOX, 199 (78.3%) underwent exploration, and 54 (21.3%) did not complete their chemotherapy cycles due to poor tolerability (46.3%), poor response (31.5%), or disease progression (14.8%), among other causes (7.4%). A total of 109 (42.9%) patients experienced grade 3/4 FOLFIRINOX-related toxicity, of whom 73 (28.7%) and 100 (39.4%) required an emergency department visit or inpatient admission, respectively. Finally, not undergoing surgical exploration was associated with impaired overall survival (hazard ratio 7.0; 95% CI 3.8 to 12.8; p < 0.001). Independent predictors of not undergoing exploration were remote history of chemotherapy receipt (odds ratio [OR] 0.06; p = 0.02), inability to complete FOLFIRINOX cycles (OR 0.2, p = 0.003), increase in ECOG score (OR 0.2, p < 0.001), and being single or divorced (OR 0.3, p = 0.018).

CONCLUSIONS

Among 254 patients with nonmetastatic PDAC initiated on FOLFIRINOX, of whom 52% were locally advanced, a total of 199 (78.3%) were explored, 142 (71.4%) underwent successful resection, and 129 (90.8%) were resected with negative margins. Despite 109 (42.9)% of patients experiencing significant toxicity, most patients could be managed through treatment-related complications to complete planned neoadjuvant chemotherapy and undergo planned surgical exploration.

Assessment of complete pathologic response after neoadjuvant immunotherapy for MSI-H gastrointestinal cancers

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Background: Immunotherapy (IO) has shown remarkable efficacy in gastrointestinal (GI) cancers with high microsatellite instability (MSI-H). We evaluated real world outcomes of patients treated with neoadjuvant IO for MSI-H colorectal (CRC) and gastroesophageal (GE) cancers. Methods: We queried diagnoses, pathology reports, and clinic notes of patients receiving IO at Massachusetts General Hospital from October 2014 to March 2022 using the Research Patient Data Registry and MATLAB. 1140 patients were identified with esophageal, gastric, colon, or rectal primaries. Of these, 56 were MSI-H and seven received neoadjuvant IO with curative intent. Results: Of the seven patients who received neoadjuvant IO for MSI-H CRC or GE cancers, three patients achieved complete pathologic response (pCR). Three patients had partial responses; one had a single residual lymph node tumor cell, one had residual T1b tumor and negative nodes, and one had residual T3 tumor and positive nodes. All patients with pCR had non-metastatic disease. Three of four patients with partial responses or progression had metastatic disease. Five patients had no recurrence by median follow-up of 10 months post-resection. One patient's cancer recurred 15 months post-resection, and one patient had progressive disease on neoadjuvant IO so did not undergo primary resection. Conclusions: Neoadjuvant IO shows promise for MSI-H GI cancers. Three of seven patients (43%) had pCR and three others (43%) had notable partial responses. There is a need to understand IO-refractory primary tumors and the differing effects of IO in local versus metastatic disease. While our data is limited by sample size, larger clinical trials can establish the safety and utility of neoadjuvant IO, potentially sparing many patients from surgery. We will collaborate with other centers for a larger scale analysis on neoadjuvant IO in MSI-H GI cancers. [Table: see text]

A multicenter, randomized phase II study of total neoadjuvant therapy (TNT) with FOLFIRINOX (FFX) and SBRT, with or without losartan (L) and nivolumab (N) in borderline resectable (BR) and locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC)

719

Background: Outcomes in BR and LA PDAC remain historically poor, in part due to low rates of R0 resection. A prior phase II study demonstrated that losartan (L) as a TGF-beta inhibitor combined with FOLFIRINOX (FFX) and radiation in LA PDAC led to a 61% R0 resection rate. Additionally, prior phase II studies suggest potential synergy with SBRT and nivolumab (N) in PDAC. We conducted a multi-center, randomized phase II trial to evaluate the effect of L and L+N in combination with TNT using FFX and SBRT. Methods: Patients with BR or LA PDAC by NCCN criteria, pathologically confirmed, ACE/ARB naïve, were randomized to TNT with FFX and SBRT (Arm 1), TNT + L (Arm 2), and TNT+L+N (Arm 3), stratified by BR/LA. Patients already on an ACE or ARB were enrolled on an exploratory arm of TNT+N (Arm 4) and will be reported separately. TNT consisted of FFX x 8 followed by SBRT (6.6 Gy x 5). L was given at 50 mg qd throughout TNT and for 6 mo after surgery. N was given at 240 mg flat dosing q2 wks concurrent with SBRT and for 12 doses postoperatively. All patients were recommended for surgical exploration after TNT. The study was designed to compare the R0 resection rate on each of Arms 2 and 3 independently versus Arm 1 at a one-sided 0.10 level. Secondary endpoints were PFS, OS, and pCR rates and analyzed using two-sided tests with Arm 1 as the control arm. Intent-to-treat analysis was based on eligible patients who started therapy on protocol. Results: Patients with BR or LA PDAC by NCCN criteria, pathologically confirmed, ACE/ARB naïve, were randomized to TNT with FFX and SBRT (Arm 1), TNT + L (Arm 2), and TNT+L+N (Arm 3), stratified by BR/LA. Patients already on an ACE or ARB were enrolled on an exploratory arm of TNT+N (Arm 4) and will be reported separately. TNT consisted of FFX x 8 followed by SBRT (6.6 Gy x 5). L was given at 50 mg qd throughout TNT and for 6 mo after surgery. N was given at 240 mg flat dosing q2 wks concurrent with SBRT and for 12 doses postoperatively. All patients were recommended for surgical exploration after TNT. The study was designed to compare the R0 resection rate on each of Arms 2 and 3 independently versus Arm 1 at a one-sided 0.10 level. Secondary endpoints were PFS, OS, and pCR rates and analyzed using two-sided tests with Arm 1 as the control arm. Intent-to-treat analysis was based on eligible patients who started therapy on protocol. Conclusions: We did not observe effects of L and L+N on the R0 resection rate, PFS, OS, and pCR rate when added to TNT with FFX and SBRT for BR or LA PDAC. The lack of differences may reflect heterogeneity in surgical opinion as the decision for proceeding to surgery following TNT tends to be highly variable in a population with historically low resection rates. Clinical trial information: NCT03563248 .

Combined PD-1, BRAF and MEK inhibition in BRAFV600E colorectal cancer: a phase 2 trial

While BRAF inhibitor combinations with EGFR and/or MEK inhibitors have improved clinical efficacy in BRAFV600E colorectal cancer (CRC), response rates remain low and lack durability. Preclinical data suggest that BRAF/MAPK pathway inhibition may augment the tumor immune response. We performed a proof-of-concept single-arm phase 2 clinical trial of combined PD-1, BRAF and MEK inhibition with sparatlizumab (PDR001), dabrafenib and trametinib in 37 patients with BRAFV600E CRC. The primary end point was overall response rate, and the secondary end points were progression-free survival, disease control rate, duration of response and overall survival. The study met its primary end point with a confirmed response rate (24.3% in all patients; 25% in microsatellite stable patients) and durability that were favorable relative to historical controls of BRAF-targeted combinations alone. Single-cell RNA sequencing of 23 paired pretreatment and day 15 on-treatment tumor biopsies revealed greater induction of tumor cell-intrinsic immune programs and more complete MAPK inhibition in patients with better clinical outcome. Immune program induction in matched patient-derived organoids correlated with the degree of MAPK inhibition. These data suggest a potential tumor cell-intrinsic mechanism of cooperativity between MAPK inhibition and immune response, warranting further clinical evaluation of optimized targeted and immune combinations in CRC. ClinicalTrials.gov registration: NCT03668431.

Prospective Phase II Trials Validate the Effect of Neoadjuvant Chemotherapy on Pattern of Recurrence in Pancreatic Adenocarcinoma

OBJECTIVE

The objective of this study was to characterize the patterns of first recurrence after curative-intent resection for pancreatic adenocarcinoma (PDAC).

SUMMARY OF BACKGROUND DATA

We evaluated the first site of recurrence after neoadjuvant treatment as locoregional (LR) or distant metastasis (DM). To validate our findings, we evaluated the pattern from 2 phase II clinical trials evaluating neoadjuvant chemotherapy (NAC) in PDAC.

METHODS

We identified site of first recurrence from a retrospective cohort of patients from 2011 to 2017 treated with NAC followed by chemoradiation and then an operation or an operation first followed by adjuvant therapy, and 2 separate prospective cohorts of patients derived from 2 phase II clinical trials evaluating patients treated with NAC in borderline-resectable and locally advanced PDAC.

RESULTS

In the retrospective cohorts, 160 out of 285 patients (56.1%) recurred after a median disease-free survival (mDFS) of 17.2 months. The pattern of recurrence was DM in 81.9% of patients, versus LR in 11.1%. This pattern was consistent in patients treated with upfront resection and adjuvant chemotherapy (DM 83.0%, LR 16.9%) regardless of margin-involvement (DM 80.1%, LR 19.4%). The use of NAC did not alter pattern of recurrence; 81.7% had DM and 18.3% had LR. This pattern also remained consistent regardless of margin-involvement (DM 94.1%, LR 5.9%). In the Phase II borderline-resectable trial (NCI# 01591733) cohort of 32 patients, the mDFS was 34.2 months. Pattern of recurrence remained predominantly DM (88.9%) versus LR (11.1%). In the Phase II locally-advanced trial (NCI# 01821729) cohort of 34 patients, the mDFS was 30.7 months. Although there was a higher rate of local recurrence in this cohort, pattern of first recurrence remained predominantly DM (66.6%) versus LR (33.3%) and remained consistent independent of margin-status.

CONCLUSIONS

The pattern of recurrence in PDAC is predominantly DM rather than LR, and is consistent regardless of the use of NAC and margin involvement.

Supportive Oncology Care at Home Intervention for Patients With Pancreatic Cancer

PURPOSE

We sought to determine the feasibility of delivering a Supportive Oncology Care at Home intervention among patients with pancreatic cancer.

METHODS

We prospectively enrolled patients with pancreatic cancer from a parent trial of neoadjuvant fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFIRINOX). The intervention entailed (1) remote monitoring of patient-reported symptoms, vital signs, and body weight; (2) a hospital-at-home care model; and (3) structured communication with the oncology team. We defined the intervention as feasible if ≥ 60% of patients enrolled in the study and ≥ 60% completed the daily assessments within the first 2-weeks of enrollment. We determined rates of treatment delays, urgent clinic visits, emergency department visits, and hospitalizations among those who did (n = 20) and did not (n = 24) receive Supportive Oncology Care at Home from the parent trial.

RESULTS

From January 2019 to September 2020, we enrolled 80.8% (21/26) of potentially eligible patients. One patient became ineligible following consent because of moving out of state, resulting in 20 participants (median age = 67 years). In the first 2 weeks of enrollment, 65.0% of participants completed all daily assessments. Overall, patients reported 96.1% of daily symptoms, 96.1% of daily vital signs, and 92.5% of weekly body weights. Patients receiving the intervention had lower rates of treatment delays (55.0% v 75.0%), urgent clinic visits (10.0% v 25.0%), and emergency department visits/hospitalizations (45.0% v 62.5%) compared with those not receiving the intervention from the same parent trial.

CONCLUSION

Findings demonstrate the feasibility and acceptability of a Supportive Oncology Care at Home intervention. Future work will investigate the efficacy of this intervention for decreasing health care use and improving patient outcomes.

