Management of Older Adults With Colorectal Cancer: The Role of Geriatric Assessment

Older adults share a growing burden of cancer morbidity and mortality. This is present across the spectrum of oncologic diagnoses and is particularly true with colorectal cancer (CRC), where older adults continue to share the burden of diagnoses. However, optimal cancer treatment decision making in older adults remains a significant challenge, as the majority of previous clinical trials shaping the current treatment landscape have focused on younger patients, often with more robust performance status and fewer medical comorbid conditions. The heterogeneous aging process of older adults with CRC necessitates a personalized treatment approach, as approximately three-quarters of older adults with CRC also have a concominant geriatric syndrome and more than half of older adults with CRC are pre-frail or frail. Treatment decisions shoud be multifaceted, including consultation with the patient and their familes regarding their wishes, with consideration of the patient's quality of life, functional status, medical comorbid conditions, social support, and treatment toxicity risk. Geriatric assessment is a systematic and validated approach to assess an older adults's potential strengths and vulnerabilities, which can in turn be used to assist with comprehensive cancer care planning and support. In this review, we will summarize current treatment approaches for older adults with CRC, with a particular focus on the incorporation of the geriatric assessment.

Safety and Efficacy of Concurrent Atezolizumab/Bevacizumab or Nivolumab Combination Therapy with Yttrium-90 Radioembolization of Advanced Unresectable Hepatocellular Carcinoma

To evaluate the safety and efficacy of combining yttrium-90 radioembolization (Y90-RE) with immune checkpoint inhibitor therapy, consecutive advanced unresectable hepatocellular carcinoma (HCC) patients treated between 2016 and 2022 with atezolizumab/bevacizumab or nivolumab within three-months pre- and post-Y90-RE were retrospectively evaluated. Tumor response and treatment-related clinical/laboratory adverse events (AE) were assessed at 1 and 6 months, as well as differences in clinical and laboratory variables and median overall survival (OS) from initial treatment (whether it was Y90-RE or systemic therapy) between the two cohorts. A total of 19 patients (10 atezolizumab/bevacizumab; 9 nivolumab), comprising 84% males with median age 69 years, met the inclusion criteria. Compared to the atezolizumab/bevacizumab group, there were less males (100% vs. 67%; p = 0.02) and more ECOG ≥ 2 patients in the nivolumab group (0% vs. 33%; p = 0.02). Baseline characteristics or incidence of 6-month post-treatment any-grade AE (60% vs. 56%; p = 0.7), grade ≥ 3 AE (0% vs. 11%; p = 0.3), objective response (58% total, 60% vs. 56%; p = 0.7), and complete response (16% total; 10% vs. 22%; p = 0.8) were similar between the atezolizumab/bevacizumab and the nivolumab cohorts. Median OS was 12.9 months for the whole cohort, 16.4 months for nivolumab, and 10.7 months for atezolizumab/bevacizumab. Among patients with advanced unresectable HCC, the utilization of Y90-RE concurrently or within 90 days of nivolumab or atezolizumab/bevacizumab immunotherapy, appears to be well-tolerated and with a low incidence of severe AE.

Advances in Immunotherapy for Hepatocellular Carcinoma (HCC)

Hepatocellular carcinoma (HCC) is the second most common cause of cancer-related deaths in the world. More than half of patients with HCC present with advanced stage, and highly active systemic therapies are crucial for improving outcomes. Immune checkpoint inhibitor (ICI)-based therapies have emerged as novel therapy options for advanced HCC. Only one third of patients achieve an objective response with ICI-based therapies due to primary resistance or acquired resistance. The liver tumor microenvironment is naturally immunosuppressive, and specific mutations in cell signaling pathways allow the tumor to evade the immune response. Next, gene sequencing of the tumor tissue or circulating tumor DNA may delineate resistance mechanisms to ICI-based therapy and provide a rationale for novel combination therapies. In this review, we discuss the results of key clinical trials that have led to approval of ICI-based therapy options in advanced HCC and summarize the ongoing clinical trials. We review resistance mechanisms to ICIs and discuss how immunotherapies may be optimized based on the emerging research of tumor biomarkers and genomic alterations.

Implementation of the Web-Enabled Cancer & Aging Resilience Evaluation (WeCARE) in an outpatient oncology setting

INTRODUCTION

Although geriatric assessments (GAs) are recommended for use in older adults with cancer, their integration into oncology practice remain suboptimal. Here, we report our experience integrating web-enabled GA (WeCARE) into oncology practice as an augmented delivery method and provider interface format to overcome implementation barriers.

MATERIALS AND METHODS

Older patients (≥60 years) with a gastro-intestinal (GI) malignancy presenting for an initial visit to medical oncology clinic at a single institution between December 7, 2021 and October 10, 2022 were contacted by staff two days in advance of their visits and sent a link to the WeCARE GA, rather than the paper version used previously. Results were directly embedded into the medical record. We describe our initial implementation outcomes and the results of a provider usability survey.

RESULTS

Of 266 eligible patients, 221 (83.1%) were successfully contacted by telephone and 200 (75.2%) completed the WeCARE prior to their appointment. More than one phone call was required to make contact for 35.7% of patients, with a mean duration of phone conversation of 2.8 min. Most patients preferred email delivery to text (63% vs 31%); 4.5% were unable to access surveys due to inadequate technology, and 25.7% brought up additional logistical concerns. Among GI oncology providers surveyed, all six found the WeCARE tool and dashboard acceptable, appropriate, and feasible. However, only a third of providers often or always used the dashboard to inform treatment decisions and guide interventions.

DISCUSSION

With nearly three-quarters of patients completing the WeCARE prior to their visits with minimal staff support and time required, this method of administration may be a viable format to overcome barriers to GA implementation. Additional work is needed to integrate the results meaningfully into clinical practice.

Short Course Radiotherapy (SCRT) with Simultaneous Integrated Boost (SIB) in the Treatment of Rectal Cancer: Feasibility and Early Toxicities

PURPOSE/OBJECTIVE(S)

To report the feasibility and early toxicities of dose-escalated SCRT in rectal cancer patients receiving total neoadjuvant therapy (TNT).

MATERIALS/METHODS

This retrospective cohort study included 13 patients treated via a TNT approach (guided by RAPIDO trial) for locally advanced rectal cancer. The planned radiation was a standard dose of 25 Gy in 5 fractions to the primary tumor and at-risk lymphatics (PTV_Low). The dose-escalation was achieved via SIB delivering 30 Gy to the primary tumor (PTV_Mid) and 40 Gy (PTV_High) to inoperable lateral pelvic lymph nodes (LN), when present, over 5 fractions. A 5 mm margin was added to the rectal tumor and lateral pelvic LN to create the SIB targets. All patients were planned for intensity modulated radiation therapy via Varian EclipseTM (Palo Alto, CA) treatment planning system. Prior to treatment patients underwent kV and cone beam CT (CBCT) imaging for image guidance. Shifts were not performed solely to accommodate the boost target volume if it was felt to compromise the coverage of at-risk lymphatics. Normal tissue constraints were prioritized over boost coverage. Early toxicities were assessed for 30 days following treatment and graded using the Common Terminology Criteria for Adverse Events version 5.0. Offline image review was performed to determine the frequency at which the gross tumor volume (GTV) was captured within the 5 mm planning target volume (PTV_Mid) margin on daily CBCT scans. If a misalignment (tumor crossing outside of PTV_High) was discovered, the direction of misalignment (lateral/anterior/posterior) and location (superior/inferior) in relation to the superior border of the pubic symphysis was documented. An additional 5 mm margin from the PTV_Mid was created to determine if this would have captured the target.

RESULTS

Twelve of the 13 patients were ≥ 30 days from treatment completion and were included in the toxicity analysis. The most common grade 1-2 toxicities were proctitis and diarrhea, which occurred in 42% and 25% of patients, respectively. Other toxicities were new onset rectal bleeding (17%), rectal pain (17%) and radiation dermatitis (8%). No grade 3+ toxicities were observed. Given five fractions for each of the 13 patients, a total of 65 CBCTs were reviewed and compared to the planning CT obtained at simulation. A total of 14/65 (22%) misalignments were discovered across six patients. All occurred above the superior edge of the pubic symphysis. Four misalignments were multi-directional. Nine were anterior, 6 were lateral, and 1 was posterior. Twelve of the 14 (86%) would have been covered within the additional 5 mm expansion volume.

CONCLUSION

In this cohort of patients who received dose-escalated SCRT, the composite rate of acute toxicity was expectedly low. Feasibility of treatment delivery was established but could be improved upon with an addition 5 mm expansion, specifically in locations cranial to the superior edge of the pubic symphysis.

Phase II trial of nivolumab and metformin in patients with treatment-refractory microsatellite stable metastatic colorectal cancer

BACKGROUND

Preclinical studies showed metformin reduces exhaustion of tumor-infiltrating lymphocytes and potentiates programmed cell death protein-1 (PD-1) blockade. We hypothesized that metformin with nivolumab would elicit potent antitumor and immune modulatory activity in metastatic microsatellite stable (MSS) colorectal cancer (CRC). We evaluated this hypothesis in a phase II study.

METHODS

Nivolumab (480 mg) was administered intravenously every 4 weeks while metformin (1000 mg) was given orally, two times per day following a 14-day metformin only lead-in phase. Patients ≥18 years of age, with previously treated, stage IV MSS CRC, and Eastern Cooperative Oncology Group 0-1, having received no prior anti-PD-1 agent were eligible. The primary endpoint was overall response rate with secondary endpoints of overall survival (OS) and progression-free survival (PFS). Correlative studies using paired pretreatment/on-treatment biopsies and peripheral blood evaluated a series of immune biomarkers in the tumor microenvironment and systemic circulation using ChipCytometry and flow cytometry.

RESULTS

A total of 24 patients were enrolled, 6 patients were replaced per protocol, 18 patients had evaluable disease. Of the 18 evaluable patients, 11/18 (61%) were women and the median age was 58 (IQR 50-67). Two patients had stable disease, but no patients had objective response, hence the study was stopped for futility. Median OS and PFS was 5.2 months (95% CI (3.2 to 11.7)) and 2.3 months (95% CI (1.7 to 2.3)). Most common grade 3/4 toxicities: Anemia (n=2), diarrhea (n=2), and fever (n=2). Metformin alone failed to increase the infiltration of T-cell subsets in the tumor, but combined metformin and nivolumab increased percentages of tumor-infiltrating leukocytes (p=0.031). Dual treatment also increased Tim3+ levels in patient tissues and decreased naïve CD8+T cells (p=0.0475).

CONCLUSIONS

Nivolumab and metformin were well tolerated in patients with MSS CRC but had no evidence of efficacy. Correlative studies did not reveal an appreciable degree of immune modulation from metformin alone, but showed trends in tumorous T-cell infiltration as a result of dual metformin and PD-1 blockade despite progression in a majority of patients.

NEO-GAP: A Single-Arm, Phase II Feasibility Trial of Neoadjuvant Gemcitabine, Cisplatin, and Nab-Paclitaxel for Resectable, High-Risk Intrahepatic Cholangiocarcinoma

PURPOSE

Most patients with intrahepatic cholangiocarcinoma (IHCC) develop recurrence after resection. Adjuvant capecitabine remains the standard of care for resected IHCC. A combination of gemcitabine, cisplatin, and nab-paclitaxel (GAP) was associated with a 45% response rate and 20% conversion rate among patients with unresectable biliary tract cancers. The aim of this study was to evaluate the feasibility of delivering GAP in the neoadjuvant setting for resectable, high-risk IHCC.

METHODS

A multi-institutional, single-arm, phase II trial was conducted for patients with resectable, high-risk IHCC, defined as tumor size > 5 cm, multiple tumors, presence of radiographic major vascular invasion, or lymph node involvement. Patients received preoperative GAP (gemcitabine 800 mg/m2, cisplatin 25 mg/m2, and nab-paclitaxel 100 mg/m2 on days 1 and 8 of a 21-day cycle) for a total of 4 cycles prior to an attempt at curative-intent surgical resection. The primary endpoint was completion of both preoperative chemotherapy and surgical resection. Secondary endpoints were adverse events, radiologic response, recurrence-free survival (RFS), and overall survival (OS).

