Next-generation therapies for pancreatic cancer

INTRODUCTION

Pancreas ductal adenocarcinoma (PDAC) is a frequently lethal malignancy that poses unique therapeutic challenges. The current mainstay of therapy for metastatic PDAC (mPDAC) is cytotoxic chemotherapy. NALIRIFOX (liposomal irinotecan, fluorouracil, leucovorin, oxaliplatin) is an emerging standard of care in the metastatic setting. An evolving understanding of PDAC pathogenesis is driving a shift toward targeted therapy. Olaparib, a poly-ADP-ribose polymerase (PARP) inhibitor, has regulatory approval for maintenance therapy in BRCA-mutated mPDAC along with other targeted agents receiving disease-agnostic approvals including for PDAC with rare fusions and mismatch repair deficiency. Ongoing research continues to identify and evaluate an expanding array of targeted therapies for PDAC.

AREAS COVERED

This review provides a brief overview of standard therapies for PDAC and an emphasis on current and emerging targeted therapies.

EXPERT OPINION

There is notable potential for targeted therapies for KRAS-mutated PDAC with opportunity for meaningful benefit for a sizable portion of patients with this disease. Further, emerging approaches are focused on novel immune, tumor microenvironment, and synthetic lethality strategies.

Physical activity in recurrent colon cancer: Cancer and Leukemia Group B/SWOG 80702 (Alliance)

BACKGROUND

One in three patients with stage III colon cancer will experience tumor recurrence. It is uncertain whether physical activity during and after postoperative chemotherapy for stage III colon cancer improves overall survival after tumor recurrence.

METHODS

A prospective cohort study nested within a randomized multicenter trial of patients initially diagnosed with stage III colon cancer who experienced tumor recurrence (N = 399) was conducted. Postoperative physical activity before tumor recurrence was measured. Physical activity energy expenditure was quantified via metabolic equivalent task hours per week (MET-h/week). The primary end point was overall survival after tumor recurrence. Multivariable flexible parametric survival models estimated relative and absolute effects with two-sided hypothesis tests.

RESULTS

Compared with patients expending <3.0 MET-h/week of physical activity (comparable to <1.0 h/week of brisk walking), patients with ≥18.0 MET-h/week of physical activity (comparable to 6 h/week of brisk walking) had a 33% relative improvement in overall survival time after tumor recurrence (hazard ratio, 0.67; 95% CI, 0.42-0.96). The overall survival rate at 3 years after tumor recurrence was 61.3% (95% CI, 51.8%-69.2%) with <3.0 MET-h/week of physical activity and 72.2% (95% CI, 63.1%-79.6%) with ≥18 MET-h/week of physical activity (risk difference, 10.9 percentage points; 95% CI, 1.2-20.8 percentage points).

CONCLUSIONS

Higher postoperative physical activity is associated with improved overall survival after tumor recurrence in patients initially diagnosed with stage III colon cancer. These data may be relevant to patients who, despite optimal postoperative medical therapy, have a high risk of tumor recurrence.

Timing of Initiation of Palliative Chemotherapy in Asymptomatic Patients with Metastatic Pancreatic Cancer: An International Expert Survey and Case-Vignette Study

Background: The use of imaging, in general, and during follow-up after resection of pancreatic cancer, is increasing. Consequently, the number of asymptomatic patients diagnosed with metastatic pancreatic cancer (mPDAC) is increasing. In these patients, palliative systemic therapy is the only tumor-directed treatment option; hence, it is often immediately initiated. However, delaying therapy in asymptomatic palliative patients may preserve quality of life and avoid therapy-related toxicity, but the impact on survival is unknown. This study aimed to gain insight into the current perspectives and clinical decision=making of experts regarding the timing of treatment initiation of patients with asymptomatic mPDAC. Methods: An online survey (13 questions, 9 case-vignettes) was sent to all first and last authors of published clinical trials on mPDAC over the past 10 years and medical oncologists of the Dutch Pancreatic Cancer Group. Inter-rater variability was determined using the Kappa Light test. Differences in the preferred timing of treatment initiation among countries, continents, and years of experience were analyzed using Fisher's exact test. Results: Overall, 78 of 291 (27%) medical oncologists from 15 countries responded (62% from Europe, 23% from North America, and 15% from Asia-Pacific). The majority of respondents (63%) preferred the immediate initiation of chemotherapy following diagnosis. In 3/9 case-vignettes, delayed treatment was favored in specific clinical contexts (i.e., patient with only one small lung metastasis, significant comorbidities, and higher age). A significant degree of inter-rater variability was present within 7/9 case-vignettes. The recommended timing of treatment initiation differed between continents for 2/9 case-vignettes (22%), in 7/9 (77.9%) comparing the Netherlands with other countries, and based on years of experience for 5/9 (56%). Conclusions: Although the response rate was limited, in asymptomatic patients with mPDAC, immediate treatment is most often preferred. Delaying treatment until symptoms occur is considered in patients with limited metastatic disease, more comorbidities, and higher age.

Metastatic well differentiated serotonin-producing pancreatic neuroendocrine tumor with carcinoid heart disease: a case report

Background

Less than two percent of pancreatic neuroendocrine tumors (NETs) produce serotonin. Serotonin can cause carcinoid syndrome and less commonly carcinoid heart disease (CHD). CHD is associated with increased mortality and requires a more aggressive approach. Here we present a rare case of a serotonin-producing pancreatic NET complicated by CHD at presentation and discuss timing of systemic therapy, liver-directed therapy, and heart failure management.

Case Description

A 36-year-old white man presented with diarrhea, lower extremity edema, and exertional dyspnea. He was found to have a well-differentiated serotonin-producing pancreatic NETs grade three with bilobar liver metastasis complicated by carcinoid syndrome and CHD. His symptoms and disease burden improved with somatostatin analog and liver-directed therapy with bland embolization to control carcinoid symptoms and obtain rapid hormonal control to prevent progression of CHD. He concurrently received diuretics to manage his heart failure and was considered for valvular replacement surgery, which was deferred for optimal hormonal control.

Conclusions

Our case highlights the importance of multidisciplinary care for patients with pancreatic NETs and early identification and management of CHD. Although uncommon, serotonin-producing pancreatic NETs can present with CHD and require combination of somatostatin analogs, liver-directed therapy, and heart failure management.

Plasma 25-Hydroxyvitamin D Levels and Survival in Stage III Colon Cancer: Findings from CALGB/SWOG 80702 (Alliance)

PURPOSE

To assess whether higher plasma 25-hydroxyvitamin D [25(OH)D] is associated with improved outcomes in colon cancer and whether circulating inflammatory cytokines mediate such association.

EXPERIMENTAL DESIGN

Plasma samples were collected from 1,437 patients with stage III colon cancer enrolled in a phase III randomized clinical trial (CALGB/SWOG 80702) from 2010 to 2015, who were followed until 2020. Cox regressions were used to examine associations between plasma 25(OH)D and disease-free survival (DFS), overall survival (OS), and time to recurrence (TTR). Mediation analysis was performed for circulating inflammatory biomarkers of C-reactive protein (CRP), IL6, and soluble TNF receptor 2 (sTNF-R2).

RESULTS

Vitamin D deficiency [25(OH)D <12 ng/mL] was present in 13% of total patients at baseline and in 32% of Black patients. Compared with deficiency, nondeficient vitamin D status (≥12 ng/mL) was significantly associated with improved DFS, OS, and TTR (all Plog-rank<0.05), with multivariable-adjusted HRs of 0.68 (95% confidence interval, 0.51-0.92) for DFS, 0.57 (0.40-0.80) for OS, and 0.71 (0.52-0.98) for TTR. A U-shaped dose-response pattern was observed for DFS and OS (both Pnonlinearity<0.05). The proportion of the association with survival that was mediated by sTNF-R2 was 10.6% (Pmediation = 0.04) for DFS and 11.8% (Pmediation = 0.05) for OS, whereas CRP and IL6 were not shown to be mediators. Plasma 25(OH)D was not associated with the occurrence of ≥ grade 2 adverse events.

CONCLUSIONS

Nondeficient vitamin D is associated with improved outcomes in patients with stage III colon cancer, largely independent of circulation inflammations. A randomized trial is warranted to elucidate whether adjuvant vitamin D supplementation improves patient outcomes.

Atezolizumab Plus PEGPH20 Versus Chemotherapy in Advanced Pancreatic Ductal Adenocarcinoma and Gastric Cancer: MORPHEUS Phase Ib/II Umbrella Randomized Study Platform

BACKGROUND

The MORPHEUS platform comprises multiple open-label, randomized, phase Ib/II trials designed to identify early efficacy and safety signals of treatment combinations across cancers. Atezolizumab (anti-programmed cell death 1 ligand 1 [PD-L1]) was evaluated in combination with PEGylated recombinant human hyaluronidase (PEGPH20).

METHODS

In 2 randomized MORPHEUS trials, eligible patients with advanced, previously treated pancreatic ductal adenocarcinoma (PDAC) or gastric cancer (GC) received atezolizumab plus PEGPH20, or control treatment (mFOLFOX6 or gemcitabine plus nab-paclitaxel [MORPHEUS-PDAC]; ramucirumab plus paclitaxel [MORPHEUS-GC]). Primary endpoints were objective response rates (ORR) per RECIST 1.1 and safety.

RESULTS

In MORPHEUS-PDAC, ORRs with atezolizumab plus PEGPH20 (n = 66) were 6.1% (95% CI, 1.68%-14.80%) vs. 2.4% (95% CI, 0.06%-12.57%) with chemotherapy (n = 42). In the respective arms, 65.2% and 61.9% had grade 3/4 adverse events (AEs); 4.5% and 2.4% had grade 5 AEs. In MORPHEUS-GC, confirmed ORRs with atezolizumab plus PEGPH20 (n = 13) were 0% (95% CI, 0%-24.7%) vs. 16.7% (95% CI, 2.1%-48.4%) with control (n = 12). Grade 3/4 AEs occurred in 30.8% and 75.0% of patients, respectively; no grade 5 AEs occurred.

CONCLUSION

Atezolizumab plus PEGPH20 showed limited clinical activity in patients with PDAC and none in patients with GC. The safety of atezolizumab plus PEGPH20 was consistent with each agent's known safety profile. (ClinicalTrials.gov Identifier: NCT03193190 and NCT03281369).