Reverse Transcriptase Inhibition Disrupts Repeat Element Life Cycle in Colorectal Cancer

Altered RNA expression of repetitive sequences and retrotransposition are frequently seen in colorectal cancer, implicating a functional importance of repeat activity in cancer progression. We show the nucleoside reverse transcriptase inhibitor 3TC targets activities of these repeat elements in colorectal cancer preclinical models with a preferential effect in p53-mutant cell lines linked with direct binding of p53 to repeat elements. We translate these findings to a human phase II trial of single-agent 3TC treatment in metastatic colorectal cancer with demonstration of clinical benefit in 9 of 32 patients. Analysis of 3TC effects on colorectal cancer tumorspheres demonstrates accumulation of immunogenic RNA:DNA hybrids linked with induction of interferon response genes and DNA damage response. Epigenetic and DNA-damaging agents induce repeat RNAs and have enhanced cytotoxicity with 3TC. These findings identify a vulnerability in colorectal cancer by targeting the viral mimicry of repeat elements.

SIGNIFICANCE

Colorectal cancers express abundant repeat elements that have a viral-like life cycle that can be therapeutically targeted with nucleoside reverse transcriptase inhibitors (NRTI) commonly used for viral diseases. NRTIs induce DNA damage and interferon response that provide a new anticancer therapeutic strategy. This article is highlighted in the In This Issue feature, p. 1397.

Changes in Functional Assessment of Cancer Therapy: General (FACT-G) to predict treatment response and survival outcomes in patients with metastatic gastrointestinal (GI) cancer

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Background: The FACT-G contains 27 questions within 4 subscale domains [Physical Well-Being, Social/Family Well-Being, Emotional Well-Being, Functional Well-Being] related to health-related quality of life (QOL) in the past 7 days, with higher scoring indicating better QOL. In this prospective cohort study, we assessed longitudinal FACT-G data with treatment response and survival outcomes among patients with metastatic GI cancer. Methods: From 5/2019-11/2021, we enrolled patients at Massachusetts General Hospital with metastatic GI cancer to study before their treatment start. We collected the FACT-G survey at baseline (start of treatment) and 1-month later. We then used regression models to assess associations of 1-month changes in FACT-G with treatment response and survival outcomes (progression-free survival [PFS] and overall survival [OS]). For treatment response, clinical benefit was defined as decreased or stable tumor burden versus progressive disease at the time of first scan. All models were adjusted for baseline values of each respective variable. Results: We enrolled 203 of 262 patients approached (77.5% enrollment); 160 had 1-month follow-up data (median age = 63.0 years [range: 28.0-84.0 years], 66.3% male, 45.6% pancreaticobiliary cancer). For treatment response, 66.3% experienced a clinical benefit and 33.8% had progressive disease at the time of first scan (mean time to first scan = 2.7 months). Increases in FACT-G Total were predictors for treatment response (OR = 1.05, p = 0.0028), and improved PFS (HR = 0.98, p = 0.026) and OS (HR = 0.98, p = 0.038). Increases in FACT-G Emotional were associated with clinical benefit at the time of first scan (OR = 1.18, p = 0.0024), improved PFS (HR = 0.94, p = 0.023), and improved OS (HR = 0.93, p = 0.012). Improvement in FACT-G Physical were predictors for clinical benefit at time of first scan (OR = 1.08, p = 0.038) and better PFS (HR = 0.96, p = 0.038), while increases in FACT-G Functional were associated with improved PFS (HR = 0.96, p = 0.034) and OS (HR = 0.96, p = 0.019). Finally, changes in FACT-G Social were only associated with treatment response (OR = 1.16, p = 0.011). Conclusions: We found that 1-month increases in FACT-G can predict for treatment response and improved survival outcomes in patients with metastatic GI cancers. Notably, the FACT-G Total and FACT-G Emotional subscore predicted for all three outcomes of interest, while the FACT-G Social only predicted for clinical benefit at first scan. These data support previous findings indicating the possible use of early changes in patient-reported outcomes as a biomarker for early treatment response while emphasizing the growing need to integrate more patient-centric interventions into clinical care for cancer patients. Clinical trial information: NCT04776837.

A phase II study of niraparib and dostarlimab with radiation in patients with metastatic pancreatic cancer

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Background: PARP inhibitors have activity as monotherapy in BRCA1/2 mutated metastatic pancreatic cancer; however, several other genes and associated proteins exist in the homologous recombination repair (HRR) pathway promoting resistance to chemotherapy and radiation-induced damage. Tumors with HRR deficiency have an impaired ability to repair themselves and are susceptible to PARP inhibition, but ionizing radiation can also induce DNA breaks. Ongoing research suggests that PARP inhibitors may cause radio-sensitization and may also enhance sensitivity to immunotherapy. We conducted a phase 2 study of niraparib and dostarlimab with radiation in a biomarker unselected PDAC population given PARP inhibitors' immunomodulatory and radiosensitizing effects. Methods: In this open-label, single-arm, phase-2 study, eligible patients had histologically confirmed MSS PDAC, ECOG PS 0-1, and progressed on at least one line of jm. Treatment consisted of niraparib 200 mg daily on a 21-day cycle, dostarlimab 500 mg every 3 weeks every 4 weeks for the first four doses, then 1000 mg every 6 weeks, and 3 fractions of 8 Gy at Cycle 2. Treatment continued until progressive disease, discontinuation, or withdrawal. The primary endpoint was DCR by RECIST 1.1 with radiological evaluations every 3 months. Secondary endpoints included DCR by irRECIST, PFS, OS, and safety. Responses were defined as disease control outside the radiation field. We obtained serial tumor biopsies, including pre-treatment. A two-stage design was used, requiring disease control in at least one of the first 15 patients before proceeding to the full accrual of 25 patients. Intention to treat analysis included all patients receiving at least one dose of any study agent. Results: We enrolled and treated 15 pts (median age 60 years [range 37-77], 53% male) from 08/2020 to 05/2021. Overall, DCR was 0/15 (95% CI: 0-22%), median PFS was 1.6 months (95% CI: 1.1-2.7), and median OS 3.1 months (95% CI: 1.5-7.7). Among 27 treatment-related serious adverse events, 15 (56%) were grade 3, including decreased CD4 lymphocytes, thrombocytopenia, anemia, and fatigue being the most common. Conclusions: The combination of niraparib and dostarlimab with radiation did not meet the pre-specified criteria for expansion to full accrual. Further analyses of dose intensity in this heavily pretreated and evaluation of in-field responses are underway. Further investigation of the combination with biomarker selection is warranted. Clinical trial information: NCT04409002.

Radiation therapy enhances immunotherapy response in microsatellite stable colorectal and pancreatic adenocarcinoma in a phase II trial

Overcoming intrinsic resistance to immune checkpoint blockade for microsatellite stable (MSS) colorectal cancer (CRC) and pancreatic ductal adenocarcinoma (PDAC) remains challenging. We conducted a single-arm, non-randomized, phase II trial (NCT03104439) combining radiation, ipilimumab and nivolumab to treat patients with metastatic MSS CRC (n = 40) and PDAC (n = 25) with an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. The primary endpoint was disease control rate (DCR) by intention to treat. DCRs were 25% for CRC (ten of 40; 95% confidence interval (CI), 13-41%) and 20% for PDAC (five of 25; 95% CI, 7-41%). In the per-protocol analysis, defined as receipt of radiation, DCR was 37% (ten of 27; 95% CI, 19-58%) in CRC and 29% (five of 17; 95% CI, 10-56%) in PDAC. Pretreatment biopsies revealed low tumor mutational burden for all samples but higher numbers of natural killer (NK) cells and expression of the HERVK repeat RNA in patients with disease control. This study provides proof of concept of combining radiation with immune checkpoint blockade in immunotherapy-resistant cancers.

Conditional Survival in Resected Pancreatic Ductal Adenocarcinoma Patients Treated with Total Neoadjuvant Therapy

BACKGROUND

Dynamic survival data based on time already survived are lacking for resected borderline resectable/locally advanced (BR/LA) pancreatic ductal adenocarcinoma (PDAC) patients who received total neoadjuvant therapy (TNT) with FOLFIRINOX followed by chemoradiation. Conditional survival, i.e., the probability of surviving an additional length of time after having already survived an amount of time, offers such information. We aimed to determine actuarial and conditional overall (OS, COS) and disease-free survival (DFS, CDFS) among this cohort.

METHODS

Clinicopathologic data were retrospectively collected for resected BR/LA PDAC patients who received TNT (2011-2019). COS and CDFS rates were calculated for patients being event (death/recurrence)-free at multiple intervals and by recurrence status.

RESULTS

After a median follow-up of 32.1 months, the 183 patients had a median OS and DFS of 39.1 months and 16.8 months, respectively. COS and CDFS increased as a function of time already survived. The probability of surviving an additional 24 months if a patient survived 2 years post-operatively was 70%, whereas the 4-year actuarial OS was 47%. Similarly, the probability of surviving disease-free an additional 24 months after 2 years was 66%, while actuarial 48-month DFS was 27%. COS for disease-free patients increased further over time. For patients remaining disease-free 12 months post-operatively, BR vs. LA status at diagnosis, tumor ≤ 4 cm at diagnosis, and R0 resection were independent predictors of favorable additional OS and DFS.

CONCLUSIONS

For resected TNT-treated BR/LA PDAC patients, the probability of surviving an additional length of time increases as a function of survival already accrued. Dynamic survival estimates may allow personalized follow-up and counseling.

Supportive oncology care at home intervention for patients with pancreatic cancer

155

Background: Patients with pancreatic cancer receiving chemotherapy often experience substantial symptoms and high healthcare utilization. We sought to determine the feasibility of delivering a Supportive Oncology Care at Home intervention designed to address the needs of patients receiving treatment for pancreatic cancer. Methods: We prospectively enrolled patients with pancreatic cancer who were participating in a parent trial of neoadjuvant FOLFIRINOX and residing in-state, within 50 miles of our hospital. Patients received the Supportive Oncology Care at Home intervention during neoadjuvant treatment (i.e., up to 4 months). The intervention entailed: 1) remote monitoring of daily patient-reported symptoms, daily vital signs, and weekly body weight; 2) a hospital in the home care model for symptom assessment and management; and 3) structured communication with the oncology team. We defined the intervention as feasible if ≥60% of patients enrolled in the study and ≥60% completed the daily assessments within the first two weeks of enrollment. We tracked numbers of phone calls, emails, and home visits generated by the intervention. We conducted exit interviews with patients, caregivers, and oncology clinicians to assess the acceptability of the intervention. We also compared rates of treatment delays, urgent clinic visits, emergency room (ER) visits, and hospitalizations among those who did (n = 20) and did not (n = 24) receive Supportive Oncology Care at Home from the parent trial. Results: From 1/2019-9/2020, we enrolled 80.8% (21/26) of potentially eligible patients. One patient became ineligible following consent due to moving out-of-state, resulting in 20 participants (median age = 67 years [range 55-77]; 60.0% female). In the first two weeks of enrollment, 65.0% of participants completed all daily assessments. Overall, patients reported 96.1% of daily symptoms, 96.1% of daily vital signs, and 92.5% of weekly body weights. Each participant generated an average of 2.22 phone calls (range 0.62-3.77), 2.96 emails (range 1.50-5.88), and 0.15 home visits (range 0-0.69) per week. During exit interviews, > 80% of patients, caregivers, and clinicians found the intervention to be helpful and convenient, and they reported high satisfaction with the communication among patients, clinicians, and the hospital in the home team. Patients receiving the intervention had lower rates of treatment delays (55.0% v 75.0%), urgent clinic visits (10.0% v 25.0%), ER visits or hospitalizations (45.0% v 62.5%), as well as a lower proportion of days spent in urgent clinic, ER, or hospital (2.7% v 7.8%), compared with those not receiving the intervention who were in the same parent trial. Conclusions: These findings demonstrate the feasibility and acceptability of a Supportive Oncology Care at Home intervention. Future work will investigate the efficacy of this intervention for decreasing healthcare use and improving patient outcomes. Clinical trial information: NCT03798769.