RESULTS

Thirty evaluable patients were enrolled. Median age was 60.5 years. Median follow-up for all patients was 17 months. Ten patients (33%) experienced grade ≥ 3 treatment-related adverse events, the most common being neutropenia and diarrhea; 50% required ≥ 1 dose reduction. The disease control rate was 90% (progressive disease: 10%, partial response: 23%, stable disease: 67%). There was zero treatment-related mortality. Twenty-two patients (73%, 90% CI 57-86; p = 0.008) completed all chemotherapy and surgery. Two patients (9%) who successfully underwent resection had minor postoperative complications. Median length of hospital stay was 4 days. Median RFS was 7.1 months. Median OS for the entire cohort was 24 months and was not reached in patients who underwent surgical resection.

CONCLUSION

Neoadjuvant treatment with gemcitabine, cisplatin, and nab-paclitaxel is feasible and safe prior to resection of intrahepatic cholangiocarcinoma and does not adversely impact perioperative outcomes.

Association of emotional support with quality of life, mental health, and survival in older adults with gastrointestinal malignancies-Results from the CARE registry

BACKGROUND

Emotional support (ES) is the most frequently reported support need among older adults with cancer. Yet, the association of ES with cancer outcomes is largely unknown. This study examined the association of ES with health-related quality of life (HRQoL), mental health, and survival among older adults with gastrointestinal (GI) malignancies.

METHODS

We included newly diagnosed older adults (≥60 years) with GI cancer undergoing self-reported geriatric assessment at their first clinic visit. ES was measured using an adaptation of the Medical Outcomes Study (dichotomized adequate ES vs. inadequate ES). Outcomes included physical and mental HRQoL, anxiety, depression, and survival. Multivariable linear regression evaluated the association between ES and HRQoL scores. Multivariable logistic regression evaluated the association of ES with anxiety and depression. All models were adjusted for age at geriatric assessments, race, sex, and cancer type/stage.

RESULTS

795 participants were included. Median patient age was 68 years (IQR: 64-74), 58% were male, and most cancers were either colorectal (37.9%) or pancreatic (30.8%). Most (77.6%) had adequate ES. Patients with inadequate ES were more likely to be Black (31.5 vs. 20.8%, p = 0.005), disabled (24.1 vs. 10.4%, p < 0.001), widowed/divorced (54.2 vs. 24.8%, p < 0.001) and had lower physical and mental HRQoL t-scores (Physical β: -3.35, 95% CI: -5.25, -1.46; Mental β: -2.46, 95% CI: -4.11, -0.81) and higher odds of depression (aOR: 2.22, CI: 1.34-3.69). This study found no difference between those with adequate ES versus inadequate ES in the proportion of deaths within 1 year of diagnosis (24.3% vs. 24.2%, p = 0.966), or within 2 years of diagnosis (32.4% vs. 33.2%, p = 0.126).

CONCLUSIONS

Older adults with inadequate ES have worse physical and mental HRQoL and higher odds of depression compared to those with adequate ES.

Use of Metformin and Survival in Patients with Hepatocellular Carcinoma (HCC) Undergoing Liver Directed Therapy: Analysis of a Nationwide Cancer Registry

BACKGROUND

Examine the association of metformin use and overall survival (OS) in patients with HCC undergoing image-guided liver-directed therapy (LDT): ablation, transarterial chemoembolization (TACE), or Yttrium-90 radioembolization (Y90 RE).

METHODS

Using National Cancer Institute Surveillance, Epidemiology, and End Results registry and Medicare claims databases between 2007 and 2016, we identified patients ≥ 66 years who underwent LDT within 30 days of HCC diagnosis. Patients with liver transplant, surgical resection, and other malignancies were excluded. Metformin use was identified by at least two prescription claims within 6 months before LDT. OS was measured by time between first LDT and death or last Medicare observation. Comparisons were performed between both all and diabetic patients on and not on metformin.

RESULTS

Of 2746 Medicare beneficiaries with HCC undergoing LDT, 1315 (47.9%) had diabetes or diabetes-related complications. Among all and diabetic patients, 433(15.8%) and 402 (30.6%) were on metformin respectively. Median OS was greater for patients on metformin (19.6 months, 95% CI 17.1-23.0) vs those not (16.0 months, 15.0-16.9; p = 0.0238). Patients on metformin had lower risk of death undergoing ablation (HR 0.70; 0.51-0.95; p = 0.0239) and TACE (HR 0.76, 0.66-0.87; p = 0.0001), but not Y90 RE (HR1.22, 0.89-1.69; p = 0.2231). Among diabetics, OS was greater for those on metformin vs those not (HR 0.77, 0.68-0.88; p < 0.0001). Diabetic patients on metformin had longer OS undergoing TACE (HR 0.71, 0.61-0.83; p < 0.0001), but not ablation (HR 0.74, 0.52-1.04; p = 0.0886) or Y90 RE (HR 1.26, 0.87-1.85; p = 0.2217).

CONCLUSION

Metformin use is associated with improved survival in HCC patients undergoing TACE and ablation.

Combinatorial targeting of immune checkpoints and epigenetic regulators for hepatocellular carcinoma therapy

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality worldwide. The five-year survival rate of patients with unresectable HCC is about 12%. The liver tumor microenvironment (TME) is immune tolerant and heavily infiltrated with immunosuppressive cells. Immune checkpoint inhibitors (ICIs), in some cases, can reverse tumor cell immune evasion and enhance antitumor immunity. Rapidly evolving ICIs have expanded systemic treatment options in advanced HCC; however, single-agent ICIs achieve a limited 15-20% objective response rate in advanced HCC. Therefore, other combinatorial approaches that amplify the efficacy of ICIs or suppress other tumor-promoting pathways may enhance clinical outcomes. Epigenetic alterations (e.g., changes in chromatin states and non-genetic DNA modifications) have been shown to drive HCC tumor growth and progression as well as their response to ICIs. Recent studies have combined ICIs and epigenetic inhibitors in preclinical and clinical settings to contain several cancers, including HCC. In this review, we outline current ICI treatments for HCC, the mechanism behind their successes and failures, and how ICIs can be combined with distinct epigenetic inhibitors to increase the durability of ICIs and potentially treat "immune-cold" HCC.

The association of the CARE Frailty Index with survival among older adults with pancreatic cancer

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Background: Outcomes of older adults with pancreatic cancer are highly variable with increased susceptibility to chemotherapy toxicities and inferior survival compared to younger patients. Determining which older adults are at higher risk for adverse outcomes remains a clinical challenge. We evaluated the association of a novel patient-reported geriatric assessment (GA)-based frailty index with survival among older adults with pancreatic cancer. Methods: Older adults (≥60y) referred for initial consultation at the UAB GI oncology clinic were prospectively enrolled in the Cancer and Aging Resilience Evaluation (CARE) registry. All patients underwent a patient-reported GA capturing multiple aging-related domains of health. The 44-item CARE frailty index (CARE-FI) based on the principles of deficit accumulation was utilized to determine frailty. The primary outcome was overall survival (OS) from the time of GA. Kaplan Meier method was used to estimate OS and comparisons between groups were by log-rank. A multivariate Cox regression model adjusted for age, sex, race, and cancer stage. Results: A total 254 older adults with pancreatic cancer were included; median age 70y, 52.4% male, 77% non-Hispanic white and 43.4% with stage IV disease. Overall, 40.1% (n=102) were frail, 26.0% (n=66) pre-frail and 33.9% (n=86) robust. No significant clinico-demographic differences across the 3 frailty groups were found. Differences in OS over two-year period was observed across the three frailty groups by the KM method ( p=0.008). In multivariate cox regression, frail status was associated with an increased risk of mortality (HR 1.9 [95% CI 1.19 – 2.98]; p=0.01) compared to robust status after adjustment for aforementioned confounders. Conclusions: The CARE-FI is a novel frailty index built on the principles of deficit accumulation using a patient-reported GA and is independently associated with survival among older adults with pancreatic cancer.[Table: see text]

Targeted therapy for intractable cancer on the basis of molecular profiles: An open-label, phase II basket trial (Long March Pathway)

Purpose

We evaluated he effects of molecular guided-targeted therapy for intractable cancer. Also, the epidemiology of druggable gene alterations in Chinese population was investigated.

Materials and methods

The Long March Pathway (ClinicalTrials.gov identifier: NCT03239015) is a non-randomized, open-label, phase II trial consisting of several basket studies examining the molecular profiles of intractable cancers in the Chinese population. The trial aimed to 1) evaluate the efficacy of targeted therapy for intractable cancer and 2) identify the molecular epidemiology of the tier II gene alterations among Chinese pan-cancer patients.

Results

In the first stage, molecular profiles of 520 intractable pan-cancer patients were identified, and 115 patients were identified to have tier II gene alterations. Then, 27 of these 115 patients received targeted therapy based on molecular profiles. The overall response rate (ORR) was 29.6% (8/27), and the disease control rate (DCR) was 44.4% (12/27). The median duration of response (DOR) was 4.80 months (95% CI, 3.33-27.2), and median progression-free survival (PFS) was 4.67 months (95% CI, 2.33-9.50). In the second stage, molecular epidemiology of 17,841 Chinese pan-cancer patients demonstrated that the frequency of tier II gene alterations across cancer types is 17.7%. Bladder cancer had the most tier-II alterations (26.1%), followed by breast cancer (22.4%), and non-small cell lung cancer (NSCLC; 20.2%).

Conclusion

The Long March Pathway trial demonstrated a significant clinical benefit for intractable cancer from molecular-guided targeted therapy in the Chinese population. The frequency of tier II gene alterations across cancer types supports the feasibility of molecular-guided targeted therapy under basket trials.

Survival and Prognostic Factors in Patients With Pancreatic Colloid Carcinoma Compared With Pancreatic Ductal Adenocarcinoma

OBJECTIVES

Colloid carcinoma (CC) is a rare subtype of pancreatic carcinoma. The aims of the study are to characterize the clinicopathological features and to evaluate the overall survival (OS) of patients with CC.

METHODS

Patients diagnosed with pancreatic CC and pancreatic ductal adenocarcinoma (PDAC) between 2004 and 2016 were identified from the National Cancer Database using International Classification of Disease-O-3 morphology (8480/3 and 8140/3) and topography (C25) codes. Kaplan-Meier analysis and Cox proportional hazards models were used to analyze OS.

RESULTS

Fifty-six thousand eight hundred forty-six patients were identified. A total of 2430 patients (4.3%) were diagnosed with pancreatic CC. Males constituted 52.8% of CC and 52.2% of PDAC. Colloid carcinoma presented with pathological stage I disease more often (16.7% vs 5.9%) and stage IV disease less often (42.1% vs 52.4%) than PDAC (P < 0.001). Stage I CC received chemotherapy (36.0% vs 59.4%) and neoadjuvant chemotherapy (4.4% vs 14.2%) less often compared with PDAC (P < 0.001). Statistically significant improved OS was seen among stage I, II, and IV CC compared with PDAC.

CONCLUSIONS

Pancreatic CC presented as stage I disease more often compared with PDAC. Neoadjuvant chemotherapy was administered more often in stage I PDAC compared with CC. Colloid carcinoma had improved OS compared with PDAC among all stages except stage III.

Role of local therapy in the management of patients with metastatic anal squamous cell carcinoma: a National Cancer Database study

BACKGROUND

About 10-20% of patients with anal squamous cell carcinoma (SCCa) present with metastatic disease and are usually treated with systemic chemotherapy. However, primary tumor control is crucial as local failure is associated with significant morbidity. Using the largest cohort to date, we report the impact of local therapy on survival among patients with metastatic anal SCCa.

METHODS

Data were collected from US hospitals that contributed to the National Cancer Database (NCDB) between 2004 and 2015. Patients who did not receive palliative systemic chemotherapy were excluded from analysis. Univariate (UVA) and multivariable analyses (MVA) were performed to identify factors associated with patient outcome. Kaplan-Meier analysis and Cox proportional hazards models were used to evaluate the association between tumor/patient characteristics and overall survival (OS).

RESULTS

A total of 1,160 patients were identified over the 12 years of study. Median age was 57 years. Majority were female (64.9%), non-Hispanic Whites (79.1%) and had Charlson-Deyo Score of 0 (83.6%). Most common metastatic sites were liver (25.9%), lung (11.6%) and bone (8.5%). More than 79% of the patients had received radiation to the primary site, and 10.4% underwent surgical resection for local control. Use of local therapy correlated closely with OS on MVA (HR 0.66; 0.55-0.79; P<0.001), with a 12-month and 5-year OS rates of 72.8% and 25.7% respectively, compared with 61.1% and 14.6% for patients treated with chemotherapy only. Poor prognostic factors included male gender (HR 1.44; 1.24-1.67; P<0.001), age >70 years (HR 1.28; 1.02-1.62; P=0.034), lack of health insurance (HR 1.32; 1.02-1.71; P=0.034), and cloacogenic zone location (HR 4.02; 1.43-11.30; P=0.008). There was no benefit from abdominoperineal resection (mOS =19.7 months; HR 1.05; 0.48-2.29; P=0.909), but both local resection of the primary (mOS =24.8 months, HR 0.48; 0.29-0.80; P=0.005) and palliative radiation (mOS =22.6 months; HR 0.66; 0.55-0.79; P<0.001) were associated with improved OS.