Pancreatic Cancer: BRCA Targeted Therapy and Beyond

Pancreatic ductal adenocarcinoma (PDAC) is projected to become the second leading cause of cancer-related death in the US by 2030, despite accounting for only 5% of all cancer diagnoses. Germline gBRCA1/2-mutated PDAC represents a key subgroup with a favorable prognosis, due at least in part to additional approved and guideline-endorsed therapeutic options compared with an unselected PDAC cohort. The relatively recent incorporation of PARP inhibition into the treatment paradigm for such patients has resulted in renewed optimism for a biomarker-based approach to the management of this disease. However, gBRCA1/2 represents a small subgroup of patients with PDAC, and efforts to extend the indication for PARPi beyond BRCA1/2 mutations to patients with PDAC and other genomic alterations associated with deficient DNA damage repair (DDR) are ongoing, with several clinical trials underway. In addition, despite an array of approved therapeutic options for patients with BRCA1/2-associated PDAC, both primary and acquired resistance to platinum-based chemotherapies and PARPi presents a significant challenge in improving long-term outcomes. Herein, we review the current treatment landscape of PDAC for patients with BRCA1/2 and other DDR gene mutations, experimental approaches under investigation or in development, and future directions.

Registration-based biomarkers for neoadjuvant treatment response of pancreatic cancer via longitudinal image registration

Purpose

Pancreatic ductal adenocarcinoma (PDAC) frequently presents as hypo- or iso-dense masses with poor contrast delineation from surrounding parenchyma, which decreases reproducibility of manual dimensional measurements obtained during conventional radiographic assessment of treatment response. Longitudinal registration between pre- and post-treatment images may produce imaging biomarkers that more reliably quantify treatment response across serial imaging.

Approach

Thirty patients who prospectively underwent a neoadjuvant chemotherapy regimen as part of a clinical trial were retrospectively analyzed in this study. Two image registration methods were applied to quantitatively assess longitudinal changes in tumor volume and tumor burden across the neoadjuvant treatment interval. Longitudinal registration errors of the pancreas were characterized, and registration-based treatment response measures were correlated to overall survival (OS) and recurrence-free survival (RFS) outcomes over 5-year follow-up. Corresponding biomarker assessments via manual tumor segmentation, the standardized response evaluation criteria in solid tumors (RECIST), and pathological examination of post-resection tissue samples were analyzed as clinical comparators.

Results

Average target registration errors were 2.56 ± 2.45    mm for a biomechanical image registration algorithm and 4.15 ± 3.63    mm for a diffeomorphic intensity-based algorithm, corresponding to 1-2 times voxel resolution. Cox proportional hazards analysis showed that registration-derived changes in tumor burden were significant predictors of OS and RFS, while none of the alternative comparators, including manual tumor segmentation, RECIST, or pathological variables were associated with consequential hazard ratios. Additional ROC analysis at 1-, 2-, 3-, and 5-year follow-up revealed that registration-derived changes in tumor burden between pre- and post-treatment imaging were better long-term predictors for OS and RFS than the clinical comparators.

Conclusions

Volumetric changes measured by longitudinal deformable image registration may yield imaging biomarkers to discriminate neoadjuvant treatment response in ill-defined tumors characteristic of PDAC. Registration-based biomarkers may help to overcome visual limits of radiographic evaluation to improve clinical outcome prediction and inform treatment selection.

Genomic Biomarkers Associated with Response to Induction Chemotherapy in Patients with Localized Pancreatic Ductal Adenocarcinoma

PURPOSE

There is increasing use of neoadjuvant chemotherapy in the management of localized pancreatic ductal adenocarcinoma (PDAC), yet there are few validated biomarkers to guide therapy selection. We aimed to determine whether somatic genomic biomarkers predict response to induction FOLFIRINOX or gemcitabine/nab-paclitaxel.

EXPERIMENTAL DESIGN

This single-institution cohort study included consecutive patients (N = 322) with localized PDAC (2011-2020) who received at least one cycle of FOLFIRINOX (N = 271) or gemcitabine/nab-paclitaxel (N = 51) as initial treatment. We assessed somatic alterations in four driver genes (KRAS, TP53, CDKN2A, and SMAD4) by targeted next-generation sequencing, and determined associations between these alterations and (1) rate of metastatic progression during induction chemotherapy, (2) surgical resection, and (3) complete/major pathologic response.

RESULTS

The alteration rates in driver genes KRAS, TP53, CDKN2A, and SMAD4 were 87.0%, 65.5%, 26.7%, and 19.9%, respectively. For patients receiving first-line FOLFIRINOX, SMAD4 alterations were uniquely associated with metastatic progression (30.0% vs. 14.5%; P = 0.009) and decreased rate of surgical resection (37.1% vs. 66.7%; P < 0.001). For patients receiving induction gemcitabine/nab-paclitaxel, alterations in SMAD4 were not associated with metastatic progression (14.3% vs. 16.2%; P = 0.866) nor decreased rate of surgical resection (33.3% vs. 41.9%; P = 0.605). Major pathologic response was rare (6.3%) and not associated with type of chemotherapy regimen.

CONCLUSIONS

SMAD4 alterations were associated with more frequent development of metastasis and lower probability of reaching surgical resection during neoadjuvant FOLFIRINOX but not gemcitabine/nab-paclitaxel. Confirmation in a larger, diverse patient cohort will be important before prospective evaluation of SMAD4 as a genomic biomarker to guide treatment selection.

Association of Inflammatory Biomarkers With Survival Among Patients With Stage III Colon Cancer

Importance

The association of chronic inflammation with colorectal cancer recurrence and death is not well understood, and data from large well-designed prospective cohorts are limited.

Objective

To assess the associations of inflammatory biomarkers with survival among patients with stage III colon cancer.

Design, Setting, and Participants

This cohort study was derived from a National Cancer Institute-sponsored adjuvant chemotherapy trial Cancer and Leukemia Group B/Southwest Oncology Group 80702 (CALGB/SWOG 80702) conducted between June 22, 2010, and November 20, 2015, with follow-up ending on August 10, 2020. A total of 1494 patients with plasma samples available for inflammatory biomarker assays were included. Data were analyzed from July 29, 2021, to February 27, 2022.

Exposures

Plasma inflammatory biomarkers (interleukin 6 [IL-6], soluble tumor necrosis factor α receptor 2 [sTNF-αR2], and high-sensitivity C-reactive protein [hsCRP]; quintiles) that were assayed 3 to 8 weeks after surgery but before chemotherapy randomization.

Main Outcomes and Measures

The primary outcome was disease-free survival, defined as time from randomization to colon cancer recurrence or death from any cause. Secondary outcomes were recurrence-free survival and overall survival. Hazard ratios for the associations of inflammatory biomarkers and survival were estimated via Cox proportional hazards regression.

Results

Of 1494 patients (median follow-up, 5.9 years [IQR, 4.7-6.1 years]), the median age was 61.3 years (IQR, 54.0-68.8 years), 828 (55.4%) were male, and 327 recurrences, 244 deaths, and 387 events for disease-free survival were observed. Plasma samples were collected at a median of 6.9 weeks (IQR, 5.6-8.1 weeks) after surgery. The median plasma concentration was 3.8 pg/mL (IQR, 2.3-6.2 pg/mL) for IL-6, 2.9 × 103 pg/mL (IQR, 2.3-3.6 × 103 pg/mL) for sTNF-αR2, and 2.6 mg/L (IQR, 1.2-5.6 mg/L) for hsCRP. Compared with patients in the lowest quintile of inflammation, patients in the highest quintile of inflammation had a significantly increased risk of recurrence or death (adjusted hazard ratios for IL-6: 1.52 [95% CI, 1.07-2.14]; P = .01 for trend; for sTNF-αR2: 1.77 [95% CI, 1.23-2.55]; P < .001 for trend; and for hsCRP: 1.65 [95% CI, 1.17-2.34]; P = .006 for trend). Additionally, a significant interaction was not observed between inflammatory biomarkers and celecoxib intervention for disease-free survival. Similar results were observed for recurrence-free survival and overall survival.

Conclusions and Relevance

This cohort study found that higher inflammation after diagnosis was significantly associated with worse survival outcomes among patients with stage III colon cancer. This finding warrants further investigation to evaluate whether anti-inflammatory interventions may improve colon cancer outcomes.

Trial Registration

ClinicalTrials.gov Identifier: NCT01150045.

Dietary fat in relation to all-cause mortality and cancer progression and death among people with metastatic colorectal cancer: Data from CALGB 80405 (Alliance)/SWOG 80405

Data on diet and survival among people with metastatic colorectal cancer are limited. We examined dietary fat in relation to all-cause mortality and cancer progression or death among 1149 people in the Cancer and Leukemia Group B (Alliance)/Southwest Oncology Group (SWOG) 80405 trial who completed a food frequency questionnaire at initiation of treatment for advanced or metastatic colorectal cancer. We examined saturated, monounsaturated, total and specific types (n-3, long-chain n-3 and n-6) of polyunsaturated fat, animal and vegetable fats. We hypothesized higher vegetable fat intake would be associated with lower risk of all-cause mortality and cancer progression. We used Cox proportional hazards regression to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI). Over median follow-up of 6.1 years (interquartile range [IQR]: 5.3, 7.2 y), we observed 974 deaths and 1077 events of progression or death. Participants had a median age of 59 y; 41% were female and 86% identified as White. Moderate or higher vegetable fat was associated with lower risk of mortality and cancer progression or death (HRs comparing second, third and fourth to first quartile for all-cause mortality: 0.74 [0.62, 0.90]; 0.75 [0.61, 0.91]; 0.79 [0.63, 1.00]; P trend: .12; for cancer progression or death: 0.74 [0.62, 0.89]; 0.78 [0.64, 0.95]; 0.71 [0.57, 0.88]; P trend: .01). No other fat type was associated with all-cause mortality and cancer progression or death. Moderate or higher vegetable fat intake may be associated with lower risk of cancer progression or death among people with metastatic colorectal cancer.

Comprehensive Molecular Characterization of Gallbladder Carcinoma and Potential Targets for Intervention

PURPOSE

Gallbladder carcinoma (GBC) is an uncommon and aggressive disease, which remains poorly defined at a molecular level. Here, we aimed to characterize the molecular landscape of GBC and identify markers with potential prognostic and therapeutic implications.

EXPERIMENTAL DESIGN

GBC samples were analyzed using the MSK-IMPACT (Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets) platform (targeted NGS assay that analyzes 505 cancer-associated genes). Variants with therapeutic implications were identified using OncoKB database. The associations between recurrent genetic alterations and clinicopathologic characteristics (Fisher exact tests) or overall survival (univariate Cox regression) were evaluated. P values were adjusted for multiple testing.