Changes in patient-reported outcomes (PROs) and tumor markers (TMs) to predict treatment response and survival in patients with metastatic gastrointestinal (GI) cancer

154

Background: PROs assessing quality of life (QOL) and symptoms at a single timepoint frequently correlate with clinical outcomes in patients with cancer, yet efforts to understand how longitudinal changes in PROs can predict for treatment outcomes are lacking. In practice, oncologists often use changes in serum TMs (CEA and CA19-9) to monitor patients with GI cancer, and thus we sought to examine associations of 1-month changes in PROs and TMs with treatment response and survival outcomes among patients with advanced GI cancer. Methods: We prospectively enrolled patients with metastatic GI cancer prior to initiating chemotherapy at Massachusetts General Hospital from 5/2019-12/2020. At baseline (start of treatment) and 1-month later, we collected PROs (QOL [Functional Assessment of Cancer Therapy General {FACT-G}], physical symptoms [Edmonton Symptom Assessment System {ESAS}], and psychological symptoms [Patient Health Questionnaire-4 {PHQ-4}]) and TMs. We used regression models to examine associations of 1-month changes in PROs and TMs with treatment response (clinical benefit [defined as decreased or stable tumor burden] or progressive disease at the time of first scan) and survival outcomes (progression-free survival [PFS] and overall survival [OS]), adjusted for baseline values of each respective variable. Results: We enrolled 159 of 191 patients approached (83.2% enrollment); 134 had 1-month follow-up data (median age = 64 years [range: 28 to 84 years], 64.2% male, 46.3% pancreaticobiliary cancer). For treatment response, 63.4% had clinical benefit and 36.6% had progressive disease at the time of first scan (mean time to first scan = 2.01 months). Changes in PROs (ESAS-Total: OR = 0.97, p = 0.022; ESAS-Physical: OR = 0.96, p = 0.027; PHQ-4 depression: OR = 0.67, p = 0.014; FACT-G: OR = 1.07, p = 0.001), but not TMs (CEA: OR = 1.00, p = 0.836 and CA19-9: OR = 1.00, p = 0.796), were associated with clinical benefit at the time of first scan. Changes in ESAS-Total (HR = 1.03, p = 0.004), ESAS-Physical (HR = 1.03, p = 0.021), PHQ-4 depression (HR = 1.22, p = 0.042), FACT-G (HR = 0.97, p = 0.003), and CEA (HR = 1.00, p = 0.001) were predictors of PFS. Changes in ESAS-Total (HR = 1.03, p = 0.006) and ESAS-Physical (HR = 1.04, p = 0.015) were predictors of OS, but 1-month changes in TMs (CEA: HR = 1.00, p = 0.377 and CA19-9: HR = 1.00, p = 0.367) did not significantly predict for OS. Conclusions: We found that 1-month changes in PROs can predict for treatment response and survival outcomes in patients with advanced GI cancers. Notably, 1-month changes in CEA only correlated with PFS, while changes in CA19-9 did not significantly predict treatment response or survival outcomes. These findings highlight the potential for early changes in PROs to predict treatment outcomes while underscoring the need to monitor and address PROs in patients with advanced cancer. Clinical trial information: NCT04776837.

Neoadjuvant versus Postoperative Chemoradiotherapy is Associated with Improved Survival for Patients with Resectable Gastric and Gastroesophageal Cancer

BACKGROUND

The optimal timing of chemoradiotherapy (CRT) for patients with localized gastric cancer remains unclear. This study aimed to compare the survival outcomes between neoadjuvant and postoperative CRT for patients with gastric and gastroesophageal junction (GEJ) cancer.

METHODS

This retrospective study analyzed 152 patients with gastric (42%) or GEJ (58%) adenocarcinoma who underwent definitive surgical resection and received either neoadjuvant or postoperative CRT between 2005 and 2017 at the authors' institution. The primary end point of the study was overall survival (OS).

RESULTS

The median follow-up period was 37.5 months. Neoadjuvant CRT was performed for 102 patients (67%) and postoperative CRT for 50 patients (33%). The patients who received neoadjuvant CRT were more likely to be male and to have a GEJ tumor, positive lymph nodes, and a higher clinical stage. The median radiotherapy (RT) dose was 50.4 Gy for neoadjuvant RT and 45.0 Gy for postoperative RT (p < 0.001). The neoadjuvant CRT group had a pathologic complete response (pCR) rate of 26% and a greater rate of R0 resection than the postoperative CRT group (95% vs. 76%; p = 0.002). Neoadjuvant versus postoperative CRT was associated with a lower rate of any grade 3+ toxicity (10% vs. 54%; p < 0.001). The multivariable analysis of OS showed lower hazards of death to be independently associated neoadjuvant versus postoperative CRT (hazard ratio [HR] 0.57; 95% confidence interval [CI] 0.36-0.91; p = 0.020) and R0 resection (HR 0.50; 95% CI 0.27-0.90; p = 0.021).

CONCLUSIONS

Neoadjuvant CRT was associated with a longer OS, a higher rate of R0 resection, and a lower treatment-related toxicity than postoperative CRT. The findings suggest that neoadjuvant CRT is superior to postoperative CRT in the treatment of gastric and GEJ cancer.

Results and molecular correlates from a pilot study of neoadjuvant induction FOLFIRINOX followed by chemoradiation and surgery for gastroesophageal adenocarcinomas

PURPOSE

We performed a NCI-sponsored, prospective study of neoadjuvant FOLFIRINOX followed by chemoradiation (CRT) with carboplatin/paclitaxel followed by surgery in patients with locally advanced gastric or gastroesophageal (GEA) cancer.

EXPERIMENTAL DESIGN

The primary objective was to determine completion rate of neoadjuvant FOLFIRINOX x 8 followed by CRT. Secondary endpoints were toxicity and pathologic complete response (pCR) rate. Exploratory analysis was performed of ctDNA to treatment response.

RESULTS

From Oct 2017 to June 2018, 25 patients were enrolled. All patients started FOLFIRINOX, 92% completed all 8 planned cycles, and 88% completed CRT. Twenty (80%) patients underwent surgical resection, and 7 had a pCR (35% in resected cohort, 28% ITT ). Tumor-specific mutations were identified in 21 (84%) patients, of whom 4 and 17 patients had undetectable and detectable ctDNA at baseline, respectively. Presence of detectable post-CRT ctDNA (p=0.004) and/or postoperative ctDNA (p=0.045) were associated with disease recurrence.

CONCLUSIONS

Here we show neoadjuvant FOLFIRINOX followed by CRT for locally advanced GEA is feasible and yields a high rate of pCR. ctDNA appears to be a promising predictor of postoperative recurrence.

Tumor Microenvironment Immune Response in Pancreatic Ductal Adenocarcinoma Patients Treated With Neoadjuvant Therapy

BACKGROUND

Neoadjuvant folinic acid, fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) and chemoradiation have been used to downstage borderline and locally advanced pancreatic ductal adenocarcinoma (PDAC). Whether neoadjuvant therapy-induced tumor immune response contributes to the improved survival is unknown. Therefore, we evaluated whether neoadjuvant therapy induces an immune response towards PDAC.

METHODS

Clinicopathological variables were collected for surgically resected PDACs at the Massachusetts General Hospital (1998-2016). Neoadjuvant regimens included FOLFIRINOX with or without chemoradiation, proton chemoradiation (25 Gy), photon chemoradiation (50.4 Gy), or no neoadjuvant therapy. Human leukocyte antigen (HLA) class I and II expression and immune cell infiltration (CD4+, FoxP3+, CD8+, granzyme B+ cells, and M2 macrophages) were analyzed immunohistochemically and correlated with clinicopathologic variables. The antitumor immune response was compared among neoadjuvant therapy regimens. All statistical tests were 2-sided.

RESULTS

Two hundred forty-eight PDAC patients were included. The median age was 64 years and 50.0% were female. HLA-A defects were less frequent in the FOLFIRINOX cohort (P = .006). HLA class II expression was lowest in photon and highest in proton patients (P = .02). The FOLFIRINOX cohort exhibited the densest CD8+ cell infiltration (P < .001). FOLFIRINOX and proton patients had the highest CD4+ and lowest T regulatory (FoxP3+) cell density, respectively. M2 macrophage density was statistically significantly higher in the treatment-naïve group (P < .001) in which dense M2 macrophage infiltration was an independent predictor of poor overall survival.

CONCLUSIONS

Neoadjuvant FOLFIRINOX with or without chemoradiation may induce immunologically relevant changes in the tumor microenvironment. It may reduce HLA-A defects, increase CD8+ cell density, and decrease T regulatory cell and M2 macrophage density. Therefore, neoadjuvant FOLFIRINOX therapy may benefit from combinations with checkpoint inhibitors, which can enhance patients' antitumor immune response.

Care Patterns and Overall Survival in Patients With Early-Onset Metastatic Colorectal Cancer

PURPOSE

Colorectal cancer (CRC) incidence in patients younger than 50 years of age, commonly defined as early-onset (EO-CRC), is rising. EO-CRC often presents with distinct clinicopathologic features. However, data on prognosis are conflicting and outcomes with modern treatment approaches for metastatic disease are still limited.

MATERIALS AND METHODS

We prospectively enrolled patients with metastatic CRC (mCRC) to a biobanking and clinical data collection protocol from 2014 to 2018. We grouped the cohort based on age at initial diagnosis: < 40 years, 40-49 years, and ≥ 50 years. We used regression models to examine associations among age at initial diagnosis, treatments, clinicopathologic features, and survival.

RESULTS

We identified 466 patients with mCRC (45 [10%] age < 40 years, 109 [23%] age 40-49 years, and 312 [67%] age ≥ 50 years). Patients < 40 years of age were more likely to have received multiple metastatic resections (odds ratio [OR], 3.533; P = .0066) than their older counterparts. Patients with EO-CRC were more likely to receive triplet therapy than patients > 50 years of age (age < 40 years: OR, 6.738; P = .0002; age 40-49 years: OR, 2.949; P = .0166). Patients 40-49 years of age were more likely to have received anti-EGFR therapy (OR, 2.633; P = .0016). Despite differences in care patterns, age did not predict overall survival.

CONCLUSION

Despite patients with EO-CRC receiving more intensive treatments, survival was similar to the older counterpart. However, EO-CRC had clinical and molecular features associated with worse prognoses. Improved biologic understanding is needed to optimize clinical management of EO-CRC. The cost-benefit ratio of exposing patients with EO-CRC to more intensive treatments has to be carefully evaluated.