CONCLUSIONS

In addition to systemic therapy, resection of the primary tumor or palliative radiation improved OS in patients with anal SCCa. Patients unlikely to benefit from local control were those >70 years of age, male, lack of health insurance and cloacogenic carcinoma.

Abstract 3482: Correlative analysis of metformin and nivolumab combination in treatment-refractory microsatellite stable (MSS) metastatic colorectal cancer (mCRC)

Background: Preclinical results indicate that metformin can modulate immune cell populations in the tumor microenvironment of solid tumors by diminishing exhaustion of CD8+ tumor infiltrating cells and improving T cell responses. Studies also suggest that metformin could complement PD-1 blockade and potentiate its antitumor activity. Previously we reported the results of a phase II trial with metformin and nivolumab and here we report the findings of correlative analysis of the prospectively collected research samples of 18 patients.

Methods: We conducted a phase II trial with nivolumab and metformin in treatment-refractory microsatellite stable (MSS) metastatic colorectal cancer (mCRC). Nivolumab 480 mg IV every 4 weeks and metformin 1000 mg orally twice daily was administered in 28-day cycles following a 14-day metformin only lead-in phase. The primary endpoint was overall response rate (ORR). Secondary endpoints were overall survival (OS) and progression free survival (PFS). Pre-treatment and on-treatment research biopsies and correlative peripheral blood specimens were collected. Paired biopsies obtained at baseline and following treatment with metformin only (n=9) or metformin and nivolumab (n=9) and were stained with a panel of 13 markers using ChipCytometry technology by Canopy Biosciences. Sample was assessed prior to establishing the multiplex assay. 30 out of 36 samples were imaged and analyzed up to 30 Fields of View. Single cell recognition and quantitative biomarker analysis were performed to compare immune cell numbers and population distribution in pre- versus post-treatment samples.

Results: As previously reported, no patients had objective response based on RECIST version 1.1 and the study was stopped after the first stage for futility. Median OS and PFS was 5.1 months [95% CI (2-11.7)] and 2.3 months [95% CI (1.7-2.4)], respectively. Multiplex analysis of tissues from patients receiving lead in with metformin alone revealed fewer effector CD4 T cells and effector and effector memory CD8 T cells after treatment vs. baseline biopsy. Biopsy tissue from patients treated with metformin and nivolumab had lower pAMPK and decreased PDL-1 expression vs. baseline. The combination also increased percentages of leukocytes, effector CD4 T cells, effector and effector memory CD8 T cells as well as levels of PDL1-Tim3+ cells.

Conclusion: In the setting of MSS mCRC, metformin as a single agent did not enhance effector CD4 and CD8 T cell percentages in clinical samples in our patient cohort. Metformin in combination with nivolumab was associated with increased percentages of effector CD4 and CD8 T cells in biopsy specimens, although these improvements did not translate into enhanced clinical endpoints. Analysis of peripheral blood samples are currently underway to corroborate the findings in the tissue samples.

Citation Format: Batoul Farran, Jeffrey M. Switchenko, Lana Khalil, Walid L. Shaib, Brian Olson, Amanda Ruggieri, Christina Wu, Olatunji B. Alese, Maria Diab, Gregory B. Lesinski, Bassel El-Rayes, Mehmet Akce. Correlative analysis of metformin and nivolumab combination in treatment-refractory microsatellite stable (MSS) metastatic colorectal cancer (mCRC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3482.

Abstract 6274: Prognostic impact of Sarcopenia on clinical outcomes in advanced hepatocellular carcinoma (HCC) treated with systemic therapy

Background: Sarcopenia is one of the early pathological features of cancer cachexia, yet the effect of sarcopenia on clinical outcomes in patients with advanced HCC is unclear. Our objective was to determine the effect of Sarcopenia on response to systemic therapy with advanced HCC.

Methods: Patients with unresectable and advanced liver cancer were retrospectively evaluated between 2010 to 2019. Skeletal muscle area (SMA) was computed with a previously validated computed tomography (CT) body composition AI algorithm. The skeletal muscle index (SMI) was derived from the skeletal muscle area (SMA) (cm2) divided by patient height (m2) calculated from images at the level of L3 on pretreatment CT. Sarcopenia cutoffs for females was less than 39 cm2/m2 SMI or less than 50 cm2/m2 SMI for males. Patients’ demographics, systemic treatment response, toxicity, progression-free survival (PFS) and overall survival (OS) were compared between first-line therapy groups. Kaplan-Meier and Cox proportional hazards regression were used for survival analysis comparisons.

Results: A total of 146 patients with advanced HCC were assessed from Mayo Clinic Arizona and Emory University. Seventy-six patients received immunotherapy as first-line treatment and seventy patients received TKI as first-line therapy. Sarcopenia at baseline was assessed in a total of 91 patients at first-line systemic treatment: n=48 with immunotherapy (IO) and n=43 with tyrosine kinase inhibitor (TKI). Sarcopenia was more prevalent in male patients (p=0.009), and in patients with low BMI (p=0.02). When comparing those with sarcopenia at baseline, higher response rate was observed in patients treated with IO without sarcopenia (47% versus 15%, p=0.019), this was not observed in TKI group. Interestingly, median PFS and OS was not significantly changed in patients with or without sarcopenia treated with IO or TKI on first-line therapy.

Conclusions: Sarcopenia was associated with reduced response rate (RR) in patients treated with IO, but not in TKI groups. Both didn’t translate into deleterious effect in PFS and or OS. Further research with sufficient adjustments for confounding factors is warranted to better elucidate the prognostic value of sarcopenia in these patients.

Citation Format: Gehan Botrus, Pedro Luiz Serrano Uson Junior, Heidi Kosiorek, Mehmet Akce, Isabela Chang, Zhubene Mesbah, Eric Yancey, Daniel Blezek, Jason Klug, Lana Khalil, Puneet Raman, Mohamad Sonbol, Mitesh Borad, Daniel Ahn, Tanios Bekaii-Saab. Prognostic impact of Sarcopenia on clinical outcomes in advanced hepatocellular carcinoma (HCC) treated with systemic therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6274.

A phase 1 multiple-ascending dose study to evaluate the safety and tolerability of XmAb23104 (PD-1 x ICOS) in subjects with selected advanced solid tumors (DUET-3)

2604

Background: XmAb23104 is a bispecific antibody targeting T cells that simultaneously express PD-1, an immune checkpoint, and ICOS, a costimulatory molecule expressed after T cell activation. DUET-3 is a Phase 1, first-in-human, dose-escalation and expansion study in subjects with advanced solid tumors, designed to assess safety, tolerability and to identify the maximum tolerated dose (MTD) of XmAb23104. Secondary objectives are to assess pharmacokinetics (PK), immunogenicity, and preliminary anti-tumor activity. We report preliminary data from the completed dose-escalation phase. Methods: A 3+3 monotherapy dose escalation with 9 dose levels from 0.002 to 15 mg/kg has been completed. Subjects with measurable disease who progressed on prior standard therapy were eligible. A minimum 6-week washout from prior pembrolizumab was required. XmAb23104 was administered biweekly and RECIST 1.1 assessment was performed every 8 weeks. Results: Sixty-two subjects were treated in escalation at doses up to 15 mg/kg; no dose-limiting toxicities were observed and an MTD was not reached. These subjects had advanced disease, 92% were Stage IV at screening, the median number of prior therapies was 3, and 37% had previous checkpoint therapy. Thirty-seven subjects (59.7%) experienced a treatment-related adverse event (TRAE); the most common were diarrhea (9.7%), decreased appetite (9.7%), and fatigue (9.7%). The majority of TRAEs were Grades 1 or 2, with 6 subjects (9.7%) having a Grade 3 or higher TRAE. Thirteen immunotherapy-related adverse events (irAEs) occurred in 8 subjects; no individual irAE occurred in more than 1 subject. Most irAEs were mild (Grades 1 and 2) with 1 Grade 3 pruritus and 1 asymptomatic Grade 4 lipase elevation. Partial responses were observed in 3 subjects (sarcoma; prior PD-1 head and neck squamous cell carcinoma [HNSCC] and renal cell carcinoma [RCC]), and stable disease > 12 months was observed in 2 subjects with colorectal cancer (CRC; 1 MSS and 1 MSI-H). A dose of 10 mg/kg was selected after consideration of PK, safety, and clinical activity data in consultation with the investigators and continues to be evaluated in the expansion part of the study. Conclusions: The dose escalation part of this study indicates XmAb23104 was generally well tolerated at doses up to 15 mg/kg and has shown clinical activity in subjects with advanced solid tumors. CTLA4 blockade has been found to increase the frequency of ICOS-expressing T cells in prostate cancer, bladder cancer, melanoma, and hepatocellular cancer (Chen, 2009; Liakou, 2008; Wei, 2017) and may be applicable to other immunogenic tumor types. XmAb23104 is currently being studied alone or in combination with ipilimumab in expansion in non-squamous non-small cell lung carcinoma, melanoma, CRC, undifferentiated pleomorphic sarcoma, HNSCC, and RCC. Clinical trial information: NCT03752398.

NEO-GAP: A phase II single-arm prospective feasibility study of neoadjuvant gemcitabine/cisplatin/nab-paclitaxel for resectable high-risk intrahepatic cholangiocarcinoma

4097

Background: Given a high recurrence rate, surgical resection for localized intrahepatic cholangiocarcinoma (IHCC) is curative in only 30-35% of patients. BILCAP has established a standard of care for adjuvant therapy with monotherapy capecitabine. Gemcitabine, cisplatin and nab-paclitaxel combination chemotherapy (GAP) was associated with a response rate of 45% in biliary cancer and 20% of patients who were previously inoperable underwent margin negative resection. Based on these data, we conducted a neoadjuvant study of GAP for resectable but high-risk IHCC. Methods: A multi-institutional prospective single-arm phase II trial was conducted for patients with resectable high-risk disease, as defined by tumor size > 5cm, multiple tumors, presence of radiographic major vascular invasion, and lymph node involvement. Patients were administered 4 cycles (3 months) of preoperative GAP (gemcitabine 800 mg/m2, cisplatin 25 mg/m2 and nab-paclitaxel 100 mg/m2 on days 1 and 8 of a 21-day cycle) prior to an attempt at curative-intent surgical resection. The primary endpoint was completion of all therapy, including both preoperative chemotherapy and resection. Secondary endpoints were toxicity, radiologic response according to Response Evaluation Criteria in Solid Tumor (RECIST) criteria, RFS, and OS. Thirty evaluable patients provided 73% power to reject a null therapy completion rate of 50%, with a target completion rate of 70% using a one-sided exact test with a Type I error of 0.05. Results: Thirty-seven patients were screened and 30 evaluable patients were enrolled. The trial was sequentially activated at each of the 4 sites from 09/18-02/21 and the final patient was enrolled in 09/21. Median age was 60.5 years and 40% were female. Twenty-three patients (77%, 90% CI: 60.6-88.5%; p = 0.0026) completed all preoperative chemotherapy and underwent surgical resection. Ten patients (33%) experienced grade 3-4 treatment-related adverse events, the most common being neutropenia and diarrhea; 47% required at least one dose reduction. Partial response rate was 23% and disease control rate was 90% (PD: 10%, PR: 23%, SD: 67%). Of the 23 patients who successfully underwent surgical resection, 2 (9%) had minor postoperative complications. Median size of largest tumor was 5.5cm, median number of tumors was 3, and 39% were lymph node positive. Median length of hospital stay was 4 days. There was zero treatment related mortality. Conclusions: This study met its primary endpoint and demonstrated that neoadjuvant gemcitabine/cisplatin/nab-paclitaxel is feasible and safe prior to resection of intrahepatic cholangiocarcinoma and does not adversely impact perioperative outcomes. Continued follow-up for RFS and OS with this treatment strategy is underway and larger validation studies are planned. Clinical trial information: NCT03579771.