RESULTS

Overall, 244 samples (57% primary tumors and 43% metastases) from 233 patients were studied (85% adenocarcinomas, 10% carcinomas with squamous differentiation, and 5% neuroendocrine carcinomas). The most common oncogenic molecular alterations appeared in the cell cycle (TP53 63% and CDKN2A 21%) and RTK_RAS pathways (ERBB2 15% and KRAS 11%). No recurrent structural variants were identified. There were no differences in the molecular landscape of primary and metastasis samples. Variants in SMAD4 and STK11 independently associated with reduced survival in patients with metastatic disease. Alterations considered clinically actionable in GBC or other solid tumor types (e.g., NTRK1 fusions or oncogenic variants in ERBB2, PIK3CA, or BRCA1/2) were identified in 35% of patients; 18% of patients with metastatic disease were treated off-label or enrolled in a clinical trial based on molecular findings.

CONCLUSIONS

GBC is a genetically diverse malignancy. This large-scale genomic analysis revealed alterations with potential prognostic and therapeutic implications and provides guidance for the development of targeted therapies.

Efficacy of Preoperative mFOLFIRINOX vs mFOLFIRINOX Plus Hypofractionated Radiotherapy for Borderline Resectable Adenocarcinoma of the Pancreas: The A021501 Phase 2 Randomized Clinical Trial

Importance

National guidelines endorse treatment with neoadjuvant therapy for borderline resectable pancreatic ductal adenocarcinoma (PDAC), but the optimal strategy remains unclear.

Objective

To compare treatment with neoadjuvant modified FOLFIRINOX (mFOLFIRINOX) with or without hypofractionated radiation therapy with historical data and establish standards for therapy in borderline resectable PDAC.

Design, Setting, and Participants

This prospective, multicenter, randomized phase 2 clinical trial conducted from February 2017 to January 2019 among member institutions of National Clinical Trials Network cooperative groups used standardized quality control measures and included 126 patients, of whom 70 (55.6%) were registered to arm 1 (systemic therapy; 54 randomized, 16 following closure of arm 2 at interim analysis) and 56 (44.4%) to arm 2 (systemic therapy and sequential hypofractionated radiotherapy; all randomized before closure). Data were analyzed by the Alliance Statistics and Data Management Center during September 2021.

Interventions

Arm 1: 8 treatment cycles of mFOLFIRINOX (oxaliplatin, 85 mg/m2; irinotecan, 180 mg/m2; leucovorin, 400 mg/m2; and infusional fluorouracil, 2400 mg/m2) over 46 hours, administered every 2 weeks. Arm 2: 7 treatment cycles of mFOLFIRINOX followed by stereotactic body radiotherapy (33-40 Gy in 5 fractions) or hypofractionated image-guided radiotherapy (25 Gy in 5 fractions). Patients without disease progression underwent pancreatectomy, which was followed by 4 cycles of treatment with postoperative FOLFOX6 (oxaliplatin, 85 mg/m2; leucovorin, 400 mg/m2; bolus fluorouracil, 400 mg/m2; and infusional fluorouracil, 2400 mg/m2 over 46 hours).

Main Outcomes and Measures

Each treatment arm's 18-month overall survival (OS) rate was compared with a historical control rate of 50%. A planned interim analysis mandated closure of either arm for which 11 or fewer of the first 30 accrued patients underwent margin-negative (R0) resection.

Results

Of 126 patients, 62 (49%) were women, and the median (range) age was 64 (37-83) years. Among the first 30 evaluable patients enrolled to each arm, 17 patients in arm 1 (57%) and 10 patients in arm 2 (33%) had undergone R0 resection, leading to closure of arm 2 but continuation to full enrollment in arm 1. The 18-month OS rate of evaluable patients was 66.7% (95% CI, 56.1%-79.4%) in arm 1 and 47.3% (95% CI 35.8%-62.5%) in arm 2. The median OS of evaluable patients in arm 1 and arm 2 was 29.8 (95% CI, 21.1-36.6) months and 17.1 (95% CI, 12.8-24.4) months, respectively.

Conclusions and Relevance

This randomized clinical trial found that treatment with neoadjuvant mFOLFIRINOX alone was associated with favorable OS in patients with borderline resectable PDAC compared with mFOLFIRINOX treatment plus hypofractionated radiotherapy; thus, mFOLFIRINOX represents a reference regimen in this setting.

Trial Registration

ClinicalTrials.gov Identifier: NCT02839343.

Circulating tumor and invasive cell expression profiling predicts effective therapy in pancreatic cancer

BACKGROUND

Pancreatic adenocarcinoma (PDAC) remains a refractory disease; however, modern cytotoxic chemotherapeutics can induce tumor regression and extend life. A blood-based, pharmacogenomic, chemosensitivity assay using gene expression profiling of circulating tumor and invasive cells (CTICs) to predict treatment response was previously developed. The combination regimen of 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) and gemcitabine/nab-paclitaxel (G/nab-P) are established frontline approaches for treating advanced PDAC; however, there are no validated biomarkers for treatment selection. A similar unmet need exists for choosing second-line therapy.

METHODS

The chemosensitivity assay was evaluated in metastatic PDAC patients presenting for frontline treatment. A prospective study enrolled patients (n = 70) before receiving either FOLFIRINOX or G/nab-P at a 1:1 ratio. Six milliliters of peripheral blood was collected at baseline and at time of disease progression. CTICs were isolated, gene-expression profiling was performed, and the assay was used to predict effective and ineffective chemotherapeutic agents. Treating physicians were blinded to the assay prediction results.

RESULTS

Patients receiving an effective regimen as predicted by the chemosensitivity assay experienced significantly longer median progression-free survival (mPFS; 7.8 months vs. 4.2 months; hazard ratio [HR], 0.35; p = .0002) and median overall survival (mOS; 21.0 months vs. 9.7 months; HR, 0.40; p = .005), compared with an ineffective regimen. Assay prediction for effective second-line therapy was explored. The entire study cohort experienced favorable outcomes compared with historical controls, 7.1-month mPFS and 12.3-month mOS.

CONCLUSIONS

Chemosensitivity assay profiling is a promising tool for guiding therapy in advanced PDAC. Further prospective validation is under way (clinicaltrials.gov NCT03033927).

Everolimus with or without bevacizumab in advanced pNET: CALGB 80701 (Alliance)

Treatment with the MTOR inhibitor everolimus improves progression-free survival (PFS) in pancreatic neuroendocrine tumors (pNETs), but it is not known if the addition of a VEGF pathway inhibitor to an MTOR inhibitor enhances antitumor activity. We performed a randomized phase II study evaluating everolimus with or without bevacizumab in patients with advanced pNETs. One hundred and fifty patients were randomized to receive everolimus 10 mg daily with or without bevacizumab 10 mg/kg i.v. every 2 weeks. Patients also received standard dose of octreotide in both arms. The primary endpoint was PFS, based on local investigator review. Treatment with the combination of everolimus and bevacizumab resulted in improved progression-free survival compared to everolimus (16.7 months compared to 14.0 months; one-sided stratified log-rank P = 0.1028; hazard ratio (HR) 0.80 (95% CI 0.56-1.13)), meeting the predefined primary endpoint. Confirmed tumor responses were observed in 31% (95% CI 20%, 41%) of patients receiving combination therapy, as compared to only 12% (95% CI 5%, 19%) of patients receiving treatment with everolimus (P = 0.0053). Median overall survival duration was similar in the everolimus and combination arm (42.5 and 42.1 months, respectively). Treatment-related toxicities were more common in the combination arm. In summary, treatment with everolimus and bevacizumab led to superior PFS and higher response rates compared to everolimus in patients with advanced pNETs. Although the higher rate of treatment-related adverse events may limit the use of this combination, our results support the continued evaluation of VEGF pathway inhibitors in pNETs.

Survival in Young-Onset Metastatic Colorectal Cancer: Findings From Cancer and Leukemia Group B (Alliance)/SWOG 80405

BACKGROUND

The incidence of young-onset colorectal cancer (yoCRC) is increasing. It is unknown if there are survival differences between young and older patients with metastatic colorectal cancer (mCRC).

METHODS

We studied the association of age with survival in 2326 mCRC patients enrolled in the Cancer and Leukemia Group B and SWOG 80405 trial, a multicenter, randomized trial of first-line chemotherapy plus biologics. The primary and secondary outcomes of this study were overall survival (OS) and progression-free survival (PFS), respectively, which were assessed by Kaplan-Meier method and compared among younger vs older patients with the log-rank test. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated based on Cox proportional hazards modeling, adjusting for known prognostic variables. All statistical tests were 2-sided.

RESULTS

Of 2326 eligible subjects, 514 (22.1%) were younger than age 50 years at study entry (yoCRC cohort). The median age of yoCRC patients was 44.3 vs 62.5 years in patients aged 50 years and older. There was no statistically significant difference in OS between yoCRC vs older-onset patients (median = 27.07 vs 26.12 months; adjusted HR = 0.98, 95% CI = 0.88 to 1.10; P = .78). The median PFS was also similar in yoCRC vs older patients (10.87 vs 10.55 months) with an adjusted hazard ratio of 1.02 (95% CI = 0.92 to 1.13; P = .67). Patients younger than age 35 years had the shortest OS with median OS of 21.95 vs 26.12 months in older-onset patients with an adjusted hazard ratio of 1.08 (95% CI = 0.81 to 1.44; Ptrend = .93).

CONCLUSION

In this large study of mCRC patients, there were no statistically significant differences in survival between patients with yoCRC and CRC patients aged 50 years and older.

Induction FOLFIRINOX for patients with locally unresectable pancreatic ductal adenocarcinoma

OBJECTIVES

Patients with locally advanced pancreatic adenocarcinoma (PDAC) receive induction chemotherapy with or without radiation, with the goal of R0 resection and improving survival. Herein, we evaluate the outcomes of patients who presented with Stage III PDAC and received induction FOLFIRINOX.

METHODS

An institutional database was queried for consecutive patients who received induction FOLFIRINOX for locally unresectable PDAC between 2010 and 2016. Clinical and radiographic parameters were assessed pre- and posttreatment, and clinical outcomes were evaluated.