Changes in patient-reported outcomes (PROs) and tumor markers (TMs) to predict treatment response and survival outcomes in patients with metastatic gastrointestinal (GI) cancer

6560

Background: PROs assessing quality of life (QOL) and symptoms at a single timepoint frequently correlate with clinical outcomes in patients with cancer, yet efforts to understand how longitudinal changes in PROs can predict for treatment outcomes are lacking. In practice, oncologists often use changes in serum TMs (CEA and CA19-9) to monitor patients with GI cancer, and thus we sought to examine associations of 1-month changes in PROs and TMs with treatment response and survival outcomes among patients with advanced GI cancer. Methods: We prospectively enrolled patients with metastatic GI cancer prior to initiating chemotherapy at Massachusetts General Hospital from 5/2019-12/2020. At baseline (start of treatment) and 1-month later, we collected PROs (QOL [Functional Assessment of Cancer Therapy General {FACT-G}], physical symptoms [Edmonton Symptom Assessment System {ESAS}], and psychological symptoms [Patient Health Questionnaire-4 {PHQ-4}]) and TMs. We used regression models to examine associations of 1-month changes in PROs and TMs with treatment response (clinical benefit [defined as decreased or stable tumor burden] or progressive disease at the time of first scan) and survival outcomes (progression-free survival [PFS] and overall survival [OS]), adjusted for baseline values of each respective variable. Results: We enrolled 159 of 191 patients approached (83.2% enrollment); 134 had 1-month follow-up data (median age = 64 years [range: 28 to 84 years], 64.2% male, 46.3% pancreaticobiliary cancer). For treatment response, 63.4% had clinical benefit and 36.6% had progressive disease at the time of first scan (mean time to first scan = 2.01 months). Changes in PROs (ESAS-Total: OR = 0.97, p = 0.022; ESAS-Physical: OR = 0.96, p = 0.027; PHQ-4 depression: OR = 0.67, p = 0.014; FACT-G: OR = 1.07, p = 0.001), but not TMs (CEA: OR = 1.00, p = 0.836 and CA19-9: OR = 1.00, p = 0.796), were associated with clinical benefit at the time of first scan. Changes in ESAS-Total (HR = 1.03, p = 0.004), ESAS-Physical (HR = 1.03, p = 0.021), PHQ-4 depression (HR = 1.22, p = 0.042), FACT-G (HR = 0.97, p = 0.003), and CEA (HR = 1.00, p = 0.001) were predictors of PFS. Changes in ESAS-Total (HR = 1.03, p = 0.006) and ESAS-Physical (HR = 1.04, p = 0.015) were predictors of OS, but 1-month changes in TMs (CEA: HR = 1.00, p = 0.377 and CA19-9: HR = 1.00, p = 0.367) did not significantly predict for OS. Conclusions: We found that 1-month changes in PROs can predict for treatment response and survival outcomes in patients with advanced GI cancers. Notably, 1-month changes in CEA only correlated with PFS, while changes in CA19-9 did not significantly predict treatment response or survival outcomes. These findings highlight the potential for early changes in PROs to predict treatment outcomes while underscoring the need to monitor and address PROs in patients with advanced cancer.

Clinical and mutational profile of ARID1A-mutated gastrointestinal cancers: Duration of response to platinum-based chemotherapy

e15611

Background: ARID1A is mutated in several cancer types, with studies reporting mutations in up to 10% of colorectal cancers (CRC) and as high as 35% of gastric and pancreatic cancers. The ARID1A gene encodes a member of the SWI/SNF (SWItch/Sucrose Non-Fermentable) chromatin remodeling complex and functions as a tumor suppressor. ARID1A has also been implicated in double-stranded DNA repair via both homologous recombination and non-homologous end-joining, potentially conferring platinum sensitivity. We sought to characterize this subset of gastrointestinal (GI) malignancies. Methods: We identified patients with locally advanced or metastatic ARID1A-mutated GI malignancies treated at Massachusetts General Hospital (MGH) by next-generation sequencing. Patients were selected who gave consent to molecular testing and who were enrolled on to a study. We evaluated clinical characteristics and outcomes for patients undergoing treatment at MGH between 2009 and May 2020. The Kaplan-Meier method was used to calculate progression free survival (PFS) to first-line platinum-based chemotherapy. Results: We captured 38 patients with ARID1A-mutated tumors. Median age at diagnosis was 66 (range 31-87) and 63.2% of patients were male (n = 24). Tumor types varied, including CRC (n = 13, 34.2%), esophagogastric (n = 13, 34.2%), pancreatic (n = 6, 15.7%), cholangiocarcinoma (n = 2, 5.3%), small bowel (n = 1, 2.6%), anal (n = 1, 2.6%), and unknown GI primary (n = 2, 5.3%). Most were metastatic at diagnosis (n = 23, 60.5%). The identified ARID1A mutations were each distinct, occurring along the length of the gene and were comprised of missense (n = 10, 26.3%), nonsense (n = 12, 31.6%), frameshift (n = 13, 34.2%), and splice-site (n = 3, 7.9%) mutations. We observed on average 4-5 co-mutations per tumor, with TP53 (n = 25, 65.8%), KRAS (n = 14, 36.8%), APC (n = 11, 28.9%), BRCA2 (n = 7, 18.4%) and BRAF (n = 7, 18.4%) occurring most frequently. Tumors were both microsatellite stable (n = 23, 60%) and microsatellite unstable (n = 7, 18.4%). Most patients (n = 37, 97.4%) received a platinum-based chemotherapy as first-line therapy including FOLFOX (n = 23, 60.5%), FOLFIRINOX (n = 10, 26.3%), gemcitabine/cisplatin (n = 2, 5.3%), carboplatin/5-FU (n = 1, 2.6%), and carboplatin/etoposide (n = 1, 2.6%). Median PFS for first-line platinum based chemotherapy was 14.0 months (CI 8.2-34.7) overall. For patients with CRC, PFS to platinum-based therapy was 14.0 months (CI 4.8-not reached) compared with 9.6 months for non-CRC (CI 7.4-not reached). Conclusions: To our knowledge, this is the first assessment of clinical characteristics and outcomes for ARID1A-mutated GI malignancies. Mutations in ARID1A are highly diverse, without a clear association with tumor type. Future studies assessing response to platinum-based chemotherapy are warranted.

Local and systemic recurrence following total neoadjuvant therapy (TNT) and resection for borderline resectable and locally advanced pancreatic adenocarcinoma: Long-term follow up from two phase II studies

4133

Background: With the advent of FOLFIRINOX, the management of pancreatic cancer has undergone a profound change. There has been a shift to TNT with FOLFIRINOX followed by radiation and an attempt at surgical resection. Recent trials of TNT have demonstrated an ability to resect locally advanced (LA) and borderline resectable disease. There is a lack of prospective data demonstrating local and systemic recurrence rates after TNT. Methods: Two previously reported prospective clinical trials (Murphy JE, et al, JAMA Oncol 2018, 2019) of total neoadjuvant therapy were conducted between 2012 and 2018 for borderline and LA disease (NCT01591733, NCT01821729). Patients received FOLFIRINOX for 8 cycles. Upon restaging, patients with resolution of vascular involvement received short-course chemoradiotherapy (5 Gy x 5 with protons or 3 Gy x 10 w photons) with capecitabine (N=34). Patients with persistent vascular involvement received long-course chemoradiotherapy with capecitabine (N=56). All patients were considered for resection after TNT except for those patients with metastatic or unresectable disease. Results: 97 eligible patients were enrolled and started treatment on the borderline resectable (n = 48) and locally advanced (n= 49) study. 90 patients completed therapy. 80 patients were taken to the operating room. 61 patients had R0 resection and 5 patients had R1 resection. The table shows the distribution of local recurrences, local recurrences and metastatic disease, and metastatic disease alone. With a median follow-up of 5.2 years (range: 2.4-6.0), of the 61 R0 patients, 22 patients remained alive and free of disease, 7 patients had a local recurrence, 4 patients had locoregional and metastatic recurrence, and 24 patients had a metastatic recurrence. 3 patients who underwent R0 resection died of unrelated causes. Median survival for patients undergoing R0 resection is 43.8 months. Conclusions: Total neoadjuvant therapy for locally advanced and borderline resectable pancreatic cancer is potentially curable and may change the pattern of spread.[Table: see text]

Supportive oncology care at home intervention for patients with pancreatic cancer

6558

Background: Patients with pancreatic cancer receiving chemotherapy often experience substantial symptoms and high healthcare utilization. We sought to determine the feasibility of delivering a Supportive Oncology Care at Home intervention designed to address the needs of patients receiving treatment for pancreatic cancer. Methods: We prospectively enrolled patients with pancreatic cancer who were participating in a parent trial of neoadjuvant FOLFIRINOX and residing in-state, within 50 miles of our hospital. Patients received the Supportive Oncology Care at Home intervention during neoadjuvant treatment (i.e., up to 4 months). The intervention entailed: 1) remote monitoring of daily patient-reported symptoms, daily vital signs, and weekly body weight; 2) a hospital in the home care model for symptom assessment and management; and 3) structured communication with the oncology team. We defined the intervention as feasible if ≥60% of patients enrolled in the study and ≥60% completed the daily assessments within the first two weeks of enrollment. We tracked numbers of phone calls, emails, and home visits generated by the intervention. We conducted exit interviews with patients, caregivers, and oncology clinicians to assess the acceptability of the intervention. In addition, we compared rates of treatment delays, urgent clinic visits, emergency room (ER) visits, and hospitalizations among those who did (n = 20) and did not (n = 24) receive Supportive Oncology Care at Home from the parent trial. Results: From 1/2019-9/2020, we enrolled 80.8% (21/26) of potentially eligible patients. One patient became ineligible following consent due to moving out-of-state, resulting in 20 participants (median age = 67 years [range 55-77]; 60.0% female). Within the first two weeks of enrollment, 65.0% completed all the daily assessments, with participants reporting 96.1% of daily symptoms, 96.1% of daily vital signs, and 92.5% of weekly body weights. Each participant generated an average of 2.22 phone calls (range 0.62-3.77), 2.96 emails (range 1.50-5.88), and 0.15 home visits (range 0-0.69) per week. During exit interviews, > 80% of patients, caregivers, and clinicians found the intervention to be helpful and convenient, and they reported high satisfaction with the communication among patients, clinicians, and the hospital in the home team. Patients receiving the intervention had lower rates of treatment delays (55.0% v 75.0%), urgent clinic visits (10.0% v 25.0%), ER visits or hospitalizations (45.0% v 62.5%), as well as a lower proportion of days spent in urgent clinic, ER, or hospital (2.7% v 7.8%), compared with those not receiving the intervention who were in the same parent trial. Conclusions: These findings demonstrate the feasibility and acceptability of a Supportive Oncology Care at Home intervention. Future work will investigate the efficacy of this intervention for decreasing healthcare use and improving patient outcomes. Clinical trial information: NCT03798769.

Minimal Residual Disease Detection using a Plasma-only Circulating Tumor DNA Assay in Patients with Colorectal Cancer

PURPOSE

Detection of persistent circulating tumor DNA (ctDNA) after curative-intent surgery can identify patients with minimal residual disease (MRD) who will ultimately recur. Most ctDNA MRD assays require tumor sequencing to identify tumor-derived mutations to facilitate ctDNA detection, requiring tumor and blood. We evaluated a plasma-only ctDNA assay integrating genomic and epigenomic cancer signatures to enable tumor-uninformed MRD detection.

EXPERIMENTAL DESIGN

A total of 252 prospective serial plasma specimens from 103 patients with colorectal cancer undergoing curative-intent surgery were analyzed and correlated with recurrence.

RESULTS

Of 103 patients, 84 [stage I (9.5%), II (23.8%), III (47.6%), IV (19%)] had evaluable plasma drawn after completion of definitive therapy, defined as surgery only (n = 39) or completion of adjuvant therapy (n = 45). In "landmark" plasma drawn 1-month (median, 31.5 days) after definitive therapy and >1 year follow-up, 15 patients had detectable ctDNA, and all 15 recurred [positive predictive value (PPV), 100%; HR, 11.28 (P < 0.0001)]. Of 49 patients without detectable ctDNA at the landmark timepoint, 12 (24.5%) recurred. Landmark recurrence sensitivity and specificity were 55.6% and 100%. Incorporating serial longitudinal and surveillance (drawn within 4 months of recurrence) samples, sensitivity improved to 69% and 91%. Integrating epigenomic signatures increased sensitivity by 25%-36% versus genomic alterations alone. Notably, standard serum carcinoembryonic antigen levels did not predict recurrence [HR, 1.84 (P = 0.18); PPV = 53.9%].