Telotristat ethyl with PRRT in the treatment of well differentiated neuroendocrine tumors

e16205

Background: Feasibility of telotristat ethyl, a tryptophan hydroxylase inhibitor in serotonin synthesis, in combination with PRRT/lutetium Lu 177 DOTATATE is unclear in well differentiated neuroendocrine tumors (WDNET). We explore real world treatment patterns in patients receiving telotristat and PRRT. Methods: A retrospective study was conducted on 67 patients with a histopathologic diagnosis of WDNET, treated with telotristat and/or PRRT at the Winship Cancer Institute in Emory University from 2018 to 2022. OS and PFS were assessed by Kaplan Meier curves. Descriptive analysis was performed with associations characterized by multi- (MVA) and univariate (UVA) Cox proportional hazards model, t-test, and ANOVA. Results: Of the 67 patients, 44 received PRRT alone and 23 received PRRT with telotristat for carcinoid symptoms. Median age was 69 (range 18-80) with male 57% and white race 65%. 16 (26%), 41 (67%), 4 (7%) had grades 1 (Ki67 < 3%), 2 (3-20%), and 3 (> 20%) disease respectively. The plurality (n = 31, 46%) had primary small bowel (SB) NETs and 40 (65%) underwent primary NET resection. 2 had gastrinomas, 1 VIPoma, and 1 insulinoma. All had liver and 23 (40%) had bone metastases. Most patients received PRRT as 3rd line therapy. 59 (88%) in the entire cohort and 17 (74%) in the telotristat group received 4 doses of PRRT. 15 (17%) in the entire cohort had delayed/dose reduced PRRT. Telotristat was associated with improved diarrhea and decreased serotonin (all p < 0.003). 16 (70%) on telotristat reported improvement in diarrhea and flushing. 5 (17%) had grade 3/4 adverse events while receiving telotristat. Of those, 1 developed hypotension, 1 hypokalemia, 1 myelodysplastic syndrome, 1 febrile neutropenia, and 1 anemia and pursued hospice care after a cerebrovascular event. Median(m) OS, PFS, and follow up were 216, 33, 67 months (mo) for the entire cohort respectively. 6 (26%) died in the telotristat/PRRT group vs 17 (39%) PRRT only. 10 (43%) in the telotristat group progressed vs 18 (41%) in PRRT only. mPFS was 33 mo in telotristat/PRRT and not reached (NR) in PRRT only (p = 0.684). mOS was NR in the telotristat/PRRT group vs 216 mo in PRRT only (p = 0.717). In MVA, OS was associated with primary NET resection (HR 0.232), age > 60 (HR 7.88), SB primary NET (HR 0.097), and PRRT completion (HR 0.062, all p < 0.05). In MVA, PFS was associated with diarrhea (HR 3.7) and small bowel primary NET (HR 0.264, all p < 0.05). In UVA, lower OS and PFS were associated with elevated chromogranin A (CGA) (upper limit 225, HR 3.34, p < 0.02). Initial neutrophil-eosinophil ratio (NER) was associated with OS (HR 21.2) and PFS (HR 10.8) in MVA with optimal cutoff of 35.28 ( both p < 0.02). Conclusions: Patients with primary SB WDNETs and carcinoid symptoms benefited from receiving telotristat/PRRT in our study. CGA, serotonin, and NER are potential biomarkers to assess disease patterns. Multi-institutional studies and further follow up are needed to confirm these findings.

Impact of metformin on clinical outcomes in advanced hepatocellular carcinoma treated with immune checkpoint inhibitors

4118

Background: Non-alcoholic steatohepatitis (NASH) is an emerging etiology for hepatocellular carcinoma (HCC) and contributes to the increasing incidence of HCC worldwide. Patients with NASH often have risk factors of metabolic syndrome including hypertension, obesity, and type 2 diabetes (T2DM). NASH induced HCC has been shown to be associated with less response to immune check point inhibitors (ICIs) in HCC. Anti-diabetic agent metformin has been shown to be associated with improved outcomes in patients treated with ICIs in melanoma and non-small cell lung cancer. However, the impact of metformin on the efficacy of ICIs is not well defined in HCC. The main purpose of this study was to examine the effect of metformin on clinical outcomes in patients with advanced HCC treated with ICIs. Methods: We performed a retrospective analysis of patients with advanced HCC treated with ICIs in first and later-line settings between 2015 and 2021. The primary endpoints were overall survival (OS), progression free survival (PFS), and objective response rate (ORR) as assessed according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Patients were stratified based on their usage of metformin. OS and PFS were analyzed using Cox proportional hazard models and Kaplan-Meier analysis with log-rank test. Results: A total of 111 patients met inclusion criteria, 18 patients in the metformin group and 93 patients in the non-metformin group. Most common cause of HCC was viral hepatitis (52%), followed by NASH (29%), alcohol (8%) and other (11%). Baseline characteristics between the two groups were similar except all patients in the metformin group had a diagnosis of T2DM. ORR was 5.6%. (1 partial response) in the metformin group vs 22.6% (5 complete responses, 16 partial responses) in the non-metformin group. Median OS was 45.9 months in the non-metformin group vs 10.8 months in metformin group (HR 1.99, 95% CI 0.95-4.21, p = 0.064). Median PFS of 6.6 months vs 2.5 months (HR 1.75, 95% CI 0.93-3.29, p = 0.077). Moreover, metformin usage was associated with shorter median OS of 10.8 months (HR 1.96, 95% CI 0.75-5.09, p = 0.16) vs 20.9 months among patients with T2DM. OS was significantly worse in patients with poor ECOG performance status 2-3, MELD score 10-23, higher grade tumor histology, AFP > = 400, and use of IO in later lines of therapy. Conclusions: In this retrospective study metformin use was associated with worse clinical outcomes in advanced HCC patients treated with ICIs.

Trial in progress: Phase I study of SY-5609, a potent, selective CDK7 inhibitor, with initial expansion in adults with metastatic pancreatic cancer

TPS4180

Background: SY-5609 is an oral, selective, potent CDK7 inhibitor that targets two fundamental processes in cancer: transcription and cell cycle control. Early results from the Phase 1 dose escalation portion in patients (pts) with advanced solid tumors reported improved tolerability of the intermittent 7 days on followed by 7 days off (7/7) schedule with ongoing dose escalation beyond the continuous daily dosing maximum tolerated dose. Single-agent clinical activity was demonstrated with durable stable disease, target lesion regressions, and reduction in tumor markers observed in multiple tumor types, notably in pancreatic cancer with a disease control rate (DCR) of 38.5% (Sharma 2021). Pancreatic ductal adenocarcinoma (PDAC) has a 5-year survival rate of 11% (ACS Cancer Facts and figures, 2022) with limited treatment options and therefore, is a disease in need of novel effective therapies. Oncogenic KRAS mutations are prevalent in PDAC. Mutant KRAS is a potent stimulator of mitogenic MAPK signaling and downstream transcriptional programs for cell proliferation. Preclinical studies have shown that CDK7 inhibition via SY-5609 inhibits tumor growth in KRAS mutant PDAC xenograft models, in many cases leading to regressions. SY-5609 also potentiates gemcitabine (gem) activity in PDAC cells in vitro and in xenografts in vivo (Henry 2021). Therefore, combining SY-5609 with gem +/- nab-paclitaxel (nab-pac) offers a potential new treatment strategy for metastatic PDAC (mPDAC). The expansion portion of this Phase 1 study will evaluate SY-5609 in combination with gem +/- nab-pac in mPDAC pts. Gem +/- nab-pac will be administered on a biweekly schedule as it has shown better tolerability and similar clinical activity compared to the standard of care (SOC) administration schedule (Rehman 2020). Methods: This is an ongoing Phase 1, multi-center study in select solid tumors, amended to open expansion cohorts for mPDAC and expected to enroll approximately 80 mPDAC pts who have progressed on SOC treatments. Objectives of the expansion cohorts include evaluation of safety and efficacy of SY-5609 in combination with gem +/- nab-pac. Key objectives of the two parallel safety lead-in cohorts 1) SY-5609 + gem and 2) SY-5609 + gem + nab-pac are safety and determination of the recommended combination dose of the doublet and triplet for subsequent cohort expansions using a 3+3 escalation design. Key objectives of expansion cohorts are to describe efficacy, defined by progression-free survival, overall response rate, and DCR. Additional objectives include evaluation of pharmacokinetics and pharmacodynamics of SY-5609 in combination with gem +/- nab-pac. SY-5609 will be administered orally once daily on a 7/7 regimen and gem +/- nab-pac will be administered intravenously, in a 4-week cycle. The expansion portion is now open to enrollment. Clinical trial information: NCT04247126.

Successful liver transplantation of recurrent fibrolamellar carcinoma following clinical and pathologic complete response to triple immunochemotherapy: A case report

INTRODUCTION

Fibrolamellar carcinoma (FLC) is a rare liver cancer that predominantly affects younger patients without a history of liver disease. Surgical resection is the cornerstone of therapy and represents the best potentially curative treatment option. Modest objective responses with cytotoxic chemotherapy alone or combined with immune checkpoint inhibitors (ICIs) have been reported, however there are no established systemic therapy regimens for unresectable or metastatic FLC.

CASE PRESENTATION

We report a case of a 23-year-old woman with FLC who presented with a 11.5 x 8.3 cm left liver mass and subsequently underwent resection as initial therapy. Molecular analysis of her surgical tissue revealed a DNAJB1-PRKACA fusion gene. The patient developed biopsy-proven recurrent FLC with multiple liver lesions but without any distant metastatic disease only 3 months after initial resection. In light of emerging data, the patient was treated with a novel triple therapy regimen including 5-fluorouracil (5-FU), interferon (IFN) alfa-2b, and nivolumab. Partial radiographic response was achieved after 4 treatments and complete response was achieved after 12 cycles with the combination. The patient received 2 more doses of 5-FU/IFN alfa-2b without nivolumab, and underwent orthotopic liver transplantation (OLT) 6 months after the last dose of ICI. Pathological examination of the explanted liver remarkably confirmed pathologic complete response. She remains recurrence-free and is on active surveillance.

DISCUSSION/CONCLUSION

For patients with unresectable/recurrent FLC with no distant disease, the combination of 5-FU, IFN alfa-2b, and nivolumab could be an effective systemic therapy option. The use of this chemoimmunotherapy regimen to downstage FLC prior to OLT may be worth investigating further.

Frontline therapy for advanced hepatocellular carcinoma: an update

Hepatocellular carcinoma (HCC) is the fastest increasing cause of cancer-related mortality in the United States and is projected to be the third leading cause of cancer-related mortality in the United States by 2030. Main risk factors include alcoholic cirrhosis, chronic hepatitis B, hepatitis C, and nonalcoholic steatohepatitis (NASH). More than half of the patients have advanced-stage disease at presentation. Currently approved frontline systemic therapy options include sorafenib, lenvatinib, and atezolizumab/bevacizumab. Over the past decade, there has been a significant improvement in survival with a median overall survival of 19.2 months reported with first-line treatment with atezolizumab/bevacizumab. Based on positive results of randomized phase III HIMALAYA trial, durvalumab and tremelimumab combination could become another frontline option. Multiple frontline clinical trials with immune checkpoint inhibitor (ICI) or ICI combined with other novel agents are underway. In the frontline setting, identifying predictive biomarkers for ICI-based or tyrosine kinase (TKI)-based therapy is an unmet need. Subsequent treatment is poorly defined in patients with prior ICI-based therapy since all the available second-line and beyond therapy was studied after first-line sorafenib. Frontline systemic therapy is poorly defined in certain subgroups of HCC such as Child-Pugh B and post-transplant recurrent HCC. The landscape of frontline HCC treatment is rapidly changing, and this article reviews the most recent treatment approaches to frontline therapy for advanced HCC.

Rapidly Evolving Landscape and Future Horizons in Hepatocellular Carcinoma in the Era of Immuno-Oncology

Hepatocellular carcinoma (HCC) is a serious global health problem as one of the leading causes of cancer-related death worldwide. Systemic therapy for advanced HCC has progressed with the development of molecular targeted agents, however survival benefits remain modest. More recently, immune checkpoint inhibitors (ICI) have emerged and exhibited promising therapeutic benefits in a subset of patients. Physiologically, the intrinsic microenvironment in the liver is immunosuppressive, which represents a major obstacle for effective immune therapies in primary and secondary liver malignancies. For this reason, combination therapies that can overcome immune inhibitory mechanisms and enhance the immune response are a rationale approach for drug development in HCC. A recent example is the combination of the anti-PD-L1 antibody (atezolizumab) and anti-VEGF-A antibody (bevacizumab), which has shown significant improvement in survival as compared to standard of care in the first-line treatment for HCC. Other immunotherapy approaches including cancer vaccines and adoptive cell therapy are also under investigation. This review summarizes the key trials leading to our current HCC treatment options and provides an overview of future immune-based strategies in development.