RESULTS

There were 200 patients who met the inclusion criteria. The median number of cycles of FOLFIRINOX was 8, 70% (n = 140) received radiation, and 18% (n = 36) underwent resection. Median overall survival (OS) in resected patients was 36 months (95% confidence interval [CI]: 24-56), and this group had improved OS compared to patients that did not undergo resection (hazard ratio (95% CI): 0.41 (0.26-0.64), p < 0.001). Patients (n = 112) who did not progress on induction therapy but remained unresectable had a median OS of 23.9 months (95% CI: 21.1-25.4).

CONCLUSION

Nearly 20% of patients with locally advanced PDAC responded sufficiently to induction FOLFIRINOX to undergo resection, which was associated with improved OS compared to patients that did not undergo resection. Patients with stable disease who remain unresectable represent a group of patients with locally advanced PDAC who may benefit from optimization of additional nonoperative treatment.

Methylation Analyses Reveal Promoter Hypermethylation as a Rare Cause of "Second Hit" in Germline BRCA1-Associated Pancreatic Ductal Adenocarcinoma

BACKGROUND AND OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is characterized by the occurrence of pathogenic variants in BRCA1/2 in 5-6% of patients. Biallelic loss of BRCA1/2 enriches for response to platinum agents and poly (ADP-ribose) polymerase 1 inhibitors. There is a dearth of evidence on the mechanism of inactivation of the wild-type BRCA1 allele in PDAC tumors with a germline BRCA1 (gBRCA1) pathogenic or likely pathogenic variant (P/LPV). Herein, we examine promotor hypermethylation as a "second hit" mechanism in patients with gBRCA1-PDAC.

METHODS

We evaluated patients with PDAC who underwent Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) somatic and germline testing from an institutional database. DNA isolated from tumor tissue and matched normal peripheral blood were sequenced by MSK-IMPACT. In patients with gBRCA1-PDAC, we examined the somatic BRCA1 mutation status and promotor methylation status of the tumor BRCA1 allele via a methylation array analysis. In patients with sufficient remaining DNA, a second methylation analysis by pyrosequencing was performed.

RESULTS

Of 1012 patients with PDAC, 19 (1.9%) were identified to harbor a gBRCA1 P/LPV. Fifteen patients underwent a methylation array and the mean percentage of BRCA1 promotor methylation was 3.62%. In seven patients in whom sufficient DNA was available, subsequent pyrosequencing confirmed an unmethylated BRCA1 promotor. Loss of heterozygosity was detected in 12 of 19 (63%, 95% confidence interval 38-84) patients, demonstrating loss of heterozygosity is the major molecular mechanism of BRCA1 inactivation in PDAC. Two (10.5%) cases had a somatic BRCA1 mutation.

CONCLUSIONS

In patients with gBRCA1-P/LPV-PDAC, loss of heterozygosity is the main inactivating mechanism of the wild-type BRCA1 allele in the tumor, and methylation of the BRCA1 promoter is a distinctly uncommon occurrence.

Multimodality therapy in metastatic pancreas cancer with a BRCA mutation and durable long-term outcome: biology, intervention, or both?

Metastatic pancreatic adenocarcinoma (PDAC) is a rapidly lethal disease, with less than half of patients surviving 12 months, and 5-year survival approximately 3%. These outcomes are in large part due to a lack of effective medical and surgical therapies for metastatic PDAC. Herein, we present the case of a patient with oligometastatic liver recurrence of BRCA2-mutated PDAC following a curative-intent resection. Through a combination of systemic chemotherapy, metastasectomy, radiotherapy, and subsequent targeted therapy with olaparib, the patient is asymptomatic four years following metastatic diagnosis with stable low-volume disease. This patient's excellent outcome is attributable to the multi-disciplinary care received, all aspects of which were informed by new evidence surrounding metastasectomy for metastatic PDAC, the unique biology and medical treatment of BRCA-mutated PDAC, and the role of radiotherapy in controlling locoregional recurrence. We provide a review of this evidence, while highlighting the importance of evaluating disease biology through somatic and germline genetic testing as well as monitoring response to systemic chemotherapy.

Local Control and Survival After Induction Chemotherapy and Ablative Radiation Versus Resection for Pancreatic Ductal Adenocarcinoma With Vascular Involvement

OBJECTIVE

We sought to compare overall survival (OS) and disease control for patients with localized pancreatic ductal adenocarcinoma (PDAC) treated with ablative dose radiotherapy (A-RT) versus resection.

SUMMARY BACKGROUND DATA

Locoregional treatment for PDAC includes resection when possible or palliative RT. A-RT may offer durable tumor control and encouraging survival.

METHODS

This was a single-institution retrospective analysis of patients with PDAC treated with induction chemotherapy followed by A-RT [≥98 Gy biologically effective dose (BED) using 15-25 fractions in 3-4.5 Gy/fraction] or pancreatectomy.

RESULTS

One hundred and four patients received A-RT (49.8%) and 105 (50.2%) underwent resection. Patients receiving A-RT had larger median tumor size after induction chemotherapy [3.2 cm (undetectable-10.9) vs 2.6 cm (undetectable-10.7), P < 0.001], and were more likely to have celiac or hepatic artery encasement (48.1% vs 11.4%, P <0.001), or superior mesenteric artery encasement (43.3% vs 9.5%, P < 0.001); however, there was no difference in the degree of SMV/PV involvement (P = 0.123). There was no difference in locoregional recurrence/progression at 18-months between A-RT and resection; cumulative incidence was 16% [(95% confidence interval (CI) 10%-24%] versus 21% (95% CI 14%-30%), respectively (P= 0.252). However, patients receiving A-RT had a 19% higher 18-month cumulative incidence of distant recurrence/progression [58% (95% CI 48%-67%) vs 30% (95% CI 30%-49%), P= 0.004]. Median OS from completion of chemotherapy was 20.1 months for A-RT patients (95% CI 16.4-23.1 months) versus 32.9 months (95% CI 29.7-42.3 months) for resected patients (P < 0.001).

CONCLUSION

Ablative radiation is a promising new treatment option for PDAC, offering locoregional disease control similar to that associated with resection and encouraging survival.

Early-Onset Pancreas Cancer: Clinical Descriptors, Genomics, and Outcomes

BACKGROUND

Recent evidence suggests a rising incidence of cancer in younger individuals. Herein, we report the epidemiologic, pathologic, and molecular characteristics of a patient cohort with early-onset pancreas cancer (EOPC).

METHODS

Institutional databases were queried for demographics, treatment history, genomic results, and outcomes. Overall survival from date of diagnosis was estimated using Kaplan-Meier method.

RESULTS

Between 2008 and 2018, 450 patients with EOPC were identified at Memorial Sloan Kettering. Median overall survival was 16.3  (95% confidence interval [CI] = 14.6 to 17.7) months in the entire cohort and 11.3  (95% CI = 10.2 to 12.2) months for patients with stage IV disease at diagnosis. Of the patients, 132 (29.3% of the cohort) underwent somatic testing; 21 of 132 (15.9%) had RAS wild-type cancers with identification of several actionable alterations, including ETV6-NTRK3, TPR-NTRK1, SCLA5-NRG1, and ATP1B1-NRG1 fusions, IDH1 R132C mutation, and mismatch repair deficiency. A total of 138 patients (30.7% of the cohort) underwent germline testing; 44 of 138 (31.9%) had a pathogenic germline variant (PGV), and 27.5% harbored alterations in cancer susceptibility genes. Of patients seen between 2015 and 2018, 30 of 193 (15.5%) had a PGV. Among 138 who underwent germline testing, those with a PGV had a reduced all-cause mortality compared with patients without a PGV controlling for stage and year of diagnosis (hazard ratio = 0.42, 95% CI = 0.26 to 0.69).

CONCLUSIONS

PGVs are present in a substantial minority of patients with EOPC. Actionable somatic alterations were identified frequently in EOPC, enriched in the RAS wild-type subgroup. These observations underpin the recent guidelines for universal germline testing and somatic profiling in pancreatic ductal adenocarcinoma.

Targeting DNA Damage Repair Mechanisms in Pancreas Cancer

Impaired DNA damage repair (DDR) is increasingly recognised as a hallmark in pancreatic ductal adenocarcinoma (PDAC). It is estimated that around 14% of human PDACs harbour mutations in genes involved in DDR, including, amongst others, BRCA1/2, PALB2, ATM, MSH2, MSH6 and MLH1. Recently, DDR intervention by PARP inhibitor therapy has demonstrated effectiveness in germline BRCA1/2-mutated PDAC. Extending this outcome to the significant proportion of human PDACs with somatic or germline mutations in DDR genes beyond BRCA1/2 might be beneficial, but there is a lack of data, and consequently, no clear recommendations are provided in the field. Therefore, an expert panel was invited by the European Society of Digestive Oncology (ESDO) to assess the current knowledge and significance of DDR as a target in PDAC treatment. The aim of this virtual, international expert meeting was to elaborate a set of consensus recommendations on testing, diagnosis and treatment of PDAC patients with alterations in DDR pathways. Ahead of the meeting, experts completed a 27-question survey evaluating the key issues. The final recommendations herein should aid in facilitating clinical practice decisions on the management of DDR-deficient PDAC.

Effect of Celecoxib vs Placebo Added to Standard Adjuvant Therapy on Disease-Free Survival Among Patients With Stage III Colon Cancer: The CALGB/SWOG 80702 (Alliance) Randomized Clinical Trial

Importance

Aspirin and cyclooxygenase 2 (COX-2) inhibitors have been associated with a reduced risk of colorectal polyps and cancer in observational and randomized studies. The effect of celecoxib, a COX-2 inhibitor, as treatment for nonmetastatic colon cancer is unknown.

Objective

To determine if the addition of celecoxib to adjuvant chemotherapy with fluorouracil, leucovorin, and oxaliplatin (FOLFOX) improves disease-free survival in patients with stage III colon cancer.

Design, Setting, and Participants

Cancer and Leukemia Group B (Alliance)/Southwest Oncology Group 80702 was a 2 × 2 factorial design, phase 3 trial conducted at 654 community and academic centers throughout the United States and Canada. A total of 2526 patients with stage III colon cancer were enrolled between June 2010 and November 2015 and were followed up through August 10, 2020.

Interventions

Patients were randomized to receive adjuvant FOLFOX (every 2 weeks) for 3 vs 6 months with or without 3 years of celecoxib (400 mg orally daily; n = 1263) vs placebo (n = 1261). This report focuses on the results of the celecoxib randomization.