CONCLUSIONS

Plasma-only MRD detection demonstrated favorable sensitivity and specificity for recurrence, comparable with tumor-informed approaches. Integrating analysis of epigenomic and genomic alterations enhanced sensitivity. These findings support the potential clinical utility of plasma-only ctDNA MRD detection.

Severe lymphopenia predicts poorer survival in patients with rectal cancer undergoing neoadjuvant chemoradiation

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Background: Chemoradiation (CRT) induced lymphopenia is common and associated with poorer survival in multiple solid malignancies. The objective of this study was to evaluate the prognostic impact of lymphopenia in patients with rectal cancer undergoing neoadjuvant CRT. We hypothesized that severe lymphopenia would correlate with worse survival. Methods: The inclusion criteria for this single-institution retrospective study were: 1) biopsy-proven diagnosis of rectal adenocarcinoma, 2) receipt of neoadjuvant CRT followed by surgery, and 3) absolute lymphocyte count (ALC) available prior to and within 12 weeks of CRT. In general, CRT consisted of 5-fluorouracil or capecitabine and RT with 50.4 Gy over 28 fractions. Lymphopenia was graded according to CTCAE v5.0. The primary variable of interest was ALC nadir within 12 weeks of CRT, dichotomized by ALC of < 0.5 k/μl (Grade 3 lymphopenia). The primary endpoint was overall survival (OS). Cox modeling and Kaplan-Meier methods were used to perform survival analyses. Results: 193 patients were identified. Median follow-up for the entire cohort was 68 months. Median age was 58. 62% were male, 82% were Caucasian, and 90% had ECOG ≤1. Median tumor distance from anal verge was 8 cm. Overall clinical stage was 1 or 2 in 23% and 3 in 77%. Median baseline CEA was 3.2 ng/ml. 83% received chemotherapy following RT. Following CRT, 70% underwent low anterior resection and 30% underwent abdominoperineal resection. Median baseline ALC for the entire cohort was 1.7 k/ul. ALC nadir within 12 weeks of initiating CRT was < 0.5 k/ul among 110 (57%) patients. Patients who developed severe lymphopenia with CRT had a lower baseline hemoglobin (median 13.3 vs. 14.0 g/dl, p = 0.022) and lower baseline ALC (median 1.6 vs. 1.8 k/ul, p = 0.010) compared to those who did not develop severe lymphopenia. There were no differences in disease and treatment characteristics between the two groups. On multivariable Cox model, severe lymphopenia was significantly associated with increased hazards of death (HR = 3.52 [95% CI 1.47-8.44], p = 0.005). Receipt of chemotherapy post-CRT (HR = 0.22 [95% CI 0.09-0.54], p = 0.001) predicted better OS while higher pathologic T (HR = 8.01 [95% CI 2.98-17.21], p < 0.001) and N stage (HR = 9.43 [95% CI 3.19-27.86], p < 0.001) and positive surgical margin (HR = 3.77 [95% CI 1.13-12.62], p = 0.031) predicted worse OS. The 5-year OS was 79% vs. 92% in the cohort with vs. without severe lymphopenia, respectively (log-rank p = 0.001). Conclusions: CRT-induced lymphopenia is common and severe lymphopenia may be a prognostic marker of poorer survival in rectal cancer. Closer observation in high-risk patients and treatment modifications may be potential approaches to mitigating CRT-induced lymphopenia. Our findings also suggest an important role of the host immunity in rectal cancer outcomes, supporting the ongoing efforts of immunotherapy trials in rectal cancer.

Prognostic impact of chemoradiation-related lymphopenia in patients with gastric and gastroesophageal cancer

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Background: Limited data exists on how chemoradiation (CRT)-induced lymphopenia affects survival outcomes in patients with gastric and gastroesophageal junction (GEJ) cancer. We evaluated the association between severe lymphopenia and its association with survival in gastric and GEJ cancer patients treated with CRT. We hypothesized that severe lymphopenia would be a poor prognostic factor. Methods: We performed a retrospective analysis of 154 patients with stage 1-3 gastric or GEJ cancer who underwent CRT at our institution. Patients underwent photon-based radiation therapy (RT) with a median dose of 50.4 Gy (IQR 45.0-50.4 Gy) over 28 fractions and concurrent chemotherapy (CTX) with carboplatin/paclitaxel, 5-fluorouracil based regimen, or capecitabine. 49% received CTX prior to RT. 84% underwent surgical resection, 57% pre-CRT and 26% post-CRT. Absolute lymphocyte count (ALC) at baseline and at 2 months since initiating RT were analyzed. Severe lymphopenia, defined as Grade 3 or worse lymphopenia (ALC < 0.5 k/μl), was analyzed for any association with overall survival (OS). Results: Median time of follow up was 48 months. Median age was 65. 77% were male and 86% were Caucasian. ECOG PS was 0 or 1 in 90% and 2 in 10%. Tumor location was stomach in 38% and GEJ in 62%. Timing of CRT was preoperative among 68% and postoperative among 32%. The median ALC at baseline for the entire cohort was 1.6 k/ul (range 0.3-7.0 k/ul). At 2 months post-CRT, 49 (32%) patients had severe lymphopenia. Patients with severe lymphopenia post-CRT had a slightly lower baseline TLC compared to patients without severe lymphopenia (median TLC 1.4 k/ul vs. 1.6 k/ul; p = 0.005). There were no differences in disease and treatment characteristics between the two groups. On the multivariable Cox model, severe lymphopenia post-CRT was significantly associated with increased risk of death (HR = 3.99 [95% CI 1.55-10.28], p = 0.004). ECOG PS 2 (HR = 34.97 [95% CI 2.08-587.73], p = 0.014) and postoperative CRT (HR = 5.55 [95% CI 1.29-23.86], p = 0.021) also predicted worse OS. The 4-year OS among patients with severe lymphopenia was 41% vs. 61% among patients with vs. without severe lymphopenia (log-rank test p = 0.041). Conclusions: Severe lymphopenia significantly correlated with poorer OS in patients with gastric or GEJ cancer treated with CRT. CRT-induced lymphopenia may be an important prognostic factor for survival in this patient population. Closer observation in high-risk patients and treatment modifications may be potential approaches to mitigating CRT-induced lymphopenia.

Prognostic impact of chemoradiation-related lymphopenia in patients with locally advanced pancreatic cancer

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Background: Chemoradiation (CRT) induced lymphopenia is common and associated with poorer survival in multiple solid malignancies. The objective of this study was to evaluate the prognostic impact of lymphopenia in patients with nonmetastatic, unresectable pancreatic ductal adenocarcinoma (PDAC) treated by neoadjuvant FOLFIRINOX (5-fluorouracil [5FU]/leucovorin/irinotecan/oxaliplatin) followed by CRT. We hypothesized that severe lymphopenia would correlate with worse survival. Methods: The inclusion criteria for this single-institution retrospective study were: 1) biopsy-proven diagnosis of unresectable PDAC, 2) absence of distant metastasis, 3) receipt of neoadjuvant FOLFIRINOX followed by CRT, and 4) absolute lymphocyte count (ALC) available prior to and two months after initiating CRT. In general, CRT consisted of 5FU or capecitabine and RT with 58.8 Gy over 28 fractions. Lymphopenia was graded according to CTCAE v5.0. The primary variable of interest was lymphopenia at two months, dichotomized by ALC of < 0.5/μl (Grade 3 lymphopenia). The primary endpoint was overall survival (OS). Cox modeling and Kaplan-Meier methods were used to perform survival analyses. Results: A total of 138 patients were identified. Median follow-up for the entire cohort was 16 months. Median age was 65. Fifty-six percent were female, 86% were Caucasian, and 97% had ECOG ≤1. Median tumor size was 3.8 cm. Tumor location was pancreatic head in 63%, body in 22%, tail in 8%, and neck in 7%. Median baseline ALC for the entire cohort was 1.5 k/ul. Two months after initiating CRT, 106 (77%) had severe (Grade 3 or worse) lymphopenia. While there were no significant differences in baseline patient or disease characteristics, patients with severe lymphopenia received higher doses of RT with longer duration of treatment compared to those without severe lymphopenia. On multivariable Cox model, severe lymphopenia at two months was significantly associated with increased hazards of death (HR = 4.00 [95% CI 2.03-7.89], p < 0.001). Greater number of neoadjuvant FOLFIRINOX cycles received prior to CRT was associated with lower hazards of death (HR = 0.84 [95% CI 0.77-0.92], p < 0.001). The 12-month OS was 73% vs. 90% in the cohort with vs. without severe lymphopenia, respectively (log-rank p < 0.001). Conclusions: Treatment-related lymphopenia is common and severe lymphopenia may be a prognostic marker of poorer survival in locally advanced pancreatic cancer. Closer observation in high-risk patients and minimization of RT dose and duration are potential approaches to mitigating CRT-related lymphopenia. Our findings also suggest an important role of the host immunity in pancreatic cancer outcomes, supporting the ongoing efforts of immunotherapy trials in pancreatic cancer.

Associations of baseline patient-reported outcomes with treatment outcomes in advanced gastrointestinal cancer

BACKGROUND

Patient-reported outcomes (PROs) assessing quality of life (QOL) and symptom burden correlate with clinical outcomes in patients with cancer. However, to the authors' knowledge, data regarding associations between PROs and treatment response are lacking.

METHODS

The authors prospectively approached consecutive patients with advanced gastrointestinal cancer who were initiating a new treatment. Prior to treatment, patients reported their QOL (Functional Assessment of Cancer Therapy-General [FACT-G], 4 subscales: Functional, Physical, Emotional, Social; higher scores indicate better QOL) and symptom burden (Edmonton Symptom Assessment System [ESAS], Patient Health Questionnaire-4 [PHQ-4]; higher scores represent greater symptoms). Regression models were used to examine associations of baseline PROs with treatment response (clinical benefit or progressive disease [PD] at time of first scan), healthcare utilization, and survival.

RESULTS

From May 2019 to April 2020, a total of 112 patients with advanced gastrointestinal cancer were enrolled. For treatment response, 64.3% had CB and 35.7% had PD. Higher baseline ESAS-Physical (odds ratio, 1.04; P = .027) and lower FACT-G Functional (odds ratio, 0.92; P = .038) scores were associated with PD. Higher ESAS-Physical (hazard ratio [HR], 1.03; P = .044) and lower FACT-G Total (HR, 0.96; P = .005), FACT-G Physical (HR, 0.89; P < .001), and FACT-G Functional (HR, 0.87; P < .001) scores were associated with a greater hospitalization risk. Lower FACT-G Total (HR, 0.96; P = .009) and FACT-G Emotional (HR, 0.86; P = .012) scores as well as higher ESAS-Total (HR, 1.03; P = .014) and ESAS-Physical (HR, 1.04; P = .032) scores were associated with worse survival.

CONCLUSIONS

Baseline PROs are associated with treatment response in patients with advanced gastrointestinal cancer, namely physical symptoms and functional QOL, in addition to health care use and survival. The findings of the current study support the association between PROs and important clinical outcomes, including the novel finding of treatment response.