Evolving Role of Immunotherapy in Advanced Biliary Tract Cancers

Simple Summary

Biliary tract cancers (BTC) include gallbladder cancers, intrahepatic, perihilar and distal extrahepatic cholangiocarcinomas. BTCs represent a major health problem due to their increasing global incidence and associated poor prognosis. The majority of patients present with advanced stages of cancer, where cytotoxic chemotherapy provides modest survival benefit. More recently, novel treatment options have emerged with the development of agents targeting specific genetic mutations of tumors as well as immunotherapy, which enhances the immune system’s ability to target cancer cells efficiently. In this review, we will discuss current and emerging systemic therapy options and the rationale for immunotherapy in BTC.

Abstract

Biliary tract cancers (BTC) comprise a rare and diverse group of malignancies that involve the gallbladder and biliary tree. These cancers typically present in later stages because they are aggressive in nature and affected patients are often asymptomatic in earlier stages of disease. Moreover, BTCs are generally refractory to cytotoxic chemotherapy, which further contributes to their associated poor survival outcomes. Novel therapy approaches are clearly needed. Molecular targeted agents have been developed based on our expanding knowledge of the genetic mutations underlying BTCs and represent a promising treatment strategy in molecularly selected subgroups of patients. In addition, the advent of immunotherapy over recent years has dramatically changed the bleak outcomes observed in malignancies such as melanoma. Our growing understanding of the complex tumor microenvironment in BTC has identified mechanisms of tumor immune evasion that could potentially be targeted with immunotherapy. As a result, different immunotherapeutic approaches including immune checkpoint inhibitors, cancer vaccines, and adoptive cell therapy, have been investigated. The use of immunotherapeutic agents is currently only approved for a small subset of treatment-refractory BTCs based on microsatellite instability (MSI) status and tumor mutational burden (TMB), but this will likely change with the potential approval of immunotherapy plus chemotherapy as a result of the TOPAZ-1 trial.

Characteristics and outcomes of patients with multiple synchronous colon cancer primaries

194

Background: Patients (pts) with multiple synchronous colon cancer primaries (MCPs) constitute a unique subset of pts with colon cancer. However, there are limited published studies about these pts. The objective of this study is to compare the characteristics and outcomes of pts with MCPs to those with single colon cancer primaries (SCPs) using the largest study population to date. Methods: Data was obtained from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Pts with synchronous MCPs were included and were matched 1:3 with pts with SCPs based on the Coarsened Exact Matching method for age, gender, and race. Only patients with multiple synchronous primaries were included (time since index = 0 months). We excluded pts with a lag time since diagnosis of index primary of 1 month or more. Univariate (UNA) and multivariable (MVA) analyses were performed to identify factors associated with patient outcomes. Kaplan-Meier analyses and Cox proportional hazards models were used to assess the association between tumor/patient characteristics and overall survival (OS). Results: A total of 3322 pts with MCPs and 9966 pts with SCPs were identified. Median age was 71 years. Majority were male (51.5%) and White (80.1%). 73.4% and 69.6% of pts had 12 or more lymph nodes examined for the MCPs and SCPs cohorts, respectively. The SCPs cohort included more T4 stage and more well- and moderately-differentiated histology. OS was significantly shorter in MCPs compared to SCPs (HR 1.29; 1.22-1.36; p < 0.001), with a 5- and 10-year OS rate of 47.8% and 28.2% for the MCPs and 56.4% and 41.6% for the SCPs, respectively, for all stages combined. In the MCPs cohort, the use of adjuvant chemotherapy was associated with an improved survival in AJCC stages II, III, and IV but not stage I. Conclusions: This is the largest study evaluating the impact of MCPs on outcomes. Across stages II to IV, pts with MCPs have a shorter survival than those with SCPs. Pts with stage II MCPs who receive adjuvant chemotherapy derive a survival benefit. Current guidelines do not list multiple synchronous primaries as a high-risk feature for stage II.

A randomized phase II trial of MEK and CDK4/6 inhibitors vesus tipiracil/trifluridine (TAS-102) in metastatic KRAS/NRAS mutant (mut) colorectal cancer (CRC)

116

Background: Constitutively activating KRAS or NRAS muts occur in ̃50% of CRC, increasing RAF-MEK-ERK signaling and causing overexpression of cyclin D1, which binds to cyclin dependent kinase 4/6 (CDK4/6) to drive cell cycle progression. Combination MEK and CDK4/6 inhibitors caused tumor regression in patient-derived xenografts of KRAS mut CRC. We hypothesized that binimetinib and palbociclib (B+P) would improve progression-free survival (PFS) compared to TAS-102 in refractory KRAS/NRAS mut mCRC. Methods: ACCRU-GI-1618 was a multicenter, randomized phase II clinical trial (NCT03981614). Key inclusion criteria were KRAS/NRAS mut mCRC, with prior fluoropyrimidine/ oxaliplatin/ irinotecan/ anti-VEGF therapy. There was a 6-patient safety run-in with binimetinib 30 mg po BID D1-28 and palbociclib 100 mg po daily D1-21. After, patients were randomized 1:1 to B+P vs TAS-102 (stratified by KRAS mut type and prior regorafenib use), with optional crossover at progression. The primary endpoint was PFS; 73 PFS events (from a sample size of 112) provided 90% power to detect improvement of PFS (hazard ratio = 0.5, i.e. median PFS of 2 vs. 4 months) with 1-sided α = 0.05. A prespecified interim analysis for futility was planned after 37 PFS events were observed, with completion of accrual if 1-sided stratified log-rank p-value < 0.551. Hazard ratios (HR) and 95% confidence intervals (CI) are estimated by stratified Cox proportional hazards models. Results: After the safety run-in, 93 patients at 6 sites were randomized; 82 (41 B+P, 41 TAS-102) comprise the primary analysis population (eligible, consented, and started treatment). In this population, median age was 52 years, 50% female, 68% left-sided, 79% with KRAS codon 12/13 mut, 12% with prior regorafenib. Enrollment was halted at interim analysis as the futility boundary was crossed (1-sided p = 0.67). At final analysis, 68 subjects had a PFS event (34 in each arm). Median PFS was 2.1 mo (95% CI 2.0-3.0) with B+P vs 2.1 mo (2.0-2.4) with TAS-102; HR 0.86 (0.52-1.44). 4-mo PFS rate was 22.2% (11.9-41.6) with B+P vs 10.6% (3.8-30.0) with TAS-102. With 37 OS events (14 in B+P arm), median OS was 7.7 mo (5.1-NE) with B+P vs 6.6 mo (4.8-8.9) with TAS-102; HR 0.77 (95% CI 0.39-1.51). TAS-102 had greater grade 3-4 hematologic AEs (46% vs 22%), and B+P had more grade 3-4 non-hematologic AEs (47% vs 32%). Grade 3-4 AEs more common with B+P were fatigue (8% vs 0%), oral mucositis (6% vs 0%), and nausea (4% vs 2%). Though 63% of patients on B+P had acneiform rash, only 2% was grade 3-4. Grade 1-2 diarrhea occurred in 35% of B+P and 24% of TAS-102 patients. No new safety signal was observed. Conclusions: B+P did not significantly improve median PFS or OS compared to TAS-102 in KRAS/NRAS mut mCRC. Subgroup analyses and translational studies are ongoing to determine which subgroups may be more likely to attain 4-mo PFS or identify mechanisms of resistance. Clinical trial information: NCT03981614.

Impact of local therapy on survival among patients with metastatic anal squamous cell carcinoma

4

Background: About 10-20% of patients with anal squamous cell carcinoma (SCCa) present with metastatic disease, and are usually treated with systemic chemotherapy. The role of local therapy to control the primary tumor is controversial in this setting. We evaluated survival impact of local therapy in metastatic anal SCCa. Methods: Data were obtained from all US hospitals that contributed to the National Cancer Database (NCDB) between 2004 and 2015. We excluded patients who did not receive palliative systemic chemotherapy. Univariate (UVA) and multivariable analyses (MVA) were performed to identify factors associated with patient outcome. Kaplan-Meier analysis and Cox proportional hazards models were used to assess the association between tumor/patient characteristics and overall survival (OS). Results: 1,160 patients were identified over 12 years. Median age was 57 years. Majority were female (64.9%), non-Hispanic Whites (79.1%) and had Charlson-Deyo Score of 0 (83.6%). Most common metastatic sites were liver (25.9%), lung (11.6%) and bone (8.5%). More than 79% of the patients received radiation to the primary site, and 10.4% underwent surgical resection for local control. Use of local therapy correlated closely with a significant improvement in OS on MVA (HR 0.66; 0.55-0.79; p < 0.001), with a 12-month and 5-year OS rates of 72.8% and 25.7% respectively, compared with 61.1% and 14.6% for patients treated with chemotherapy only. Poor prognostic factors included male gender (HR 1.44; 1.24-1.67; p < 0.001), age > 70 years (HR 1.28; 1.02-1.62; p = 0.034), lack of health insurance (HR 1.32; 1.02-1.71; p = 0.034), and cloacogenic zone location (HR 4.02; 1.43-11.30; p = 0.008). There was no benefit from abdominoperineal resection (mOS = 19.7mos; HR 1.05; 0.48-2.29; p = 0.909), but both local resection of the primary (mOS = 24.8mos, HR 0.48; 0.29-0.80; p = 0.005) and palliative radiation (mOS = 22.6 mos; HR 0.66; 0.55-0.79; p < 0.001) were associated with improved OS. Conclusions: This is the largest reported study on management of de novo stage IV SCCa. The data suggest that local control of the primary tumor through resection or radiation improved OS in patients with anal SCCa. Patients unlikely to benefit from local therapy include age over 70 years, male, lack of health insurance and cloacogenic carcinoma.

Phase Ib/II trial of siltuximab and spartalizumab in patients in metastatic pancreatic cancer

TPS626

Background: Interleukin-6 (IL-6) is associated with carcinogenesis, immune suppression, and poor prognosis in pancreatic adenocarcinoma (PDAC). Preclinical data demonstrated dual inhibition of IL-6 and (programmed death ligand-1) PD-L1 facilitates CD8+ T cell migration into pancreatic tumors and was effective in controlling tumor growth in syngeneic and genetically engineered PDAC mouse models. Siltuximab is a chimeric monoclonal antibody which targets the IL-6 molecule specifically and spartalizumab is a high-affinity ligand-blocking humanized IgG4 antibody against the PD-1 receptor. Based on this preclinical rationale, we developed a phase Ib/II trial to determine the recommended phase II dose (RP2D), evaluate the safety, toxicity profile, preliminary antitumor activity, and immunogenicity of the siltuximab and spartalizumab in patients with previously treated metastatic PDAC. Methods: The phase Ib trial design is standard 3+3. Primary endpoint is to determine RP2D. Siltuximab is administered intravenously (IV) in three dose levels of 6 mg/kg (DL1), 11 mg/kg (DL2), 9 mg/kg (only if 2 DLTs observed on DL2) every 3 weeks with spartalizumab at 300 mg IV every 3 weeks. Eligible patients must have stage IV PDAC who have failed at least one prior therapy age ≥18 years, ECOG PS 0-1, no prior anti PD-1 or anti-PD-L1 agent. After RP2D is established, an expansion phase will enroll 24 patients with PDAC. Pre and on-treatment biopsy will be performed in 24 patients in the expansion cohort for correlative analysis. Pre-treatment and on-treatment peripheral blood samples will be collected from all patients. In the expansion phase patients will receive initial cycle (every 3 weeks) treatment with either spartalizumab or spartalizumab plus siltuximab and then starting cycle 2 all patients receive the combination following the on-treatment research biopsy. This design will enable us to evaluate the immunological effects of spartalizumab alone versus the combination in the tumor microenvironment and peripheral blood. This study was activated in January 2020 and to date 12 patients were enrolled in dose escalation phase. The dose expansion phase has recently started accrual. Clinical trial information: NCT04191421.