Main Outcomes and Measures

The primary end point was disease-free survival, measured from the time of randomization until documented recurrence or death from any cause. Secondary end points included overall survival, adverse events, and cardiovascular-specific events.

Results

Of the 2526 patients who were randomized (mean [SD] age, 61.0 years [11 years]; 1134 women [44.9%]), 2524 were included in the primary analysis. Adherence with protocol treatment, defined as receiving celecoxib or placebo for more than 2.75 years or continuing treatment until recurrence, death, or unacceptable adverse events, was 70.8% for patients treated with celecoxib and 69.9% for patients treated with placebo. A total of 337 patients randomized to celecoxib and 363 to placebo experienced disease recurrence or died, and with 6 years' median follow-up, the 3-year disease-free survival was 76.3% for celecoxib-treated patients vs 73.4% for placebo-treated patients (hazard ratio [HR] for disease recurrence or death, 0.89; 95% CI, 0.76-1.03; P = .12). The effect of celecoxib treatment on disease-free survival did not vary significantly according to assigned duration of adjuvant chemotherapy (P for interaction = .61). Five-year overall survival was 84.3% for celecoxib vs 81.6% for placebo (HR for death, 0.86; 95% CI, 0.72-1.04; P = .13). Hypertension (any grade) occurred while treated with FOLFOX in 14.6% of patients in the celecoxib group vs 10.9% of patients in the placebo group, and a grade 2 or higher increase in creatinine levels occurred after completion of FOLFOX in 1.7% vs 0.5% of patients, respectively.

Conclusions and Relevance

Among patients with stage III colon cancer, the addition of celecoxib for 3 years, compared with placebo, to standard adjuvant chemotherapy did not significantly improve disease-free survival.

Trial Registration

ClinicalTrials.gov Identifier: NCT01150045.

Noninvasive Detection of Polyclonal Acquired Resistance to FGFR Inhibition in Patients With Cholangiocarcinoma Harboring FGFR2 Alterations

PURPOSE

Fibroblast growth factor receptor (FGFR) 2 alterations, present in 5%-15% of intrahepatic cholangiocarcinomas (IHC), are targets of FGFR-directed therapies. Acquired resistance is common among patients who respond. Biopsies at the time of acquired resistance to targeted agents may not always be feasible and may not capture the genetic heterogeneity that could exist within a patient. We studied circulating tumor DNA (ctDNA) as a less invasive means of potentially identifying genomic mechanisms of resistance to FGFR-targeted therapies.

MATERIALS AND METHODS

Serial blood samples were collected from eight patients with FGFR-altered cholangiocarcinoma for ctDNA isolation and next-generation sequencing (NGS) throughout treatment and at resistance to anti-FGFR-targeted therapy. ctDNA was sequenced using a custom ultra-deep coverage NGS panel, incorporating dual index primers and unique molecular barcodes to enable high-sensitivity mutation detection.

RESULTS

Thirty-one acquired mutations in FGFR2, 30/31 located in the kinase domain, were identified at resistance in six of eight patients with detectable ctDNA. Up to 13 independent FGFR2 mutations were detected per patient, indicative of striking genomic concordance among resistant subclones.

CONCLUSION

ctDNA could be an effective means to longitudinally monitor for acquired resistance in FGFR2-altered IHC. The numerous acquired genetic alterations in FGFR2 suggest frequent polyclonal mechanisms of resistance that cannot be detected from single-site tissue biopsies.

Phase II trial of sorafenib and doxorubicin in patients with advanced hepatocellular carcinoma after disease progression on sorafenib

Background

Patients with advanced hepatocellular carcinoma (HCC) who received second line sorafenib plus doxorubicin following disease progression on sorafenib were shown retrospectively to have improved progression free survival (PFS) and overall survival (OS). Sorafenib plus doxorubicin combination may synergistically promote ASK‐1 mediated apoptosis in cancer cells through RAF‐1 inhibition. Thus, we conducted this phase II study of sorafenib and doxorubicin combination following progression on sorafenib.

Methods

Patients with histologically confirmed advanced HCC, confirmed radiologic progression on sorafenib, Karnofsky performance status (KPS) ≥70%, and Child‐Pugh A liver cirrhosis were eligible. Patients received sorafenib 400 mg twice daily and doxorubicin 60 mg/m² once every 3‐weeks. The primary endpoint was OS at 6 months (OS6). Secondary endpoints included safety, PFS, OS, response rate (RR) by RECIST 1.1. Additional endpoints included baseline and on‐treatment tumor ASK‐1 and pERK expression levels by immunohistochemistry (IHC) and the correlation with PFS, RR, and OS.

Results

Thirty patients were enrolled in the study, 86% were male, median age was 64 years. OS6 was 76.6% (95%CI: 57.2%‐88.1%). Median OS was 8.6 (95%CI: 7.3‐12) months, and median PFS reached 3.9 (95%CI: 2.4‐4.6) months. Three (11%) partial responses were observed and 17 patients (61%) had stable disease. Pertinent grade 3‐4 adverse events that occurred in more than 10% of patients included neutropenia (16%), febrile neutropenia (10%), anemia (10%), thrombocytopenia (10%), elevated AST (23%) and ALT (10%), hypophosphatemia (10%), and fatigue (10%). No association with the difference in baseline and post‐treatment ASK‐1 and pERK level of expression by IHC and survival outcomes was detected.

Conclusion

Sorafenib plus doxorubicin following progression on sorafenib did not show any improved outcome. We do not recommend further development or use of this combination in HCC.

Advances in the Management of Pancreatic Adenocarcinoma

Outcomes in pancreatic cancer are improving. The beneficial effects being achieved with adjuvant and neoadjuvant therapies, and the recent application of molecular profiling, both germline and somatic, are collectively impacting survival. The NCCN Guidelines for Pancreatic Cancer urge clinicians to undertake “agnostic” germline testing for all persons with pancreatic cancer. Fit patients should also be considered for adjuvant therapy with modified FOLFIRINOX (leucovorin, 5-FU, irinotecan, oxaliplatin). Novel therapies that focus on DNA damage repair strategies are proving to be important, but notably several late-stage trials of several other approaches, reported in the last year, proved disappointing.

Randomized, Multicenter, Phase II Trial of Gemcitabine and Cisplatin With or Without Veliparib in Patients With Pancreas Adenocarcinoma and a Germline BRCA/PALB2 Mutation

PURPOSE

Five percent to 9% of pancreatic ductal adenocarcinomas (PDACs) develop in patients with a germline BRCA1/2 or PALB2 (gBRCA/PALB2+) mutation. Phase IB data from a trial that used cisplatin, gemcitabine, and veliparib treatment demonstrated a high response rate (RR), disease control rate (DCR), and overall survival (OS) in this population. We designed an open-label, randomized, multicenter, two-arm phase II trial to investigate cisplatin and gemcitabine with or without veliparib in gBRCA/PALB2+ PDAC.

PATIENTS AND METHODS

Eligible patients had untreated gBRCA/PALB2+ PDAC with measurable stage III to IV disease and Eastern Cooperative Oncology Group performance status of 0 to 1. Treatment for patients in arm A consisted of cisplatin 25 mg/m2 and gemcitabine 600 mg/m2 intravenously on days 3 and 10; treatment for patients in arm B was the same as that for patients in arm A, and arm A also received veliparib 80 mg orally twice per day on days 1 to 12 cycled every 3 weeks. The primary end point was RRs of arm A and arm B evaluated separately using a Simon two-stage design. Secondary end points were progression-free survival, DCR, OS, safety, and correlative analyses.

RESULTS

Fifty patients were evaluated by modified intention-to-treat analysis. The RR for arm A was 74.1% and 65.2% for arm B (P = .55); both arms exceeded the prespecified activity threshold. DCR was 100% for arm A and 78.3% for arm B (P = .02). Median progression-free survival was 10.1 months for arm A (95% CI, 6.7 to 11.5 months) and 9.7 months for arm B (95% CI, 4.2 to 13.6 months; P = .73). Median OS for arm A was 15.5 months (95% CI, 12.2 to 24.3 months) and 16.4 months for arm B (95% CI, 11.7 to 23.4 months; P = .6). Two-year OS rate for the entire cohort was 30.6% (95% CI, 17.8% to 44.4%), and 3-year OS rate was 17.8% (95% CI, 8.1% to 30.7%). Grade 3 to 4 hematologic toxicities for arm A versus arm B were 13 (48%) versus seven (30%) for neutropenia, 15 (55%) versus two (9%) for thrombocytopenia, and 14 (52%) versus eight (35%) for anemia.

CONCLUSION

Cisplatin and gemcitabine is an effective regimen in advanced gBRCA/PALB2+ PDAC. Concurrent veliparib did not improve RR. These data establish cisplatin and gemcitabine as a standard approach in gBRCA/PALB2+ PDAC.

A mixed methods analysis of patients' advance care planning values in outpatient oncology: Person-Centered Oncologic Care and Choices (P-COCC)

PURPOSE

Person-Centered Oncologic Care and Choices (P-COCC) combines an advance care planning (ACP) value-focused patient interview with a care goal video decision aid. Our randomized study showed that P-COCC was acceptable but increased participant distress, compared with video-alone and usual care study arms. This mixed methods approach explores the ACP values in the P-COCC arm and their relationship to the distress phenomenon.

METHODS

Qualitative thematic analysis of the 46 audio-recorded P-COCC interview transcripts with advanced gastrointestinal cancer patients was performed by multiple reviewers. Quantitative (Likert scale) changes in ACP values were compared across study arms. ACP themes and value change were analyzed in participants with increased distress.

RESULTS

Transcript analysis resulted in thematic saturation and identified eight distinct themes on ACP values relating to end-of-life wishes, communication needs, and psychosocial supports. Of 98 participants (33 P-COCC, 43 videos, 22 usual care) who completed the change in value measure, there was no difference detected with P-COCC compared with either video (p = 0.052) or usual care (p = 0.105) arms alone, but P-COCC led to a frequency distribution of more change in personal values compared with the other study arms combined (p = 0.043). Among the subset of P-COCC participants with increased distress, there was no statistical relationship with change in values.

CONCLUSIONS

The ACP paradigm P-COCC both informs and supports patients in individualized, value-based decision-making. Distress is not associated with changes in ACP values and may be a necessary, at least transient, byproduct of discussing sensitive but pertinent topics about end-of-life medical care.