Use of patient-reported outcomes (PROs) to predict treatment outcomes in patients with advanced cancer

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Background: PROs assessing quality of life (QOL) and physical symptoms often correlate with clinical outcomes in patients (pts) with cancer. Yet, data are lacking about the use of PROs to predict treatment response. We evaluated associations of baseline PROs with treatment response, healthcare use, and survival among pts with advanced gastrointestinal cancer. Methods: We prospectively enrolled pts with metastatic gastrointestinal cancer prior to initiating chemotherapy at Massachusetts General Hospital. At baseline (start of treatment), pts reported their QOL (Functional Assessment of Cancer Therapy General [FACT-G], subscales assess QOL across 4 domains: functional, physical, emotional, social well-being) and symptom burden (Edmonton Symptom Assessment System [ESAS]). Higher scores on FACT-G indicate better QOL, while higher scores on ESAS represent a greater symptom burden. We used regression models to examine associations of baseline PRO scores with treatment response (clinical benefit [CB] or progressive disease [PD] at the time of first scan based on clinical documentation), healthcare use (unplanned hospital admissions), and survival. Results: From 5/2019-3/2020, we enrolled 112 of 131 (85.5% enrollment) consecutive pts (median age = 62.8, 61.6% male, 45.5% pancreatobiliary cancer). For treatment response, 64.3% had CB and 35.7% had PD. Higher ESAS-physical (B = 1.04, p = .027) and lower FACT-G functional (B = 0.92, p = .038) scores at baseline were significant predictors of PD. On the specific ESAS items, pts who experienced PD were more likely to report moderate/severe poor well-being (57.9% vs 29.7%; p = .001), pain (44.7% vs 25.0%; p < .050), drowsiness (42.1% vs 20.3%; p = .024), and diarrhea (23.7% vs 4.7%; p = .008) at baseline. Lower FACT-G total (HR = 0.96, p = .003), FACT-G physical (HR = 0.89, p < .001), FACT-G functional (HR = 0.87, p < .001), and higher ESAS-physical (HR = 1.03, p = .028) scores at baseline were significantly associated with greater risk of hospital admission. Lower FACT-G total (HR = 0.96, p = .009), FACT-G emotional (HR = 0.87, p = .014), as well as higher ESAS-total (HR = 1.03, p = .018) and ESAS-physical (HR = 1.03, p = .040) scores at baseline were significantly associated with greater risk of death. Conclusions: We found that baseline PROs predict treatment response in pts with advanced cancer, namely physical symptoms and functional QOL, in addition to healthcare use and survival outcomes. These findings further support the use of PROs to predict important clinical outcomes, including the novel finding of treatment response.

Chemoradiation-Related Lymphopenia and Its Association with Survival in Patients with Squamous Cell Carcinoma of the Anal Canal

BACKGROUND

Although treatment-related lymphopenia (TRL) is common and associated with poorer survival in multiple solid malignancies, few data exist for anal cancer. We evaluated TRL and its association with survival in patients with anal cancer treated with chemoradiation (CRT).

MATERIALS AND METHODS

A retrospective analysis of 140 patients with nonmetastatic anal squamous cell carcinoma (SCC) treated with definitive CRT was performed. Total lymphocyte counts (TLC) at baseline and monthly intervals up to 12 months after initiating CRT were analyzed. Multivariable Cox regression analysis was performed to evaluate the association between overall survival (OS) and TRL, dichotomized by grade (G)4 TRL (<0.2k/μL) 2 months after initiating CRT. Kaplan-Meier and log-rank tests were used to compare OS between patients with versus without G4 TRL.

RESULTS

Median time of follow-up was 55 months. Prior to CRT, 95% of patients had a normal TLC (>1k/μL). Two months after initiating CRT, there was a median of 71% reduction in TLC from baseline and 84% of patients had TRL: 11% G1, 31% G2, 34% G3, and 8% G4. On multivariable Cox model, G4 TRL at two months was associated with a 3.7-fold increased risk of death. On log-rank test, the 5-year OS rate was 32% in the cohort with G4 TRL versus 86% in the cohort without G4 TRL.

CONCLUSION

TRL is common and may be another prognostic marker of OS in anal cancer patients treated with CRT. The association between TRL and OS suggests an important role of the host immunity in anal cancer outcomes.

IMPLICATIONS FOR PRACTICE

This is the first detailed report demonstrating that standard chemoradiation (CRT) commonly results in treatment-related lymphopenia (TRL), which may be associated with a poorer overall survival (OS) in patients with anal squamous cell carcinoma. The association between TRL and worse OS observed in this study supports the importance of host immunity in survival among patients with anal cancer. These findings encourage larger, prospective studies to further investigate TRL, its predictors, and its relationship with survival outcomes. Furthermore, the results of this study support ongoing efforts of clinical trials to investigate the potential role of immunotherapy in anal cancer.

Patterns of Failure and the Need for Biliary Intervention in Resected Biliary Tract Cancers After Chemoradiation

BACKGROUND

This study assessed patterns of failure and rates of subsequent biliary intervention among patients with resected biliary tract cancers (BTCs) including gallbladder carcinoma (GBC) and extra- and intrahepatic cholangiocarcinoma (eCCA and iCCA) treated with adjuvant chemoradiation therapy (CRT).

METHODS

In this single-institution retrospective analysis of 80 patients who had GBC (n = 29), eCCA (n = 43), or iCCA (n = 8) treated with curative-intent resection and adjuvant CRT from 2007 to 2017, the median radiation dose was 50.4 Gy (range 36-65 Gy) with concurrent 5-fluorouracil (5-FU) chemotherapy. All but two of the patients received adjuvant chemotherapy. The 2-year locoregional failure (LRF), 2-year recurrence-free survival (RFS), and 2-year overall survival (OS), and univariate predictors of LRF, RFS, and OS were calculated for the entire cohort and for a subgroup excluding patients with iCCA (n = 72). The predictors of biliary interventions also were assessed.

RESULTS

Of the 80 patients (median follow-up period, 30.5 months; median OS, 33.9 months), 54.4% had American Joint Committee on Cancer (AJCC) stage 1 or 2 disease, 57.1% were lymph node-positive, and 66.3% underwent margin-negative resection. For the entire cohort, 2-year LRF was 23.8%, 2-year RFS was  43.7%, and 2-year OS was 62.1%.  When patients with iCCA were excluded, the 2-year LRF was 22.6%, the 2-year RFS was 43.9%, and the 2-year OS was 59.2%. In the overall and subgroup univariate analyses, lymph node positivity was associated with greater LRF, whereas resection margin was not. Biliary intervention was required for 12 (63.2%) of the 19 patients with LRF versus 11 (18%) of the 61 patients without LRF (P < 0.001). Of the 12 patients with LRF who required biliary intervention, 4 died of biliary complications.

CONCLUSIONS

The LRF rates remained significant despite adjuvant CRT. Lymph node positivity may be associated with increased risk of LRF. Positive margins were not associated with greater LRF, suggesting that CRT may mitigate LRF risk for this group. An association between LRF and higher rates of subsequent biliary interventions was observed, which may yield significant morbidity. Novel strategies to decrease the rates of LRF should be considered.

Impact of adjuvant therapy in patients with invasive intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

There is limited data on the efficacy of adjuvant therapy (AT) in patients with invasive intraductal papillary mucinous neoplasms of the pancreas (IPMN). This single center retrospective cohort study aims to assess the impact of AT on survival in these patients.

METHODS

Patients undergoing surgery for invasive IPMN between 1993 and 2018 were included in the study. We compared the clinicopathologic features and evaluated overall survival (OS) using multivariate Cox regression adjusting for adjuvant therapy, age, T and N stage, perineural and lymphovascular invasion. We also assessed survival differences between surgery alone and AT in node negative (N0) and node positive (N+) subgroups.

RESULTS

103 patients were included in the study; 69 underwent surgery alone while 34 also received AT. Patients in the AT group were significantly younger, presented at higher T and N stages and had more perineural and lymphovascular invasion. Median OS in the surgery alone group was 134 months and 65 months in the AT group, p = 0.052. On multivariate analysis, AT was not associated with improved OS; hazard ratio (HR) = 1.03 (0.52-2.05). In N0 patients, compared to surgery alone, AT was associated with a worse median OS (65 vs 167 months, p = 0.03), whereas in N+ patients there was a non-significant improvement (50.5 vs 20.4 months, p = 0.315).

CONCLUSION

AT did not improve survival in the overall cohort even after multivariate analysis. N0 patients have excellent survival, and AT should probably be avoided in them, whereas it may be considered in patients with N+ disease.

Serial ctDNA Monitoring to Predict Response to Systemic Therapy in Metastatic Gastrointestinal Cancers

PURPOSE

ctDNA offers a promising, noninvasive approach to monitor therapeutic efficacy in real-time. We explored whether the quantitative percent change in ctDNA early after therapy initiation can predict treatment response and progression-free survival (PFS) in patients with metastatic gastrointestinal cancer.

EXPERIMENTAL DESIGN

A total of 138 patients with metastatic gastrointestinal cancers and tumor profiling by next-generation sequencing had serial blood draws pretreatment and at scheduled intervals during therapy. ctDNA was assessed using individualized droplet digital PCR measuring the mutant allele fraction in plasma of mutations identified in tumor biopsies. ctDNA changes were correlated with tumor markers and radiographic response.

RESULTS

A total of 138 patients enrolled. A total of 101 patients were evaluable for ctDNA and 68 for tumor markers at 4 weeks. Percent change of ctDNA by 4 weeks predicted partial response (PR, P < 0.0001) and clinical benefit [CB: PR and stable disease (SD), P < 0.0001]. ctDNA decreased by 98% (median) and >30% for all PR patients. ctDNA change at 8 weeks, but not 2 weeks, also predicted CB (P < 0.0001). Four-week change in tumor markers also predicted response (P = 0.0026) and CB (P = 0.022). However, at a clinically relevant specificity threshold of 90%, 4-week ctDNA change more effectively predicted CB versus tumor markers, with a sensitivity of 60% versus 24%, respectively (P = 0.0109). Patients whose 4-week ctDNA decreased beyond this threshold (≥30% decrease) had a median PFS of 175 days versus 59.5 days (HR, 3.29; 95% CI, 1.55-7.00; P < 0.0001).

CONCLUSIONS

Serial ctDNA monitoring may provide early indication of response to systemic therapy in patients with metastatic gastrointestinal cancer prior to radiographic assessments and may outperform standard tumor markers, warranting further evaluation.

Total Neoadjuvant Therapy With FOLFIRINOX in Combination With Losartan Followed by Chemoradiotherapy for Locally Advanced Pancreatic Cancer: A Phase 2 Clinical Trial

Importance

Patients with locally advanced pancreatic cancer have historically poor outcomes. Evaluation of a total neoadjuvant approach is warranted.

Objective

To evaluate the margin-negative (R0) resection rate of neoadjuvant FOLFIRINOX (fluorouracil, leucovorin, oxaliplatin, and irinotecan) and losartan followed by chemoradiotherapy for locally advanced pancreatic cancer.

Design, Setting, and Participants

A single-arm phase 2 clinical trial was conducted at a large academic hospital from August 22, 2013, to May 22, 2018, among 49 patients with previously untreated locally advanced unresectable pancreatic cancer as determined by multidisciplinary review. Patients had Eastern Cooperative Oncology Group performance status 0 or 1 and adequate hematologic, renal, and hepatic function. Median follow-up for the analysis was 17.1 months (range, 5.0-53.7) among 27 patients still alive at study completion.

Interventions

Patients received FOLFIRINOX and losartan for 8 cycles. Patients with radiographically resectable tumor after chemotherapy received short-course chemoradiotherapy (5 GyE × 5 with protons) with capecitabine. Patients with persistent vascular involvement received long-course chemoradiotherapy (50.4 Gy with a vascular boost to 58.8 Gy) with fluorouracil or capecitabine.