Comparing Somatostatin Analogs in the Treatment of Advanced Gastroenteropancreatic Neuroendocrine Tumors

BACKGROUND

The 2 approved somatostatin analogs (SSAs) in the first-line treatment of advanced, well-differentiated gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are octreotide long-acting release (Sandostatin LAR) and somatuline depot (Lanreotide). The study's objective was to compare progression-free survival (PFS) and overall survival (OS) of patients (pts) with GEP-NETs treated with somatuline or octreotide LAR. Pts and Methods: Pts with advanced well-differentiated GEP-NET who received either SSA at Emory University between 1995 and 2019 were included after institutional review board approval. The primary end point was PFS, defined as time to disease progression (according to the Response Evaluation Criteria in Solid Tumors, version 1.1, or clinical progression) or death. The secondary end point was OS. Kaplan-Meier curves were generated, and log-rank tests were conducted to compare the survival outcomes.

RESULTS

A total of 105 pts were identified. The mean age was 62.1 years (SD ± 11.8). The male-to-female ratio was 51:54. The majority (N = 69, 65.7%) were white. Most pts had grade 2 (G2) disease (N = 44, 41.9%). Primary location was small bowel in 58 (55.2%), pancreas in 27 (25.7%), and other in 20 (19.0%). Functional tumors were defined in 32 pts distributed equally between the 2 groups. Distribution of treatment was similar in the 2 groups, with 54 receiving octreotide LAR and 51 receiving somatuline depot. The median PFS for the octreotide LAR and somatuline depot groups was 12 months (95% CI, 6-18 months) and 10.8 months (95% CI, 6-15.6 months), respectively, and the difference was not statistically significant (p = 0.2665). For pts with G1 disease, the median PFS for the octreotide LAR and somatuline depot was 8.4 versus 32.4 months, respectively, and the difference was not statistically significant (p = 0.159). For G2 disease, the difference in median PFS between octreotide LAR and somutaline depot groups was statistically significant (12 vs. 7.2 months, respectively; p = 0.0372). The mean follow-up time for octreotide LAR was 21.6 months versus 11.3 months for somatuline depot.

CONCLUSIONS

Overall, there was no difference in PFS between octreotide LAR and somatuline depot for pts with well-differentiated, metastatic GEP-NETs. A prospective study is worth designing selecting for G.

OUP accepted manuscript

Background

The survival impact of multi-agent (MAC) compared with single-agent (SAC) adjuvant chemotherapy (AC) in elderly patients with stage III colon cancer (CC) remains controversial. The aim of this study was to compare survival outcomes of MAC and SAC in this population utilizing the National Cancer Database (NCDB).

Patients and Methods

Patients aged ≥70 years with pathological stage III CC diagnosed in 2004-2015 were identified in the NCDB. Univariate and multivariable analyses were conducted, and Kaplan-Meier analysis and Cox proportional hazard models were used to identify associations between MAC vs. SAC and overall survival (OS).

Results

Among 41 707 elderly patients (≥70 years old) with stage III CC, about half (n = 20 257; 48.5%) received AC; the majority (n = 12 923, 63.8%) received MAC. The median age was 79 (range 70-90). The majority were female (n = 11 201, 55.3%), Caucasians (88%) and had moderately differentiated tumor grade (n = 12 619, 62.3%), tumor size >4 cm (11 785, 58.2%), and negative surgical margins (18 496, 91.3%). Low-risk stage III CC constituted 50.6% (n = 10 264) of the study population. High-risk stage III CC was associated with worse OS compared with low-risk disease (HR 0.35, 0.34-0.36, P < .001). Multi-agent chemotherapy was associated with a better 5-year OS compared with SAC (P < .001). High-risk stage III patients who received MAC vs. SAC had an OS of 4.2 vs. 3.4 years, respectively (P < .001). Low-risk stage III patients who received MAC vs. SAC had a median OS of 8.5 vs. 7 years (P < .001). In univariate and multivariable analyses, male sex, positive surgical margin, insurance and facility types, age, year of diagnosis, tumor size, and Charlson-Deyo score of >2 were associated with worse OS (P < .05).

Conclusions

Any adjuvant chemotherapy has a trend of survival benefits. Multi-agent chemotherapy seems to have an enhanced benefit in the 70-75 age group. Multi-agent chemotherapy seemed to have similar efficacy as SAC in those aged >76 years.

Predictive and Prognostic Effects of Primary Tumor Size on Colorectal Cancer Survival

Background

Pathologic staging is crucial in colorectal cancer (CRC). Unlike the majority of solid tumors, the current staging model does not use tumor size as a criterion. We evaluated the predictive and prognostic impact of primary tumor size on all stages of CRC.

Methods

Using the National Cancer Database (NCDB), we conducted an analysis of CRC patients diagnosed between 2010 and 2015 who underwent resection of their primary cancer. Univariate and multivariate analyses were used to identify predictive and prognostic factors, Kaplan-Meier analysis and Cox proportional hazards models for association between tumor size and survival.

Results

About 61,000 patients met the inclusion criteria. Median age was 63 years and majority of the tumors were colon primary (82.7%). AJCC stage distribution was: I - 20.1%; II - 32.1%; III - 34.7% and IV - 13.1%. The prognostic impact of tumor size was strongly associated with survival in stage III disease. Compared to patients with tumors <2cm; those with 2-5cm (HR 1.33; 1.19-1.49; p<0.001), 5-10cm (HR 1.51 (1.34-1.70; p<0.001) and >10cm (HR 1.95 (1.65-2.31; p<0.001) had worse survival independent of other variables. Stage II treated without adjuvant chemotherapy had comparable survival outcomes (HR 1.09; 0.97-1.523; p=0.148) with stage III patients who did, while Stage II patients who received adjuvant chemotherapy did much better than both groups (HR 0.76; 0.67-0.86; p<0.001). Stage III patients who did not receive adjuvant chemotherapy had the worst outcomes among the non-metastatic disease subgroups (HR 2.66; 2.48-2.86; p<0.001). Larger tumors were associated with advanced stage, MSI high, non-rectal primary and positive resection margins.

Conclusions

Further studies are needed to clarify the role of tumor size in prognostic staging models, and how to incorporate it into therapy decisions.

Role of Resection of the Primary in Metastatic Well-Differentiated Neuroendocrine Tumors

OBJECTIVE

Resection of the primary (RP) in metastatic neuroendocrine tumor (NET) is controversial. The aim was to evaluate survival outcomes for RP in metastatic NET patients.

METHODS

Data were obtained from US hospitals at the National Cancer Database between 2004 and 2014. χ2, analysis of variance tests, univariate, and multivariate cox proportional hazards models were evaluated. Kaplan-Meier curves and log-rank tests conducted to compare the survival difference of patient characteristics.

RESULTS

A total of 2361 patients were identified. The mean age was 62.1 years (standard deviation, 13 years), male-to-female ratio 1:1; 33% were small intestine, 26.3% pancreas, and 24.4% lung; 69.6% were well-differentiated; and 42.5% underwent RP. The 5-year overall survival (OS) was significantly improved for patients who underwent RP in small intestine (5-year OS, 63.9% vs 44.2%), lung (5-year OS, 65.4% vs 20.2%), and pancreas tumors (5-year OS, 75.6% vs 30.6%). On multivariate analysis, RP (hazard ratio, 0.46; 95% confidence interval, 0.29-0.73; P < 0.001), female, year of diagnosis 2010-2014, margin, Charlson-Deyo score less than 2, and age less than 51 years, were associated with better OS.

CONCLUSIONS

Resection of the primary in metastatic well-differentiated NET is associated with improved OS compared with no RP.

403 Correlative analysis of blood and biopsy samples from a clinical trial of Hsp90 inhibition in combination with pembrolizumab reveals increased intratumoral myeloid cell accumulation after treatment

Background

Pancreatic ductal adenocarcinoma (PDAC) has yet to widely benefit from T cell-targeted immunotherapy and displays universally poor prognosis. Thus, enhancing the activity of immunotherapy is a high priority. Our laboratory recently reported that heat shock protein-90 (Hsp90) inhibition enhances the efficacy of PD-1 blockade in murine models of PDAC (Zhang Y. et al., Mol Cancer Ther, 2020). Hsp90 inhibitors can limit activation of cancer associated fibroblasts (CAF) and promote infiltration of T cells when combined with PD-1 blockade in preclinical systems.

Methods

Based on these data, we are conducting a Phase Ib/II clinical trial to evaluate the combination of XL888 (Hsp90 inhibitor) and pembrolizumab in patients with metastatic pancreatic cancer. We hypothesize that this combination will be safe and elicit pronounced microenvironmental changes, leading to enhanced efficacy of checkpoint blockade in a tumor type that is otherwise refractory to this approach. During the phase II portion patients were randomized to receive a three week lead in with either pembrolizumab or pembrolizumab and XL888. Paired biopsies and blood samples were obtained at baseline and at week two on treatment and CyTOF was used to assess changes in circulating and tumor infiltrating immune populations. Further, CyTOF profiling of circulating immune cells was performed to assess impacts of XL888 on over thirty phenotypically defined immune populations (figure 1).

Results

As of June 2021, paired liver biopsy specimens from sites of metastasis have been successfully obtained from a total of 8 patients and paired peripheral blood mononuclear cell samples have been analyzed in 24 patients. Our CyTOF analysis illustrated a surprising increase in myeloid cell populations within the tumor following treatment. Analysis of circulating immune cells illustrated a decrease in natural killer cells and Th17 populations following treatment while naïve B cells were increased. These data will be validated by immunohistochemical analysis of FFPE biopsy specimens obtained in parallel at the time of CyTOF analysis. The impact of XL888 on systemic cytokines and chemokines (n=48 total) in the peripheral blood from patients enrolled in the clinical trial is therefore being assessed as a potential mechanism to explain this observation.

Abstract 403 Figure 1

Clinical trial and correlative analysis schema. Patients were randomized to receive either pembrolizumab alone or in combination with the HSP90 inhibitor XL888 for a two week cycle prior to crossover to the combination arm. Plasma, peripheral blood mononuclear cells (PBMC), and biopsies were assayed to evaluate immunomodulatory effects of the therapies.

Conclusions

Clinical data from this trial indicates that this combination is safe in patients. As clinical data matures, changes in soluble and cellular biomarkers will be correlated with response to elucidate mechanisms of response or resistance to this combination therapy.

Trial Registration

This clinical trial is underway and registered with the ID NCT03095781

Ethics Approval

The study was approved by Emory University’s Ethics Board, approval IRB00087397.

Consent

Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.

High-Risk Features Are Prognostic in dMMR/MSI-H Stage II Colon Cancer

BACKGROUND

High-risk features, such as T4 disease, bowel obstruction, poorly/undifferentiated histology, lymphovascular, perineural invasion, and <12 lymph nodes sampled, indicate poor prognosis and define high-risk stage II disease in proficient mismatch repair stage II colon cancer (CC). The prognostic role of high-risk features in dMMR/MSI-H stage II CC is unknown. Similarly, the role of adjuvant therapy in high-risk stage II CC with dMMR/MSI-H (≥1 high-risk feature) has not been studied in prospective trials. The aim of this analysis of the National Cancer Database is to evaluate the prognostic value of high-risk features in stage II dMMR/MSI-H CC.

METHODS

Univariate (UVA) and multivariate (MVA) Cox proportional hazards (Cox-PH) models were built to assess the association between clinical and demographic characteristics and overall survival. Kaplan-Meier survival curves were generated with log-rank tests to evaluate the association between adjuvant chemotherapy in high-risk and low-risk cohorts separately.

RESULTS

A total of 2,293 stage II CC patients have dMMR/MSI-H; of those, 29.5% (n = 676) had high-risk features. The high-risk dMMR/MSI-H patients had worse overall survival [5-year survival and 95%CI, 73.2% (67.3-78.1%) vs. 80.3% (76.7-83.5%), p = 0.0001]. In patients with stage II dMMR/MSI-H CC, the high-risk features were associated with shorter overall survival (OS) along with male sex, positive carcinoembryonic antigen, Charlson-Deyo score >1, and older age. Adjuvant chemotherapy administration was associated with better OS, regardless of the high-risk features in dMMR/MSI-H (log-rank test, p = 0.001) or not (p = 0.0006). When stratified by age, the benefit of chemotherapy was evident only in patients age ≥65 with high-risk features.

CONCLUSION

High-risk features are prognostic in the setting of dMMR/MSI-H stage II CC. Adjuvant chemotherapy may improve survival specifically in patients ≥65 years and with high-risk features.