Second-line chemotherapy in advanced biliary cancers: A retrospective, multicenter analysis of outcomes

BACKGROUND

Although gemcitabine plus platinum chemotherapy is the established first-line regimen for advanced biliary cancer (ABC), there is no standard second-line therapy. This study evaluated current practice and outcomes for second-line chemotherapy in patients with ABC across 3 US academic medical centers.

METHODS

Institutional registries were reviewed to identify patients who had received second-line chemotherapy for ABC from April 2010 to March 2015 along with their demographics, diagnoses and staging, treatment histories, and clinical outcomes. Overall survival from the initiation of second-line chemotherapy (OS2) was estimated with Kaplan-Meier methods.

RESULTS

This study identified 198 patients with cholangiocarcinoma (intrahepatic [61.1%] or extrahepatic [14.1%]) or gallbladder carcinoma (24.8%); 52% received at least 3 lines of systemic chemotherapy. The median OS2 was 11 months (95% confidence interval [CI], 8.8-13.1 months). The median OS2 for patients with intrahepatic cholangiocarcinoma was 13.4 months (95% CI, 10.7-17.8 months), which was longer than that for patients with extrahepatic cholangiocarcinoma (6.8 months; 95% CI, 5-10.6 months) or gallbladder carcinoma (9.4 months; 95% CI, 7.2-12.3 months; P = .018). The median time to second-line treatment failure was 2.2 months (95% CI, 1.8-2.7 months), and it was similar across tumor locations (P = .60).

CONCLUSIONS

In this large cohort of patients with ABC treated across 3 academic medical centers after the failure of first-line chemotherapy, the time to treatment failure on standard therapies was short, although the median OS2 was longer than has been reported previously, and more than half of the patients received additional lines of treatment. This multicenter collaboration represents the largest cohort studied to date of second-line chemotherapy for ABC and provides a contemporary benchmark for future clinical trials.

Abstract PR02: Clinical proof of concept for MCLA-128, a bispecific HER2/3 antibody therapy, in NRG1 fusion-positive cancers

Background: NRG1 fusions are oncogenic drivers of various cancers including pancreatic and lung adenocarcinomas. NRG1 fusion proteins bind to HER3, leading to HER2/HER3 heterodimerization, increased downstream signaling, and tumor growth. MCLA-128 is a bispecific antibody directed against HER2 and HER3 that docks on HER2 and blocks ligand binding to HER3, thereby preventing downstream signaling. In contrast to tyrosine kinase inhibitors or anti-HER3 monoclonal antibodies, MCLA-128 was shown in vitro and in vivo to potently inhibit ligand-driven tumor growth at high NRG1 levels present in NRG1 fusion-positive cancers. MCLA-128 offers a novel therapeutic paradigm for NRG1 fusion-positive cancers. MCLA-128 has a very well tolerated safety profile with &lt;5% of patients reporting grade 3-4 suspected related AEs, and a notable lack of cardiotoxicity and severe gastrointestinal or skin toxicity. Methods: Cell line/xenograft models with NRG1 fusions (MDA-MB-175, OV5383, OV10-0050) were treated with MCLA-128. Patients with cancers harboring NRG1 fusions were identified using prospective molecular profiling by DNA/RNA-based next-generation sequencing (NGS). Patients with NRG1 fusion-positive tumors were treated with MCLA-128 (750 mg intravenously, every 2 weeks) on FDA-approved single-patient protocols. Results: Treatment with MCLA-128 inhibited proliferation of NRG1-fusion positive cell lines in vitro and resulted in rapid tumor shrinkage in NRG1 fusion-positive xenograft models in vivo. NGS identified 29 patients with NRG1 fusions across 8 tumor types (pancreas, lung, breast, sarcoma, prostate, gallbladder, unknown primary, and DLBCL). Of these 29 patients, 3 with chemotherapy-resistant metastatic cancer were treated with MCLA-128 and experienced dramatic clinical and radiographic responses. A 52-year-old man with ATP1B1-NRG1 fusion-positive pancreatic ductal adenocarcinoma (PDAC) with liver metastases, worsening fatigue, and weight loss, achieved rapid clinical and pharmacodynamic responses (CA19-9 decrease from 262 to 56). Imaging at 8 weeks demonstrated a partial response (-44%) by RECIST v1.1 and a complete response by PERCIST. A 34-year-old man with ATP1B1-NRG1 fusion-positive PDAC and longstanding tumor-associated abdominal pain also achieved rapid resolution of his pain, and normalization of CA 19-9 (418 to 11) upon treatment with MCLA-128. Imaging at 6 weeks showed tumor reduction (-22%) and that the liver metastases were non-FDG avid. A third patient with CD74-NRG1 fusion-positive non-small cell lung cancer (NSCLC) metastatic to the brain was started on MCLA-128. Despite progression on 6 prior lines of systemic therapy including afatinib, he rapidly responded to MCLA-128 with scans showing a partial response (-33%) by RECIST v1.1 at 8 weeks and tumor shrinkage in the brain. All patients remain on therapy (6+ months into treatment for the PDAC patients, 2+ months for the NSCLC patient) with no substantial toxicity. Conclusions: MCLA-128 leads to clinical responses in patients with NRG1 fusion-positive cancers through inhibition of ligand-driven activation of the HER3 pathway. A global, multicenter phase 2 basket trial for NRG1 fusion-positive cancers is now accruing patients.

Citation Format: Alison M Schram, Eileen M O’Reilly, Romel Somwar, Ryma Benayed, Sara Shameem, Thrusha Chauhan, Jean Torrisi, Jim Ford, David Maussang, Ernesto Wasserman, Marc Ladanyi, David M Hyman, L. Andres Sirulnik, Alexander Drilon. Clinical proof of concept for MCLA-128, a bispecific HER2/3 antibody therapy, in NRG1 fusion-positive cancers [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr PR02. doi:10.1158/1535-7163.TARG-19-PR02

Pancreatic cancer-A disease in need: Optimizing and integrating supportive care

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy that continues to be challenging to treat. PDAC has the lowest 5-year relative survival rate compared with all other solid tumor malignancies and is expected to become the second-leading cause of cancer-related death in the United States by 2030. Given the high mortality, there is an increasing role for concurrent anticancer and supportive care in the management of patients with PDAC with the aims of maximizing length of life, quality of life, and symptom control. Emerging trends in supportive care that can be integrated into the clinical management of patients with PDAC include standardized supportive care screening, early integration of supportive care into routine cancer care, early implementation of outpatient-based advance care planning, and utilization of electronic patient-reported outcomes for improved symptom management and quality of life. The most common symptoms experienced are nausea, constipation, weight loss, diarrhea, anorexia, and abdominal and back pain. This review article includes current supportive management strategies for these and others. Common disease-related complications include biliary and duodenal obstruction requiring endoscopic procedures and venous thromboembolic events. Patients with PDAC continue to have a poor prognosis. Systemic therapy options are able to palliate the high symptom burden but have a modest impact on overall survival. Early integration of supportive care can lead to improved outcomes.

Tumour response to TRK inhibition in a patient with pancreatic adenocarcinoma harbouring an NTRK gene fusion

BACKGROUND

Although rare, NTRK gene fusions are known to be oncogenic drivers in pancreatic ductal adenocarcinoma (PDAC). We report the response of a metastatic CTRC-NTRK1 gene fusion-positive PDAC to targeted treatment with the oral tropomyosin receptor kinase (TRK) inhibitor larotrectinib and the eventual development of resistance to treatment.

PATIENT, METHODS AND RESULTS

A 61-year-old woman presented with a 2.5-cm mass in the body of the pancreas and a 1.2-cm liver lesion on routine follow-up for endometrial cancer that was in complete remission. Liver biopsy confirmed a primary PDAC unrelated to the endometrial cancer. The patient was treated with gemcitabine, nab-paclitaxel and ADI-PEG 20 for 12 months until disease progression and toxicity emerged [best overall response (BOR): partial response (PR)]. The patient switched to a modified regimen of folinic acid, fluorouracil, irinotecan and oxaliplatin for 4 months until neuropathy occurred. Oxaliplatin was withheld until disease progression 6 months later (BOR: stable disease). Despite recommencing oxaliplatin, the disease continued to progress. At this time, somatic profiling of the liver lesion revealed a CTRC-NTRK1 gene fusion. Treatment with larotrectinib 100 mg twice daily was commenced with BOR of PR at 2 months. The patient progressed after 6 months and was re-biopsied. Treatment was switched to the investigational next-generation TRK inhibitor selitrectinib (BAY 2731954, LOXO-195) 100 mg twice daily. After 2 months, the disease progressed and dabrafenibtrametinib combination therapy was initiated due to existence of a BRAF-V600E mutation. However, the cancer continued to progress and the patient died 2 months later.

CONCLUSIONS

Targeted TRK inhibition with larotrectinib in PDAC harbouring a CTRC-NTRK1 gene fusion is well tolerated and can improve quality of life for the patient. However, acquired resistance to therapy can emerge in some patients. Next-generation TRK inhibitors such as selitrectinib are currently in development to overcome this resistance (NCT02576431; NCT03215511).

Evolution of surgical management of gallbladder carcinoma and impact on outcome: results from two decades at a single-institution

BACKGROUND

The surgical approach to gallbladder cancer (GBCA) has evolved in recent years, but the impact on outcomes is unknown. This study describes differences in presentation, surgery, chemotherapy strategy, and survival for patients with GBCA over two decades at a tertiary referral center.

METHODS

A single-institution database was queried for patients with GBCA who underwent surgical evaluation and exploration and was studied retrospectively. Univariate logistic regression was used to assess the relationship between time and treatment. Univariate Cox proportional hazard regression assessed the association between year of diagnosis and survival.

RESULTS

From 1992 to 2015, 675 patients with GBCA were evaluated and 437 underwent exploration. Complete resection rates increased over time (p < 0.001). In those submitted to complete resection (n = 255, 58.4%), more recent years were associated with lower likelihood of bile duct resection and major hepatectomy but greater odds of neoadjuvant and adjuvant chemotherapy (p < 0.05). No significant association was found between year of diagnosis and OS or RFS (p > 0.05) for patients with complete resection.

CONCLUSION

Over the study period, GBCA treatment evolved to include fewer biliary and major hepatic resections with no apparent adverse impact on outcome. Further prospective trials, specifically limited to GBCA, are needed to determine the impact of adjuvant chemotherapy.