Main Outcomes and Measures

R0 resection rate.

Results

Of the 49 patients (26 women and 23 men; median age 63 years [range, 42-78 years]), 39 completed 8 cycles of FOLFIRINOX and losartan; 10 patients had fewer than 8 cycles due to progression (5 patients), losartan intolerance (3 patients), and toxicity (2 patients). Seven patients (16%) had short-course chemoradiotherapy while 38 (84%) had long-course chemoradiotherapy. Forty-two (86%) patients underwent attempted surgery, with R0 resection achieved in 34 of 49 patients (69%; 95% CI, 55%-82%). Overall median progression-free survival was 17.5 months (95% CI: 13.9-22.7) and median overall survival was 31.4 months (95% CI, 18.1-38.5). Among patients who underwent resection, median progression-free survival was 21.3 months (95% CI, 16.6-28.2), and median overall survival was 33.0 months (95% CI, 31.4 to not reached).

Conclusions and Relevance

Total neoadjuvant therapy with FOLFIRINOX, losartan, and chemoradiotherapy provides downstaging of locally advanced pancreatic ductal adenocarcinoma and is associated with an R0 resection rate of 61%.

Trial Registration

ClinicalTrials.gov identifier: NCT01821729.

Preliminary analysis of total neoadjuvant therapy for patients with locally advanced gastric (G) and gastroesophageal (GE) adenocarcinoma

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Background: Nearly half of patients with G/GE cancer do not receive or complete post-operative chemotherapy and/or chemoradiation (CRT). Total neoadjuvant therapy (TNT) is as an emerging alternate treatment strategy. We have previously reported a 28% pCR with FOLFIRINOX followed by CRT. However, TNT outcomes with FLOT or FOLFOX followed by CRT are lacking. Methods: We retrospectively analyzed patients after resection of locally advanced G/GE after receiving TNT. Patient received neoadjuvant FOLFOX or FLOT x 8 cycles, CRT (G 45 Gy, GE 50.4 Gy) with concurrent chemotherapy (5FU, carboplatin/paclitaxel). The primary aim was to explore TNT completion rates. Secondary aims included pCR and toxicity. We performed descriptive statistics, t-test, chi-squared, and Fisher’s exact tests as appropriate. Results: From 12/2015 to 8/2019, 57.1% (40/70) completed TNT and resection (15.7% active treatment, 15.7% progressive disease, 11% treated elsewhere). Median age was 66.0 (range:27-79) and 73% male. Tumor locations included 57.5% G, 30.0% GE, and 12.5% overlapping. Neoadjuvant chemotherapy included FLOT 22.5% (n = 9) or FOLFOX 77.5% (n = 31). Overall we found a 25% pCR without significant differences between type of neoadjuvant chemotherapy. Conclusions: TNT followed by resection is feasible with acceptable rates of treatment completion and toxicity. Notable limitations include the retrospective analysis, small sample size, and heterogenous treatment. The pCR rate is promising and warrants further prospective study to optimize TNT approaches. [Table: see text]

A pilot study of durvalumab/tremelimumab (durva/treme) and radiation (XRT) for metastatic biliary tract cancer (mBTC): Preliminary safety and efficacy

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Background: Metastatic biliary tract cancer (mBTC) is a lethal malignancy with median 5 year OS of less than 10%. Immunotherapy, particularly single agent anti-PD-1/PD-L1, has limited efficacy in mBTC with ORR~9-15%. Recently presented data shows responses in metastatic MSS pancreatic or colon cancer with combination anti-PD-1/CTLA-4 and radiation (XRT) to produce systemic response (abscopal effect) (Parikh A, GI ASCO 2019, ASCO 2019.). We evaluate safety and efficacy of dual PD-1/CTLA-4 inhibition with XRT in MSS mBTC. Methods: 15 of a planned 15 mBTC patients were enrolled. Eligible pts had histologically-confirmed mBTC, ECOG-PS 0/1, and must have progressed on at least one line of previous therapy or refused standard therapy. Safety cohort of 6 pts of durva 1500 mg/treme 75 mg q4w was enrolled. If > 2 DLTs, patients were enrolled subsequently to dose level -1 (durva 1125 mg/ treme 75 mg q4w). 3 fractions of 8 Gy of radiation at C2D1 every other day to a single metastatic site. Durva/treme continued for 4 cycles, followed by 4 cycles of maintenance durva until progressive disease, discontinuation or withdrawal. Endpoints include disease control rate (DCR (SD+PR+CR)), PFS and OS and safety. Radiological evaluations were done q2 mo. Results: 15 mBTC pts enrolled and evaluable from May 2018 to March 2019. Median age 63 years (range 48-75), 47% male. DLTs occurred in 3 patients during the safety run-in. One patient experienced DLT at dose level -1 and subsequent expansion. 3 patients did NOT reach radiation therapy. DCR was 27% with a 13% PR and 7% CR. Of those who reached radiation, DCR was 33% with a 17% PR and 8% CR. At time of analysis, median PFS was 54 days for ITT mBTC. Duration of response for 4 patients with DCR was 26, 52, 122, 254+ days. Treatment-related adverse events were reported in 12/15 patients (80%). Grade ≥3 toxicities were seen in 9/15 pts (60%) with lymphopenia (5 grade 3) and elevated LFTs (2 grade 4 and 4 grade 2) being the main adverse events. All patients with disease control were not MSI. Conclusions: Combination of durva/treme XRT is feasible and shows preliminary activity in metastatic BTC. An expansion cohort is being planned to confirm activity. Clinical trial information: NCT03482102.

Noninvasive comprehensive genomic profiling from plasma ctDNA in pancreatic cancer patients

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Background: The use of comprehensive genomic profiling (CGP) is increasing in pancreatic ductal adenocarcinoma (PDAC) as knowledge improves regarding molecular drivers of tumorigenesis and effective targeted therapies emerge. However, adequate tissue sampling is often limited. Plasma-based CGP offers a non-invasive approach to assess biomarkers that may impact treatment decisions. Methods: We retrospectively evaluated genomic and clinical data from 97 PDAC patients with circulating tumor DNA (ctDNA) testing from 9/2016-8/2019 (Guardant Health, Inc.). ctDNA analysis included single nucleotide variants (SNV), fusions, indels and copy number variations (CNV) of up to 74 genes. ctDNA results were assessed across clinical variables. We evaluated for actionable alterations. Results: A total of 114 samples were obtained from 97 patients for ctDNA testing. ctDNA alterations were detected in 82% (93/114) of all samples, including 90% (18/20) at diagnosis, 88% (59/67) at progression, and 56% (10/18) while on stable therapy. ctDNA alterations were found at each stage of PDAC: in 25% (1/4) of samples with resectable disease, 75% (3/4) with borderline resectable disease, 82% (9/11) with locally advanced disease, and 85% (81/95) with metastatic disease. One or more KRAS alterations were detected in 55% (51/93) of patients with alterations present. The median maximum mutant allele frequency was similar between the cohort of patients with KRAS detected (0.55%) versus not detected (0.70%). 8% (8/97) of patients had potentially actionable alterations (2 activating BRAF SNVs, 1 ERBB2 CNV, 1 ERBB2 activating SNV, 1 KRAS G12C, and 3 indels in Homologous Recombination Deficiency genes). Median turnaround time was 8 days. 51% (49/97) of patients had both plasma-based CGP and tissue-based CGP. Of these patients, tissue-based CGP showed ≥ 1 alterations detected in 82% (40/49), test failure in 14% (7/49), and no alterations detected in 4% (2/49). Conclusions: Plasma-based CGP detected ctDNA alterations in 90% of samples tested at diagnosis and 82% of all samples. Potentially actionable mutations were found in 8% of patients, with prompt processing time allowing for rapid decision making.

Chemoradiation-related lymphopenia and its association with survival in patients with anal cancer

3

Background: While treatment-related lymphopenia (TRL) is common and associated with poorer survival in multiple solid malignancies, little data exists for anal cancer. We evaluated TRL and its association with survival in anal cancer patients treated with chemoradiation (CRT). Methods: A retrospective analysis of 140 patients with non-metastatic anal squamous cell carcinoma (SCC) treated with definitive CRT was performed. Total lymphocyte counts (TLC) at baseline and monthly intervals up to 12 months after initiating CRT were analyzed. Multivariable Cox regression analysis was performed to evaluate the association between overall survival (OS) and TRL, dichotomized by G4 TRL ( < 0.2k/μl) two months after initiating CRT. Kaplan-Meier and log-rank tests were used to compare OS between patients with versus without G4 TRL. Results: Median time of follow-up was 55 months. Prior to CRT, 95% of patients had a normal TLC ( > 1k/μl). Two months after initiating CRT, there was a median of 71% reduction in TLC from baseline and 84% of patients had TRL: 11% G1, 31% G2, 34% G3, and 8% G4. On multivariable Cox model, G4 TRL at two months was associated with a 3.7-fold increased risk of death (p = 0.013). On log-rank test, the 5-year OS rate was shorter in the cohort with versus without G4 TRL at two months (32% vs. 86%, p < 0.001). Conclusions: TRL is common and may be another prognostic marker of OS in anal cancer patients treated with CRT. The association between TRL and OS supports the hypothesis that host immunity plays an important role in survival among patients with anal cancer. These results support ongoing efforts of randomized trials underway to evaluate the potential role of immunotherapy in localized anal cancer.

Phase II study of lamivudine in p53 mutant metastatic colorectal cancer (mCRC)

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Background: Non-coding repeat RNAs in cancers are pervasive and “mimic” viruses with activation of pattern recognition receptors and the innate immune response. Many repeat RNAs replicate in cancer genomes through a reverse transcriptional intermediate analogous to retroviruses. Nucleoside reverse transcriptase inhibitors (NRTIs) block this retroviral life cycle to increases repeat RNAs in p53 mutant colon cancer cell cancer lines. We initiated a Phase 2 study of lamivudine (3TC) in TP53 mutant mCRC. Methods: Two-stage design with target accrual of 20 patients (pts) in stage 1 and total of 32. Eligibility: pts with p53 mutant refractory mCRC with progression on or intolerance to 5FU, oxaliplatin and irinotecan and anti-EGFR if RAS WT. RNA sequencing was performed on pre-treatment (tx) and on tx biopsy to evaluate for repeat RNA expression and expression of other genes linked to 3TC response/resistance. Radiation was allowed. 9 pts were treated with 3TC 150 mg po bid for 28-day cycles, the maximum FDA approved dose of 3TC in HIV. Subsequent pts were treated at 600 mg po bid, previously tested in P1 trials. Tumor assessments were performed every 8 weeks until documented disease progression by RECIST 1.1 criteria or drug intolerance. Results: 29/32 pts have been treated. Median age: 60 yrs. (27-82) 18 males, 11 females. 2/ 9 (22%) pts on standard 3TC dosing had stable disease (SD) on single agent 3TC with a duration of tx of 169 and 167 days, respectively. Both pts had an initial drop in CEA upon initiation of 3TC. Of the next 20 pts on high dose 3TC, 19 were evaluable. 4 had SD, for 110, 159, 130 and 228+ days. 14 pts had tx-related adverse events (TRAE). 1 pt with a definite Grade 1 TRAE (fatigue). No pts with Grade ≥3 TRAEs. We obtained pre-tx fresh frozen biopsies on 24/29 pts. Of those with SD, 4 had biopsies and differential expression identified significantly higher HSATII repeat RNA in pts with SD compared to PD. There was an association of decreased epigenetic gene expression in HSATII repeat RNA high tumors. Conclusions: This proof-of-concept study demonstrates the safety and activity of single-agent 3TC. Repeat RNA levels appear to correlate with clinical benefit and can be measured in biopsies. Further combination studies and correlatives are planned. Clinical trial information: NCT03144804.