Assessment of pegylated arginine deiminase and modified FOLFOX6 in patients with advanced hepatocellular carcinoma: Results of an international, single-arm, phase 2 study

BACKGROUND

Arginine starvation depletes the micronutrients required for DNA synthesis and interferes with both thymidylate synthetase activity and DNA repair pathways in preclinical models of hepatocellular carcinoma (HCC). Pegylated arginine deiminase (ADI-PEG 20), an arginine degrader, potentiates the cytotoxic activity of platinum and pyrimidine antimetabolites in HCC cellular and murine models.

METHODS

This was a global, multicenter, open-label, single-arm, phase 2 trial of ADI-PEG 20 and modified 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) in patients who had HCC with Child-Pugh A cirrhosis and disease progression on ≥2 prior lines of treatment. The primary objective was the objective response rate assessed according to Response Evaluation Criteria in Solid Tumors, version 1.1. Secondary objectives were to estimate progression-free survival, overall survival, safety, and tolerability. Eligible patients were treated with mFOLFOX6 intravenously biweekly at standard doses and ADI-PEG-20 intramuscularly weekly at 36 mg/m² .

RESULTS

In total, 140 patients with advanced HCC were enrolled. The median patient age was 62 years (range, 30-85 years), 83% of patients were male, 76% were of Asian race, 56% had hepatitis B viremia, 10% had hepatitis C viremia, 100% had received ≥2 prior lines of systemic therapy, and 39% had received ≥3 prior lines of systemic therapy. The objective response rate was 9.3% (95% confidence interval [CI], 5.0%-15.4%), with a median response duration of 10.2 months (95% CI, 5.8 months to not reached). The median progression-free survival was 3.8 months (95% CI, 1.8-6.3 months), and the median overall survival was 14.5 months (95% CI, 13.6-20.9 months). The most common grade ≥3 treatment-related events were neutropenia (32.9%), white blood cell count decrease (20%), platelet count decrease (19.3%), and anemia (9.3%).

CONCLUSIONS

Concurrent mFOLFOX6 plus ADI-PEG 20 exhibited limited antitumor activity in patients with treatment-refractory HCC. The study was terminated early, and no further evaluation of the combination will be pursued.

LAY SUMMARY

Arginine is an important nutrient for hepatocellular carcinoma (HCC). The depletion of arginine with pegylated arginine deiminase (ADI-PEG 20), an arginine degrader, appeared to make chemotherapy (FOLFOX) work better in animal models of HCC and in patients with HCC on an early phase clinical trial. To formally test this hypothesis in the clinical setting, a large, global, phase 2 clinical trial was conducted of ADI-PEG 20 and FOLFOX in the treatment of patients with refractory HCC. The study showed limited activity of ADI-PEG 20 and FOLFOX in advanced HCC and was stopped early.

Pharmacokinetics and safety of niraparib in patients with moderate hepatic impairment

PURPOSE

The purpose of this study is to characterize niraparib pharmacokinetics (PK) and safety in patients with normal hepatic function (NHF) versus moderate hepatic impairment (MHI).

METHODS

Patients with advanced solid tumors were stratified by NHF or MHI (National Cancer Institute-Organ Dysfunction Working Group criteria [bilirubin > 1.5-3 × upper limit of normal and any aspartate aminotransferase elevation]). In the PK phase, all patients received one 300 mg dose of niraparib. In the extension phase, patients with MHI received niraparib 200 mg daily; patients with NHF received 200 or 300 mg based on weight (< 77 kg, ≥ 77 kg)/platelets (< 150,000/µL, ≥ 150,000/µL). PK parameters included maximum concentration (C_max), area under the curve to last measured concentration (AUC_last) and extrapolated to infinity (AUC_inf). Safety was assessed in both phases. Exposure-response (E-R) modeling was used to predict MHI effects on exposure and safety of niraparib doses ≤ 200 mg or 300/200 mg or 200/100 mg weight/platelet regimens.

RESULTS

In the PK phase (NHF, n = 9; MHI, n = 8), mean niraparib C_max was 7% lower in patients with MHI versus NHF. Mean exposure (AUC_last, AUC_inf) was increased by 45% and 56%, respectively, in patients with MHI without impacting tolerability. In the extension phase (NHF, n = 8; MHI, n = 7), the overall safety profile was consistent with previous trials. In patients with MHI, E-R modeling predicted niraparib 200 mg reduced Grade ≥ 3 thrombocytopenia incidence, whereas a 200/100 mg regimen yielded exposures below efficacy-associated levels in 15% of patients.

CONCLUSION

These findings support adjusting the 300 mg niraparib starting dose to 200 mg QD in patients with MHI.

TRIAL REGISTRATION

NCT03359850; registered December 2, 2017.

Improved Tumor Response in Patients on Metformin Undergoing Yttrium-90 Radioembolization Segmentectomy for Hepatocellular Carcinoma

PURPOSE

Metformin is associated with improved outcomes after external radiation and chemotherapy but has not been studied for Y-90 radiation segmentectomy (RS). This study evaluates the effect of metformin on tumor response after Y-90 RS in patients with hepatocellular carcinoma (HCC).

METHODS AND MATERIALS

A retrospective analysis of patients with HCC who underwent Y-90 RS between 2014-2018 was performed. Comparisons were made between all patients taking and not taking metformin, and diabetic patients taking and not taking metformin. Tumor response was analyzed with logistic regression to compare absolute and percent change in total tumor diameter (TTD) and modified Response Evaluation Criteria in Solid Tumors (mRECIST). Overall survival (OS) was evaluated using Kaplan-Meier estimation and log-rank analysis.

RESULTS

A total of 106 patients underwent 112 Y-90 RS, of which 40 were diabetic (38.8%) and 19 (18.4%) were on metformin. At baseline, the two groups of patients on metformin and not on metformin had no significant difference in age, Child-Pugh score, MELD score, ALBI grade, total tumor diameter, and size of dominant tumor. The only significant baseline difference was ECOG status. Uni- and multivariate analysis demonstrated a larger reduction in TTD and objective response by mRECIST criteria for patients undergoing Y-90 RS on metformin compared to those not on metformin. OS was similar between patients taking and not taking metformin (p = 0.912).

CONCLUSION

Metformin may be associated with increased tumor response after Y-90 RS in patients with HCC.

LEVEL OF EVIDENCE

III, Retrospective Study.

Clinical features and outcomes of colloid carcinoma of pancreas compared to pancreatic ductal adenocarcinoma

e16259

Background: Colloid carcinoma (CC) of the pancreas is a rare histopathological subtype of ductal adenocarcinoma (PDAC), with poorly defined prognostic factors and therapeutic outcomes. The aim of this study is to characterize the clinicopathological features and evaluate the overall survival (OS) and prognostic factors of patients with pancreatic CC using National Cancer Database (NCDB). Methods: Patients diagnosed with CC of the pancreas and PDAC between 2004 and 2016 were identified from the NCDB using ICD-O-3 morphology (8480/3 for CC and 8140/3 for PDAC) and topography codes (C25). Univariate and multivariable analyses were conducted and Kaplan-Meier analysis and Cox proportional hazards models were used to perform OS analysis. Results: A total of 56,846 patients met the inclusion criteria for the final analysis. Of the total population included, 2,430 patients (4.3%) had CC and 54,416 patients (95.7%) had PDAC. For both, CC and PDAC, there was a male preponderance (52.0%, 52.5%), Caucasians (85.1%, 84%), occurrence above the age of 70 (39.2%, 38.2%), and the most common primary site was the head of the pancreas (50.5%, 53%). For CC, the percentage of pathologic stage III colloid pancreas cancer appeared the lowest (3.5%, 85 patients), compared to stage I (16.7%), stage II (37.8%), and stage IV (42.1%). While in PDAC, the percentage of pathologic stage I (5.94%) and stage III (4.44%) patients was lower than stage II (37.21%) and IV (52.41%). CC and PDAC more frequently presented with < 5cm tumor, at academic or research cancer centers, and diagnosed between 2009 and 2013 compared to 2004–2008 ( p< 0.001). For both CC and PDAC, the majority underwent surgical resection (58%, 53%), systemic chemotherapy (57.8%, 63%) and did not receive radiotherapy (78.8%, 77.6%). A positive surgical margin on pathologic evaluation was associated with worse outcomes for CC and PDAC in both univariate and multivariate analysis (HR 1.61; 1.56–1.66; p< 0.001 and HR 1.43; 1.38–1.48, p< 0.001). CC had a better 1-year overall survival (OS) in all stages compared to PDAC (p < 0.001). In multivariate analysis, mucinous carcinoma histology, female sex, diagnosis between 2004 and 2009, well/moderately differentiated histology, chemotherapy, age at diagnosis less than 60, radiation therapy after surgery, and local surgical procedure of primary site and pancreatectomy (p < 0.001) were associated with better OS compared to PDAC. Colloid histology was associated with better 1-year overall survival (OS) in all stages compared to PDAC (p < 0.001). Conclusions: Colloid carcinoma of pancreas is associated with a better overall survival as compared to pancreatic ductal adenocarcinoma. This is the largest study to address the clinical features and outcomes of colloid carcinoma of pancreas.

Treatment outcomes for stage T1b-2 esophagogastric adenocarcinomas

e16085

Background: Treatment of localized esophageal, gastroesophageal junction (GEJ), and stomach cancer is neoadjuvant therapy with either chemoradiation or chemotherapy followed by surgery. Treatment for T1b-2 stage disease is not well evaluated and this stage is underrepresented in prospective studies. The aim of this study is to evaluate survival outcomes among the three treatment modalities (neoadjuvant chemotherapy (NACT), neoadjuvant chemoradiation (NACRT), and upfront surgery (US)) in this population using the National Cancer Database (NCDB). Methods: Patients (pts) with clinical stage T1b-2N0 and any pathological stage (excluding metastatic) adenocarcinoma of the esophagus, GEJ, and stomach treated with neoadjuvant therapy or upfront surgery, with or without adjuvant chemotherapy (AC), were identified between 2004 and 2015 in the NCDB. Univariate and multivariable analyses were conducted, and Kaplan-Meier analysis and Cox proportional hazard models were used to identify the association between the three treatment modalities and overall survival (OS). Results: A total of 2260 pts were analyzed. The median follow-up was 66.6 months. The median age was 67 years. Most pts were White (86%) and male (77%). 1018 (45%) had moderately-differentiated grade, while 946 (42%) had poorly-differentiated/undifferentiated grade. The most common site of disease was the lower third of esophagus (34.1%). 161 pts (7%) received NACT, of whom 45 pts received AC; 537 pts (24%) received NACRT, of whom 40 pts received AC. 1562 pts (69%) underwent US, of whom 146 pts received AC. US with AC was associated with the best survival, followed by NACT with AC; median OS was 90.1 and 86.8 months for surgery with AC and NACT with AC, respectively. NACRT was associated with the worst survival (39.5 and 40.2 months with and without AC, respectively). The 5-year OS rates were 59.8%, 58.5%, 52.1%, 44.9%, 37.3%, and 37.8%, for US, NACT, and NACRT, with and without AC, respectively. The rate of tumor upstaging was highest in the NACT group, followed by the NACRT group, and lowest in the US group. Postsurgically, 62 (39%) and 48 (30%) pts in the NACT group and 198 (37%) and 161 (30%) pts in the NACRT group had upstaging in their T and N stages, respectively, compared to 214 (13%) and 326 (21%) pts in the US group. For the 1107 pts who also had pathological T1b-2N0 stage disease following US, no difference in survival was observed with or without AC. Conclusions: Upfront surgery with adjuvant chemotherapy and perioperative chemotherapy are associated with the best survival compared to preoperative radiotherapy. This is the largest study to address the best approach for the treatment of T1b-2 stage disease.

Survival Outcomes of Acinar Cell Pancreatic Cancer: A National Cancer Database Analysis

OBJECTIVES

Acinar cell pancreatic carcinomas (ACPCs) are rare neoplasms accounting for 1% to 2% of pancreatic tumors in adults. The objective of this study is to evaluate the benefit of chemotherapy in the adjuvant setting in resected ACPC and in the palliative setting for metastatic ACPC.

METHODS

Data were obtained from all US hospitals that contributed to the National Cancer Database between 2004 and 2014. Cases were identified using the histology code 8550.