Incidence of Asymptomatic Chiari Malformation

Aim The aim of this study is to define the incidence of asymptomatic Chiari malformation in an Irish population. Methods MRIs performed over 24 months were analysed. Exclusion criteria include: space occupying lesion, hydrocephalus, Chiari symptoms and inadequate views. Data were analysed to give incidence of asymptomatic Chiari and to analyze the relationship between symptom and position of the cerebellar tonsils (Chi square and Fishers exact test). Results Sample Characteristics: 147 patients (Male = 65: Female = 82), age range 15 to 93 years (M age = 53.35, SD= 16.67). 2%had a Chiari malformation (n=2). There was no significant association between symptom and tonsil position (Fishers exact test, ² (8) = 9.98, p = .23.) Conclusion This study shows an asymptomatic Chiari Malformation rate of 2%. This study supports the idea that in asymptomatic patients, a tonsil herniation of up to 5 millimeters may be an incidental and inconsequent finding.

Abstract 1752: BRCA-mediated tumorigenesis is origin and cell-type dependent

BRCA1 and BRCA2 mutations predispose to select cancers, yet the interplay between germline and somatic BRCA alterations in driving tumorigenesis and conferring drug sensitivity remain poorly understood. To determine which tumors are dependent on mutant BRCA, we integrated the prospective clinical sequencing of germline blood and matched tumor specimens from 17,152 advanced cancer patients with zygosity analysis, broader somatic molecular features, and treatment outcomes. Tumor lineage dictated BRCA dependence in cancers of both the 2.7% of carriers with germline pathogenic variants and the 1.8% of patients with somatic loss-of-function mutations in BRCA1 and BRCA2 across 38 affected cancer types. The rate of biallelic inactivation of mutant BRCA1/2 varied by mutational origin and tumor lineage. Consequently, BRCA-mediated phenotypes such as homologous recombination deficiency (HRD) were associated with BRCA1/2 mutations in a cell type- and zygosity-dependent manner. Phenotypic penetrance was greatest in tumors of high-risk cancer types and in tumors with biallelic inactivation of mutant BRCA, independent of its germline or somatic origin. Conversely, heterozygous BRCA mutations in other cancer types conferred no HRD phenotype. These lineage-specific differences among hallmarks of BRCA dependence also predicted differential response to PARP-inhibitor therapy. Collectively, only BRCA mutations in tumors of high BRCA penetrance had a strong selective pressure for somatic biallelic inactivation, conferred dose-dependent somatic phenotypic consequences, and PARP inhibitor sensitivity. In contrast, BRCA1/2-mutant patients with cancers not traditionally associated with BRCA susceptibility generally had tumorigenesis independent of mutant BRCA. Overall, mutant BRCA was a founding pathogenic event on which some tumors depended while in others it was likely a dispensable and biologically neutral passenger mutation unrelated to tumorigenesis. This difference was conditioned by lineage, mutational origin, and zygosity, an understanding of which requires integrated germline and somatic molecular characterization in cancer patients with implications for screening, disease pathogenesis, clinical trial design, and therapy.

Citation Format: Philip Jonsson, Michael L. Cheng, Chaitanya Bandlamudi, Preethi Srinivasan, Shweta S. Chavan, Noah D. Friedman, Ezra Y. Rosen, Allison L. Richards, Nancy Bouvier, S. Duygu Selcuklu, Craig Bielski, Wassim Abida, Ahmet Zehir, Nikolaus Schultz, Mark T. Donoghue, Jose Baselga, Kenneth Offit, Marc Ladanyi, Eileen M. O’Reilly, Howard I. Scher, Zsofia K. Stadler, Mark E. Robson, David M. Hyman, Michael F. Berger, David B. Solit, Barry S. Taylor. BRCA-mediated tumorigenesis is origin and cell-type dependent [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1752.

Prospective Evaluation of Germline Alterations in Patients With Exocrine Pancreatic Neoplasms

Background

Identification of pathogenic germline alterations (PGAs) has important clinical and therapeutic implications in pancreas cancer. We performed comprehensive germline testing (GT) in an unselected prospective cohort of patients with exocrine pancreatic neoplasms with genotype and phenotype association to facilitate identification of prognostic and/or predictive biomarkers and examine potential therapeutic implications.

Methods

Six hundred fifteen unselected patients with exocrine pancreatic neoplasms were prospectively consented for somatic tumor and matched sample profiling for 410-468 genes. GT for PGAs in 76 genes associated with cancer susceptibility was performed in an "identified" manner in 356 (57.9%) patients and in an "anonymized" manner in 259 (42.1%) patients, using an institutional review board-approved protocol. Detailed clinical and pathological features, response to platinum, and overall survival (OS) were collected for the identified cohort. OS was analyzed with Kaplan-Meier curves.

Results

PGAs were present in 122 (19.8%) of 615 patients involving 24 different genes, including BRCA1/2, ATM, PALB2, and multiple additional genes associated with the DNA damage response pathway. Of 122 patients with germline alterations, 41.8% did not meet current guidelines for GT. The difference in median OS was not statistically significant between patients with and without PGA (50.8 months, 95% confidence interval = 34.5 to not reached, two-sided P = .94). Loss of heterozygosity was found in 60.0% of BRCA1/2.

Conclusions

PGAs frequently occur in pancreas exocrine neoplasms and involve multiple genes beyond those previously associated with hereditary pancreatic cancer. These PGAs are therapeutically actionable in about 5% to 10% of patients. These data support routinely offering GT in all pancreatic ductal adenocarcimona patients with a broad panel of known hereditary cancer predisposition genes.

Pancreatic adenocarcinoma: insights into patterns of recurrence and disease behavior

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers with high metastatic potential. Clinical observations suggest that there is disease heterogeneity among patients with different sites of distant metastases, yielding distinct clinical outcomes. Herein, we investigate the impact of clinical and pathological parameters on recurrence patterns and compare survival outcomes for patients with a first site of recurrence in the liver versus lung from PDAC following original curative surgical resection.

METHODS

Using the Memorial Sloan Kettering Cancer Center ICD billing codes and tumor registry database over a 10 years period (January 2004-December 2014), we identified PDAC patients who underwent resection and subsequently presented with either liver or lung recurrence. Time from relapse to death (TRD) was calculated from date of recurrence to date of death. Using the Kaplan-Meier method, TRD was estimated and compared by recurrence site using log-rank test.

RESULTS

The median overall follow-up was 37.3 months among survivors in the entire cohort. Median TRD in this cohort was 10.7 months (95%CI: 8.9-14.6 months). Patients with first site of lung recurrence had a more favorable outcome compared to patients who recurred with liver metastasis as the first site of recurrence (median TRD of 15 versus 9 months respectively, P = 0.02). Moderate to poorly or poor differentiation was associated more often with liver than lung recurrence (40% vs 21% respectively, P = 0.047). A trend to increased lymph node metastasis in the lung recurrence cohort was observed.

CONCLUSION

PDAC patients who recur with a first site of lung metastasis have an improved clinical outcome compared to patients with first site of liver recurrence. Our data suggests there may be epidemiologic and pathologic determinants related to patterns of recurrence in PDAC.

Phase 1 trial evaluating cisplatin, gemcitabine, and veliparib in 2 patient cohorts: Germline BRCA mutation carriers and wild-type BRCA pancreatic ductal adenocarcinoma

BACKGROUND

A phase 1 trial was used to evaluate a combination of cisplatin, gemcitabine, and escalating doses of veliparib in patients with untreated advanced pancreatic ductal adenocarcinoma (PDAC) in 2 cohorts: a germline BRCA1/2-mutated (BRCA+) cohort and a wild-type BRCA (BRCA-) cohort. The aims were to determine the safety, dose-limiting toxicities (DLTs), maximum tolerated dose, and recommended phase 2 dose (RP2D) of veliparib combined with cisplatin and gemcitabine and to assess the antitumor efficacy (Response Evaluation Criteria in Solid Tumors, version 1.1) and overall survival.

METHODS

Gemcitabine and cisplatin were dosed at 600 and 25 mg/m2 , respectively, over 30 minutes on days 3 and 10 of a 21-day cycle. Four dose levels of veliparib were evaluated: 20 (dose level 0), 40 (dose level 1), and 80 mg (dose level 2) given orally twice daily on days 1 to 12 and 80 mg given twice daily on days 1 to 21 (dose level 2A [DL2A]).

RESULTS

Seventeen patients were enrolled: 9 BRCA+ patients, 7 BRCA- patients, and 1 patient with an unknown status. DLTs were reached at DL2A (80 mg twice daily on days 1 to 21). Two of the 5 patients in this cohort (40%) experienced grade 4 neutropenia and thrombocytopenia. Two grade 5 events occurred on protocol. The objective response rate in the BRCA+ cohort was 7 of 9 (77.8%). The median overall survival for BRCA+ patients was 23.3 months (95% confidence interval [CI], 3.8-30.2 months). The median overall survival for BRCA- patients was 11 months (95% CI, 1.5-12.1 months).

CONCLUSIONS

The RP2D of veliparib was 80 mg by mouth twice daily on days 1 to 12 in combination with cisplatin and gemcitabine; the DLT was myelosuppression. Substantial antitumor activity was seen in BRCA+ PDAC. A randomized phase 2 trial is currently evaluating cisplatin and gemcitabine with and without veliparib for BRCA+ PDAC (NCT01585805). Cancer 2018;124:1374-82. © 2018 American Cancer Society.

Stereotactic body radiation vs. intensity-modulated radiation for unresectable pancreatic cancer

BACKGROUND

Stereotactic body radiation therapy (SBRT) is an emerging treatment option for unresectable pancreatic cancer, and is postulated to be more effective and less toxic than conventionally fractionated intensity modulated radiation therapy (IMRT).

MATERIAL AND METHODS

We retrospectively reviewed unresectable stage I-III pancreatic adenocarcinoma treated from 2008 to 2016 at our institution with SBRT (five fractions, 30-33 Gy) or IMRT (25-28 fractions, 45-56 Gy with concurrent chemotherapy). Groups were compared with respect to overall survival (OS), local and distant failure, and toxicity. Log-rank test and Cox proportional hazards regression model, and competing risks methods were used for univariate and multivariate analysis.

RESULTS

SBRT patients (n = 44) were older than IMRT (n = 226) patients; otherwise there was no significant difference in baseline characteristics. There was no significant difference in OS or local or distant failure. There was no significant difference in rates of subsequent resection (IMRT =17%, SBRT =7%, p = .11). IMRT was associated with more acute grade 2+ gastrointestinal toxicity, grade 2+ fatigue, and grade 3+ hematologic toxicity (p = .008, p < .0001, p = .001, respectively).