The role of circulating tumor DNA (ctDNA), tumor markers (TMs), and patient-reported outcomes (PROs) in predicting treatment response in patients with metastatic gastrointestinal (GI) cancer

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Background: Changes in ctDNA and serum TMs (CEA and CA19-9) can serve as predictors of response to systemic therapy in GI cancer patients (pts). Similarly, PROs correlate with survival and treatment response. We present a preliminary analysis of ctDNA, TMs, and PROs in predicting treatment response. Methods: We are enrolling 200 pts in a prospective study with metastatic pancreatic (PDAC), colorectal (CRC), gastroesophageal (GE), and biliary cancers. We are collecting ctDNA, TMs (CEA for all tumor types; CA19-9 for PDAC, GE, biliary), and PROs (FACT-G for QOL [higher scores indicate better QOL]; ESAS-r and PRO-CTCAE for symptoms; and PHQ-4 [consists of GAD-2 and PHQ-2 for anxiety and depression]; higher ESAS-r, PRO-CTCAE, and PHQ-4 scores reflect greater symptom burden) at baseline and 4 weeks. ctDNA is benchmarked against somatic tissue alterations, and serially assessed by digital droplet PCR. We correlated median percent change from baseline to 4 weeks for ctDNA, TMs, and PROs with treatment response (clinical benefit [CB], progressive disease [PD]). Results: From April to August 2019, we have enrolled 38/45 (84.4%) eligible pts (median age = 64 years; 36.8% female). Among these 38 pts, tumor types are PDAC (36.8%), CRC (31.6%), GE (28.9%), and biliary (2.6%). 18/38 pts were evaluable for ctDNA. Change in ctDNA was -94.5% in pts with CB (n = 10) and -19.5% in pts with PD (n = 8; p = 0.025). No correlation was observed between CEA and treatment response (p = 0.367). Change in CA19-9 was -1.5% for pts with CB and +47% for pts with PD (p = 0.019). Changes in PRO-CTCAE (p = 0.345), GAD-2 (p = 0.697), and ESAS scores (p = 0.743) did not differ between pts with CB and PD. However, changes in PHQ-2 (CB 0% v. PD +22.5%; p < 0.001), PHQ-4 (CB -8.5% v. PD +5%; p = 0.015), and FACT-G (CB +30% v. PD +5%; p = 0.049) were significant. Conclusions: Preliminary analysis suggests that ctDNA and PROs demonstrate promising utility for early prediction of treatment response, with favorable performance relative to standard TMs. Further analyses of larger pt numbers in this ongoing study may clarify the use and integration of these measures to better predict pt outcomes.

Predictors of Resectability and Survival in Patients With Borderline and Locally Advanced Pancreatic Cancer who Underwent Neoadjuvant Treatment With FOLFIRINOX

OBJECTIVE

The aim of this study was to determine (1) whether preoperative factors can predict resectability of borderline resectable (BR) and locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC) after neoadjuvant FOLFIRINOX, (2) which patients might benefit from adjuvant therapy, and (3) survival differences between resected BR/LA patients who received neoadjuvant FOLFIRINOX and upfront resected patients.

BACKGROUND

Patients with BR/LA PDAC are often treated with FOLFIRINOX to obtain a margin-negative resection, yet selection of patients for resection remains challenging.

METHODS

Clinicopathologic data of PDAC patients surgically explored between 04/2011-11/2016 in a single institution were retrospectively collected.

RESULTS

Following neoadjuvant FOLFIRINOX, 141 patients were surgically explored (BR: 49%, LA: 51%) and 110 (78%) were resected. Resected patients had lower preoperative CA 19-9 levels (21 vs 40 U/mL, P = 0.03) and smaller tumors on preoperative computed tomography (CT) scan (2.3 vs 3.0 cm, P = 0.03), but no predictors of resectability were identified. Median overall survival (OS) was 34.2 months from diagnosis for all FOLFIRINOX patients and 37.7 months for resected patients. Among resected patients, preoperative CA 19-9 >100 U/mL and >8 months between diagnosis and surgery predicted a shorter postoperative disease-free survival (DFS); Charlson comorbidity index >1, preoperative CA 19-9 >100 U/mL and tumor size (>3.0 cm on CT or >2.5 cm on pathology) predicted decreased OS. DFS and OS were significantly better for BR/LA PDAC patients treated with neoadjuvant FOLFIRINOX compared with upfront resected patients (DFS: 29.1 vs 13.7, P < 0.001; OS: 37.7 vs 25.1 months from diagnosis, P = 0.01).

CONCLUSION

BR/LA PDAC patients with no progression on neoadjuvant FOLFIRINOX should be offered surgical exploration. Except size, traditional pathological parameters fail to predict survival among resected FOLFIRINOX patients. Resected FOLFIRINOX patients have survival that appears to be superior than that of resectable patients who go directly to surgery.

A phase 2 clinical trial of the heat shock protein 90 (HSP 90) inhibitor ganetespib in patients with refractory advanced esophagogastric cancer

Subsets of esophagogastric (EG) cancers harbor genetic abnormalities, including amplification of HER2, MET, or FGFR2 or mutations in PIK3CA, EGFR, or BRAF. Ganetespib which is a novel triazolone heterocyclic inhibitor of HSP90, is a potentially biologically rational treatment strategy for advanced EG cancers with these gene amplification. This multicenter, single-arm phase 2 trial enrolled patients with histologically confirmed advanced EG cancer with progression on at least one line of systemic therapy. Patients received Ganetespib 200 mg/m2 IV on Days 1, 8, and 15 of a 28-day cycle. The primary endpoint was overall response rate (ORR). Secondary endpoints included: Progression Free Survival (PFS); to correlate the presence of HSP clients with ORR and PFS; evaluating the safety, tolerability and adverse events profile. In this study 26 eligible patients mainly: male 77%, median age 64 years were enrolled. The most common drug-related adverse events were diarrhea (77%), fatigue (65%), elevated ALKP (42%), and elevated AST (38%). The most common grade 3/4 AEs included: leucopenia (12%), fatigue (12%), diarrhea (8%), and elevated ALKP (8%). The ORR of 4% reflects the single patient of 26 who had a complete response and stayed on treatment for more than seventy (70) months. Median PFS and OS was 61 days (2.0 months), 94 days (3.1 months) respectively. Ganetespib showed manageable toxicity. While the study was terminated early due to insufficient evidence of single-agent activity, the durable CR and 2 minor responses suggest that there may be a subset of EG patients who could benefit from this drug.

Hypofractionated Radiation Therapy for Unresectable/Locally Recurrent Intrahepatic Cholangiocarcinoma

OBJECTIVE

The aim of this study was to evaluate outcomes for patients with unresectable intrahepatic cholangiocarcinoma (ICC) treated with hypofractionated proton or photon radiation therapy (HF-RT).

METHODS

We retrospectively identified 66 patients with ICC who were treated with HF-RT from 2008 to 2018. Median age at RT was 76 years (range 30-92), including 27 patients (41%) aged ≥ 80 years. Median RT dose was 58.05 Gy (range 37.5-67.5), all delivered in 15 daily fractions. Thirty-two patients received proton RT and 34 patients received photon RT.

RESULTS

Median follow-up times from diagnosis and RT start were 21 months and 14 months, respectively. In total, five patients (7.6%) developed local failure. The 2-year outcomes were 84% local control (LC) and 58% OS. Among the 51 patients treated with definitive intent, the 2-year LC rate was 93% and the OS rate was 62%. On multivariate analysis for LC, older age was associated with a lower risk of local failure [hazard ratio (HR) 0.91; p = 0.02], while prior surgery (HR 16.5; p = 0.04) and macrovascular invasion (HR 123.93; p = 0.02) were independently associated with an increased risk of local failure. On multivariate analysis for OS, female sex (HR 0.33; p = 0.001) and prior chemotherapy (HR 0.38; p = 0.003) remained significantly associated with OS. On multivariate analysis for OS, compared with photon RT, there was a trend towards improved survival with proton RT (HR 0.50; p = 0.05). The rate of overall grade 3 + toxicity was 11%. One patient developed radiation-induced liver disease and was treated with corticosteroids.

CONCLUSIONS

HF-RT yields high rates of local control and is an effective modality to optimize biliary control for unresectable/locally recurrent ICC.

Author Correction: Liquid versus tissue biopsy for detecting acquired resistance and tumor heterogeneity in gastrointestinal cancers

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Total Neoadjuvant Therapy With FOLFIRINOX Followed by Individualized Chemoradiotherapy for Borderline Resectable Pancreatic Adenocarcinoma: A Phase 2 Clinical Trial

Importance

Patients with borderline-resectable pancreatic ductal adenocarcinoma have historically poor outcomes with surgery followed by adjuvant chemotherapy. Evaluation of a total neoadjuvant approach with highly active therapy is warranted.

Objective

To evaluate the margin-negative (R0) resection rate in borderline-resectable pancreatic ductal adenocarcinoma after neoadjuvant FOLFIRINOX (fluorouracil, irinotecan, and oxaliplatin) therapy and individualized chemoradiotherapy.

Design, Setting, and Participants

A single-arm, phase 2 clinical trial was conducted at a large academic hospital with expertise in pancreatic surgery from August 3, 2012, through August 31, 2016, among 48 patients with newly diagnosed, previously untreated, localized pancreatic cancer determined to be borderline resectable by multidisciplinary review, who had Eastern Cooperative Oncology Group performance status 0 or 1 and adequate hematologic, renal, and hepatic function. Median follow-up for the analysis was 18.0 months among the 30 patients still alive at study completion.

Interventions

Patients received FOLFIRINOX for 8 cycles. Upon restaging, patients with resolution of vascular involvement received short-course chemoradiotherapy (5 Gy × 5 with protons) with capecitabine. Patients with persistent vascular involvement received long-course chemoradiotherapy with fluorouracil or capecitabine.

Main Outcomes and Measures

The primary outcome was R0 resection rate; secondary outcomes were median progression-free survival (PFS) and median overall survival (OS).

Results

Of the 48 eligible patients, 27 were men and 21 were women, with a median age of 62 years (range, 46-74 years). Of the 43 patients who planned to receive 8 preoperative cycles of chemotherapy, 34 (79%) were able to complete all cycles. Twenty-seven patients (56%) had short-course chemoradiotherapy, while 17 patients (35%) had long-course chemoradiotherapy. R0 resection was achieved in 31 of the 48 eligible patients (65%; 95% CI, 49%-78%). Among the 32 patients who underwent resection, the R0 resection rate was 97% (n = 31). Median PFS among all eligible patients was 14.7 months (95% CI, 10.5 to not reached), with 2-year PFS of 43%; median OS was 37.7 months (95% CI, 19.4 to not reached), with 2-year OS of 56%. Among patients who underwent resection, median PFS was 48.6 months (95% CI, 14.4 to not reached) and median OS has not been reached, with a 2-year PFS of 55% and a 2-year OS of 72%.

Conclusions and Relevance

Preoperative FOLFIRINOX followed by individualized chemoradiotherapy in borderline resectable pancreatic cancer results in high rates of R0 resection and prolonged median PFS and median OS, supporting ongoing phase 3 trials.

Trial Registration

ClinicalTrials.gov Identifier: NCT01591733.