RESULTS

A total of 593 patients with ACPC were identified. The mean age was 64.4 years (range, 18-90 years), with a male preponderance (72.8%, n = 432). Localized stage disease comprised 52.3% (n = 310) of patients. Among localized ACPC patients, 88.0% (n = 191) underwent surgery and 50.6% (n = 91) received adjuvant chemotherapy. The 5-year overall survival in those who received adjuvant treatment was slightly higher than those who did not receive adjuvant treatment (46.7% vs 44.8%, P = 0.3271). Among advanced-stage ACPC patients, 67.6% received chemotherapy, which translated into improved 5-year overall survival compared with no chemotherapy (8.1% vs 0%, P < 0.0001).

CONCLUSIONS

Chemotherapy in the palliative setting for advanced-stage ACPC patients was associated with improved survival. Adjuvant therapy did not translate into significant survival benefit.

Impact of Tumor Side on Clinical Outcomes in Stage II and III Colon Cancer With Known Microsatellite Instability Status

Background

Tumor sidedness as a prognostic factor in advanced stage colon cancer (CC) is well established. The impact of tumor sidedness on the clinical outcomes of stage II and III CC has not been well studied.

Methods

The National Cancer Database (NCDB) was utilized to identify patients with pathological stage II and III primary adenocarcinoma of the colon from 2010 to 2015 using ICD-O-3 morphology and topography codes: 8140-47, 8210-11, 8220-21, 8260-63, 8480-81, 8490 and C18.0, 18.2,18.3, 18.5,18.6, 18.7. Univariate (UVA) and multivariable (MVA) survival analyses and Kaplan–Meier Curves with Log-rank test were utilized to compare overall survival (OS) based on tumor location and treatment received.

Results

A total of 35,071 patients with stage II (n = 17,629) and III (n = 17,442) CC were identified. 51.3% female; 81.5% Caucasian; median age 66 (range, 18–90). Majority of stage II and III tumors were right sided, 61.2% (n = 10,794) and 56.0% (n = 9,763). Microsatellite instability high (MSI-H) was more common in stage II compared to III, 23.3% (n = 4,115) vs 18.2% (n = 3,171) (p < 0.0001). In stage II MSI-H CC right was more common than left, 78.3% (n = 3223) vs 21.7% (n = 892). There was no significant difference in survival between stage II MSI-H left vs right (5-year OS 76.2 vs 74.7%, p = 0.1578). Stage II MSS CC right was more common than left, 56.0% (n = 7571) vs 44.0% (n = 5943), and survival was better in the left vs right (5-year OS 73.2 vs 70.8%, p = 0.0029). Stage III MSI-H CC was more common in the right than in the left, 75.6% (n = 2,397) vs 24.4% (n = 774) and survival was better in the left (5-year OS 62.5 vs 56.5%, p = 0.0026). Stage III MSS CC was more common in the right than in the left, 51.6% (n = 7,366) vs 48.4% (n = 6,905), and survival was better in the left vs right (5-year OS 67.0 vs 54.4%, p < 0.001).

Conclusion

Survival was better in left sided tumors compared to right in stage II MSS, stage III MSS, and stage III MSI-H CC.

Impact of Sarcopenia, BMI, and Inflammatory Biomarkers on Survival in Advanced Hepatocellular Carcinoma Treated With Anti-PD-1 Antibody

BACKGROUND

Sarcopenia and inflammation are independently associated with worse survival in cancer patients. This study aims to determine the impact of sarcopenia, body mass index (BMI), and inflammatory biomarkers on survival in advanced hepatocellular carcinoma (HCC) patients treated with anti-PD-1 antibody-based immunotherapy.

METHODS

A retrospective review of advanced HCC patients treated with immunotherapy at Winship Cancer Institute between 2015 and 2019 was performed. Baseline computed tomography and magnetic resonance images were collected at mid-L3 level, assessed for skeletal muscle density using SliceOmatic (TomoVision, version 5.0) and converted to skeletal muscle index (SMI) by dividing it by height (m2). Sex-specific sarcopenia was defined by the median value of SMI. The optimal cut for continuous inflammation biomarker was determined by bias-adjusted log-rank test. Overall survival (OS) was set as primary outcome and Cox proportional hazard model was used for association with survival.

RESULTS

A total of 57 patients were included; 77.2% male, 52.6% Caucasian, 58.5% Eastern Cooperative Oncology Group performance status 0-1, 80.7% Child Pugh A. Treatment was second line and beyond in 71.9% of patients. The median follow-up time was 6 months. Sarcopenia cut-off for males and females was SMI of 43 and 39, respectively. 49.1% of patients had sarcopenia. Median OS was 5 versus 14.3 months in sarcopenic versus nonsarcopenic patients (Log-rank P=0.054). Median OS was 5 and 17.5 months in patients with BMI <25 and BMI ≥25, respectively (Log-rank P=0.034). Median OS was 3.6 and 14.3 months for patients with neutrophil-to-lymphocyte ratio (NLR) ≥5.15 versus NLR <5.15 (Log-rank P<0.001). In multivariable Cox regression model, higher baseline NLR was associated with worse OS (hazard ratio [HR]: 4.17, 95% confidence interval [CI]: 1.52-11.39, P=0.005). Sex-specific sarcopenia showed a trend of worse OS (HR: 1.71, 95% CI: 0.73-4.00, P=0.215) but was not statistically significant. BMI<25 was associated with worse OS (HR: 2.28, 95% CI: 0.92-5.65, P=0.076). In the association with progression free survival, neither baseline BMI nor sex-specific sarcopenia showed statistical significance.

CONCLUSION

After controlling for baseline Child Pugh score and NLR, sex-specific sarcopenia does not predict OS. Baseline BMI and NLR together may predict OS in advanced HCC patients treated with anti-PD-1 antibody.

Survival analysis of colorectal cancer patients treated with first-line modified FOLFOX6 with or without bolus fluorouracil

35

Background: The combination of oxaliplatin, bolus 5-FU (b5FU), infusional 5-FU (5-FUCI), and leucovorin (LV) is the preferred first line treatment option for mCRC. This study evaluates the impact of b5FU on survival in first line therapy for mCRC patients treated with mFOLFOX6. Methods: This was a retrospective chart review of patients ≥ 18 years old with mCRC receiving palliative first line mFOLFOX6 chemotherapy with or without b5FU/ LV from January 1, 2010 through June 1, 2019 at Winship Cancer Institute, Emory University. Data collection included the following: demographics (age, race, gender), disease characteristics (tumor sidedness), microsatellite status, KRAS status, BRAF status, addition of monoclonal antibodies (bevacizumab, panitumumab), ECOG PS, grade 3/4 neutropenic events, addition of growth factors, and treatment delays. The primary endpoint was PFS. The multivariable Cox proportional hazards model for PFS and OS was performed with selected covariates of interest. Results: A total of 252 patients with mCRC met the inclusion criteria. Median follow-up time was 2.4 years. 161 patients (64%) received mFOLFOX6 with b5FU/LV and 91 patients (36%) received mFOLFOX6 with no b5FU/LV. More cycles were delivered in the b5FU group as compared to the non-b5FU group (mean, 4.8 v. 3.8 cycles, respectively; p < 0.001). There were no differences in grade 3 and 4 neutropenic events between groups. Growth factor usage was numerically higher in the bolus group though not significantly different (p = 0.06). No difference was observed in treatment delays between groups (p = 0.83). There was no statistical difference in PFS between treatment groups (1.1 years in the b5FU/LV group v. 0.8 years (95% CI, 0.6-1.0) in the no 5-FU/LV bolus group; p = 0.076). The median OS was 2.5 years in the b5FU/LV group compared to 1.8 years in the no b5FU/LV group (p = 0.012). On univariate analysis, tumor sidedness and performance status were significantly different between groups. On multivariate analysis, none of the variables were significantly different between groups. Conclusions: The omission of the b5FU/LV from mFOLFOX6 does not significantly impact PFS, toxicity or treatment delays. However, OS is significantly shorter when the b5FU/LV is omitted suggesting the clinical importance of maintaining bolus administration with 5-FUCI in the first line palliative treatment of mCRC.

Survival outcomes of adjuvant chemotherapy in elderly patients with stage III colon cancer

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Background: The survival impact of multi-agent (MAC) as compared to single-agent (SAC) adjuvant chemotherapy (AC) in elderly patients with stage III colon cancer (CC) remains controversial. The aim of this study is to evaluate the survival outcome comparing MAC to SAC in this population utilizing the National Cancer DataBase (NCDB). Methods: Patients 70 years and older with pathological stage III CC were identified between 2004 and 2015 from the NCDB using ICD-O-3 morphology and topography codes: 8140-47, 8210-11, 8220-21, 8260-63, 8480-81, 8490, and C18.0-18.8 (without C18.1). Univariate and multivariable analyses were conducted and Kaplan-Meier analysis and Cox proportional hazard models were used to identify the association between MAC vs. SAC and overall survival (OS). Results: A total of 41,707 elderly patients (≥70 years old) with stage III CC were identified. Around half of the patients (n = 20,257; 48.5%) received AC; the majority of whom (n = 12,923, 63.8%) received MAC. The median age was 79 (range 70-90). Of the patients who received AC, the majority were female (n = 11,201, 55.3 %), Caucasians (87.4%) and had a moderately differentiated tumor grade (n = 12,619, 62.3%). Tumor size more than 4 cm was identified in 11,785 (58.2%) patients and 18,496 (91.3%) had negative surgical margins. Low-risk stage III CC constituted 50.6% (n = 10,264) of the study population. High-risk stage III CC was associated with worse OS compared to low-risk disease (p < 0.001). MAC was associated with better 5-year OS compared to SAC (p < 0.001). High-risk stage III patients who received MAC had an OS of 4.2 v. 3.4 years in SAC (p < 0.001). In low risk stage III, patients who received MAC had median OS of 8.5 v. 7 years in SAC (p < 0.001). In Univariate, male sex, positive surgical margin, insurance and facility types, age, year of diagnosistumor size, and Charlson-Deyo Score of > 2 were associated with worse OS (p < 0.05). Conclusions: Multi-agent AC is associated with better survival in stage III CC patients 70 years and older compared to SAC. Enhanced benefit of MAC was shown for both low risk and high risk stage III CC.

Phase II trial of nivolumab and metformin in patients with treatment refractory microsatellite stable metastatic colorectal cancer

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Background: Preclinical data suggests metformin can improve immune exhaustion of tumor infiltrating lymphocytes and potentiate the effects of PD-1 blockade. By normalizing the hypoxic TME, metformin was shown to improve cytotoxic T cell function and efficacy of anti-PD-1 antibody in highly aggressive B16 melanoma and MC38 colon adenocarcinoma tumor models. Based on this preclinical rationale we conducted a phase II study with nivolumab and metformin combination in treatment refractory MSS metastatic colorectal cancer (mCRC). Methods: Nivolumab 480 mg IV every 4 weeks and Metformin 1000 mg po twice daily was administered in 28-day cycles following a 14-day metformin only lead-in phase.Eligible patients included stage IV metastatic treatment refractory MSS mCRC (patients must have received oxaliplatin, irinotecan, and fluoropyrimidine), age ≥18 years, ECOG PS 0-1, adequate organ function, no prior anti PD-1 agent. The primary endpoint was overall response rate (ORR). Secondary endpoints included overall survival (OS) and progression free survival (PFS). Simon’s two-stage Minimax design was employed (H0: ORR =4%; H1: ORR=15%; alpha = 0.1; power =80%). If ≥1 objective response was observed in the first evaluable 18 patients, 10 additional patients would be included in the cohort. ≥3 objective responders in 28 patients would be required to be considered positive study. Pre-treatment and on-treatment research biopsies and correlative peripheral blood specimens were collected. Results: A total of 24 patients were enrolled, 6 patients were replaced per protocol, and 18 patients had evaluable disease. Of the 18 evaluable patients 11/18 (61%) were female, median age 58 [IQR 50-67]. 2 patients had prolonged stable disease (4 and 10 cycles). No patients had objective response based on RECIST 1.1. Median OS and PFS was 5.1 months [95% CI (2-11.7)] and 2.3 months [95% CI (1.7-2.4)], respectively. Most common grade 3 and 4 toxicities were anemia (n=2) and diarrhea (n=2). Conclusions: In treatment refractory MSS mCRCnivolumab and metformin combination was well tolerated. Two patients achieved stable disease, but no objective response was seen; therefore, the study did not proceed with the second stage of enrollment. Immunologic correlative analysis of this study is ongoing. Clinical trial information: NCT03800602.