CONCLUSIONS

In this analysis, SBRT achieves similar disease control outcomes as IMRT, with less acute toxicity. This suggests SBRT is an attractive technique for pancreatic radiotherapy because of improved convenience and tolerability with equivalent efficacy. However, the lack of observed advantages in disease control with this moderate-dose SBRT regimen may suggest a role for increasing SBRT dose, if this can be accomplished without significant increase in toxicity.

Neoadjuvant treatment of pancreatic adenocarcinoma: a systematic review and meta-analysis of 5520 patients

BACKGROUND

Recent years have seen standardization of the anatomic definitions of pancreatic adenocarcinoma, and increasing utilization of neoadjuvant therapy (NAT). The aim of the current review was to summarize the evidence for NAT in pancreatic adenocarcinoma since 2009, when consensus criteria for resectable (R), borderline resectable (BR), and locally advanced (LA) disease were endorsed.

METHODS

PubMed search was undertaken along with extensive backward search of the references of published articles to identify studies utilizing NAT for pancreatic adenocarcinoma. Abstracts from ASCO-GI 2014 and 2015 were also searched.

RESULTS

A total of 96 studies including 5520 patients were included in the final quantitative synthesis. Pooled estimates revealed 36% grade ≥ 3 toxicities, 5% biliary complications, 21% hospitalization rate and low mortality (0%, range 0-16%) during NAT. The majority of patients (59%) had stable disease. On an intention-to-treat basis, R0-resection rates varied from 63% among R patients to 23% among LA patients. R0 rates were > 80% among all patients who were resected after NAT. Among R and BR patients who underwent resection after NAT, median OS was 30 and 27.4 months, respectively.

CONCLUSIONS

The current study summarizes the recent literature for NAT in pancreatic adenocarcinoma and demonstrates improving outcomes after NAT compared to those historically associated with a surgery-first approach for pancreatic adenocarcinoma.

Chemotherapy and intensity-modulated radiation therapy for locally advanced pancreatic cancer achieves a high rate of R0 resection

BACKGROUND

To assess local control, survival and conversion to resectability among locally advanced pancreatic cancer (LAPC) patients treated with induction chemotherapy (ICT) followed by chemoradiotherapy treatment using intensity-modulated radiation therapy (IMRT).

MATERIAL AND METHODS

Between 2007 and 2012, 134 LAPC patients were treated with ICT followed by IMRT. After chemoradiotherapy, 40 patients received maintenance chemotherapy.

RESULTS

With a median follow-up of 20 months, median overall survival (OS) was 23 months. One- and two-year OS was 85% and 47%, respectively. On multivariate analysis, progression of disease after IMRT was associated with worse OS. Cumulative incidence of local failure was 10% at one year and 36% at two years. Twenty-six patients (19%) underwent resection after chemoradiotherapy including 22 patients (85%) with negative margins. On multivariate analysis, response to IMRT was associated with surgery (p = .01). Acute grade 3-4 hematologic and non-hematologic toxicity rates were 26% and 4.5%, respectively.

CONCLUSION

IMRT is safe in patients with LAPC. Patients with non-progressive LAPC after ICT and who received IMRT had high rates of local control and prolonged survival.

Genomic instability in pancreatic adenocarcinoma: a new step towards precision medicine and novel therapeutic approaches

Pancreatic cancer is one of the most challenging cancers. Whole genome sequencing studies have been conducted to elucidate the underlying fundamentals underscoring disease behavior. Studies have identified a subgroup of pancreatic cancer patients with distinct molecular and clinical features. Genetic fingerprinting of these tumors is consistent with an unstable genome and defective DNA repair pathways, which creates unique susceptibility to agents inducing DNA damage. BRCA1/2 mutations, both germline and somatic, which lead to impaired DNA repair, are found to be important biomarkers of genomic instability as well as of response to DNA damaging agents. Recent studies have elucidated that PARP inhibitors and platinum agents may be effective to induce tumor regression in solid tumors bearing an unstable genome including pancreatic cancer. In this review we discuss the characteristics of genomic instability in pancreatic cancer along with its clinical implications and the utility of DNA targeting agents particularly PARP inhibitors as a novel treatment approach.

Abstract CT026: Phase I trial of HuMab-5B1 (MVT-5873), a novel monoclonal antibody targeting sLea, in patients with advanced pancreatic cancer and other CA19-9 positive malignancies

MVT-5873 (HuMab-5B1) is a fully human, IgG1 antibody targeting sialyl Lewis A (sLea), an epitope present on CA19-9. MVT-5873 was discovered from lymphocytes from a breast cancer patient immunized with a sLea-KLH vaccine. CA19-9 is widely expressed in pancreatic and other gastrointestinal tract cancers, where it plays a key role in tumor adhesion and metastatic potential and is a recognized marker of an aggressive phenotype.

MVT-5873 binds with high affinity and exquisite specificity to the sLea antigen epitope in a glycan microarray panel. MVT-5873 selectively binds to CA19-9 expressed on human tumor cell lines and induces cytotoxicity through antibody dependent cell-mediated and complement-dependent mechanisms. MVT-5873 has activity as both a single agent and in combination with chemotherapy in murine xenograft models of human pancreatic, colon, and small cell lung cancers. MVT-5873 appears to potentiate the activity of paclitaxel and of gemcitabine/nab-paclitaxel in a dose-dependent fashion in DMS-79 and BxPC3 xenograft models, respectively.

A first-in-human clinical trial of MVT-5873 opened January 2016. The trial is a Phase 1, open label, multicenter, non-randomized, dose escalation/expansion trial of MVT-5873 as a single agent (Group A) and in combination with conventional nab-paclitaxel/gemcitabine (Group B). Dose escalation uses a standard 3+3 design followed by expansion at MTD in 10 subjects..

Primary endpoints include 1) single-agent and combination MTD, 2) determination of the safety profile, and 3) pharmacokinetics. Secondary endpoints include 1) response rate, and 2) duration of response. Exploratory endpoints include 1) development of anti-MVT-5873 antibodies, 2) relationships between circulating CA19-9 levels and tumor response, 3) relationships between tumor IHC expression and circulating levels of CA19-9, 4) relationships between circulating CA19-9 levels and MVT-5873 pharmacokinetics (PK).

Key inclusion criteria:

• Histologically confirmed, progressive, locally-advanced or metastatic pancreatic ductal adenocarcinoma or other CA19-9 positive malignancies

• Evaluable or measurable disease

• ECOG PS of 0 or 1

• Adequate hematologic, hepatic, and renal function

• Measurable disease

• Serum CA19-9 levels ? 37 U/mL or CA19-9 positive tumor by IHC

Key exclusion criteria:

• Brain metastases unless treated and well controlled for at least 3 months

• Other active cancer likely to require treatment in the next 2 years

• Fewer than 28 days from prior anticancer therapy except for ongoing hormonal therapy administered for control of prostate cancer

• Significant cardiovascular risk

The results will be summarized with descriptive statistics. PK of MVT-5873 will be evaluated using non-compartmental methods.

Citation Format: Eileen M. O’Reilly, Todd M. Bauer, Jeffrey Infante, John C. Gutheil, Pamela Klein, Kenneth H. Yu, Maeve A. Lowery, Phil Livingston, Pricilla Martin, Wolfgang Scholz, Paul W. Maffuid. Phase I trial of HuMab-5B1 (MVT-5873), a novel monoclonal antibody targeting sLea, in patients with advanced pancreatic cancer and other CA19-9 positive malignancies. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr CT026.

Genetic Diversity of Pancreatic Ductal Adenocarcinoma and Opportunities for Precision Medicine

Patients with pancreatic ductal adenocarcinoma (PDA) have a poor prognosis despite new treatments; approximately 7% survive for 5 years. Although there have been advances in systemic, primarily cytotoxic, therapies, it has been a challenge to treat patients with PDA using targeted therapies. Sequence analyses have provided a wealth of information about the genetic features of PDA and have identified potential therapeutic targets. Preclinical and early-phase clinical studies have found specific pathways could be rationally targeted; it might also be possible to take advantage of the genetic diversity of PDAs to develop therapeutic agents. The genetic diversity and instability of PDA cells have long been thought of as obstacles to treatment, but are now considered exploitable features. We review the latest findings in pancreatic cancer genetics and the promise of targeted approaches in PDA therapy.

A novel survival-based tissue microarray of pancreatic cancer validates MUC1 and mesothelin as biomarkers

BACKGROUND

One-fifth of patients with seemingly 'curable' pancreatic ductal adenocarcinoma (PDA) experience an early recurrence and death, receiving no definable benefit from a major operation. Some patients with advanced stage tumors are deemed 'unresectable' by conventional staging criteria (e.g. liver metastasis), yet progress slowly. Effective biomarkers that stratify PDA based on biologic behavior are needed. To help researchers sort through the maze of biomarker data, a compendium of ∼2500 published candidate biomarkers in PDA was compiled (PLoS Med, 2009. 6(4) p. e1000046).

METHODS AND FINDINGS

Building on this compendium, we constructed a survival tissue microarray (termed s-TMA) comprised of short-term (cancer-specific death <12 months, n = 58) and long-term survivors (>30 months, n = 79) who underwent resection for PDA (total, n = 137). The s-TMA functions as a biological filter to identify bona fide prognostic markers associated with survival group extremes (at least 18 months separate survival groups). Based on a stringent selection process, 13 putative PDA biomarkers were identified from the public biomarker repository. Candidates were tested against the s-TMA by immunohistochemistry to identify the best markers of tumor biology. In a multivariate model, MUC1 (odds ratio, OR = 28.95, 3+ vs. negative expression, p = 0.004) and MSLN (OR = 12.47, 3+ vs. negative expression, p = 0.01) were highly predictive of early cancer-specific death. By comparison, pathologic factors (size, lymph node metastases, resection margin status, and grade) had ORs below three, and none reached statistical significance. ROC curves were used to compare the four pathologic prognostic features (ROC area = 0.70) to three univariate molecular predictors (MUC1, MSLN, MUC2) of survival group (ROC area = 0.80, p = 0.07).

CONCLUSIONS

MUC1 and MSLN were superior to pathologic features and other putative biomarkers as predicting survival group. Molecular assays comparing cancers from short and long survivors are an effective strategy to screen biomarkers and prioritize candidate cancer genes for diagnostic and therapeutic studies.