Results of a Randomized, Double-Blind, Placebo-Controlled, Phase 1b/2 Trial of Nabpaclitaxel + Gemcitabine ± Olaratumab in Treatment-Naïve Participants with Metastatic Pancreatic Cancer

The efficacy and safety of olaratumab plus nabpaclitaxel and gemcitabine in treatment-naïve participants with metastatic pancreatic ductal adenocarcinoma was evaluated. An initial phase 1b dose-escalation trial was conducted to determine the olaratumab dose for the phase 2 trial, a randomized, double-blind, placebo-controlled trial to compare overall survival (OS) in the olaratumab arm vs. placebo arms. In phase 1b, 22 participants received olaratumab at doses of 15 and 20 mg/kg with a fixed dose of nabpaclitaxel and gemcitabine. In phase 2, 159 participants were randomized to receive olaratumab 20 mg/kg in cycle 1 followed by 15 mg/kg in the subsequent cycles (n = 81) or the placebo (n = 78) on days 1, 8, and 15 of a 28-day cycle, plus nabpaclitaxel and gemcitabine. The primary objective of the trial was not met, with a median OS of 9.1 vs. 10.8 months (hazard ratio [HR] = 1.05; 95% confidence interval [CI]: 0.728, 1.527; p = 0.79) and the median progression-free survival (PFS) was 5.5 vs. 6.4 months (HR = 1.19; 95% CI: 0.806, 1.764; p = 0.38), in the olaratumab vs. placebo arms, respectively. The most common treatment-emergent adverse event of any grade across both arms was fatigue. Olaratumab plus chemotherapy failed to improve the OS or PFS in participants with metastatic PDAC. There were no new safety signals.

Elucidating the Heterogeneity of Immunotherapy Response and Immune-Related Toxicities by Longitudinal ctDNA and Immune Cell Compartment Tracking in Lung Cancer

PURPOSE

Although immunotherapy is the mainstay of therapy for advanced non-small cell lung cancer (NSCLC), robust biomarkers of clinical response are lacking. The heterogeneity of clinical responses together with the limited value of radiographic response assessments to timely and accurately predict therapeutic effect-especially in the setting of stable disease-calls for the development of molecularly informed real-time minimally invasive approaches. In addition to capturing tumor regression, liquid biopsies may be informative in capturing immune-related adverse events (irAE).

EXPERIMENTAL DESIGN

We investigated longitudinal changes in circulating tumor DNA (ctDNA) in patients with metastatic NSCLC who received immunotherapy-based regimens. Using ctDNA targeted error-correction sequencing together with matched sequencing of white blood cells and tumor tissue, we tracked serial changes in cell-free tumor load (cfTL) and determined molecular response. Peripheral T-cell repertoire dynamics were serially assessed and evaluated together with plasma protein expression profiles.

RESULTS

Molecular response, defined as complete clearance of cfTL, was significantly associated with progression-free (log-rank P = 0.0003) and overall survival (log-rank P = 0.01) and was particularly informative in capturing differential survival outcomes among patients with radiographically stable disease. For patients who developed irAEs, on-treatment peripheral blood T-cell repertoire reshaping, assessed by significant T-cell receptor (TCR) clonotypic expansions and regressions, was identified on average 5 months prior to clinical diagnosis of an irAE.

CONCLUSIONS

Molecular responses assist with the interpretation of heterogeneous clinical responses, especially for patients with stable disease. Our complementary assessment of the peripheral tumor and immune compartments provides an approach for monitoring of clinical benefits and irAEs during immunotherapy.

Impact of Recombinant Granulocyte Colony-Stimulating Factor During Neoadjuvant Therapy on Outcomes of Resected Pancreatic Cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease characterized by chronic inflammation and a tolerogenic immune response. The granulocyte colony-stimulating factor (G-CSF)-neutrophil axis promotes oncogenesis and progression of PDAC. Despite frequent use of recombinant G-CSF in the management and prevention of chemotherapy-induced neutropenia, its impact on oncologic outcomes of patients with resected PDAC is unclear.

PATIENTS AND METHODS

This cohort study assessing the impact of G-CSF administration was conducted on 351 patients with PDAC treated with neoadjuvant therapy (NAT) and pancreatic resection at a high-volume tertiary care academic center from 2014 to 2019. Participants were identified from a prospectively maintained database and had a median follow-up of 45.8 months.

RESULTS

Patients receiving G-CSF (n=138; 39.3%) were younger (64.0 vs 66.7 years; P=.008), had lower body mass index (26.5 vs 27.9; P=.021), and were more likely to receive 5-FU-based chemotherapy (42.0% vs 28.2%; P<.0001). No differences were observed in baseline or clinical tumor staging. Patients receiving G-CSF were more likely to have an elevated (>5.53) post-NAT neutrophil-to-lymphocyte ratio (45.0% vs 29.6%; P=.004). G-CSF recipients also demonstrated higher circulating levels of neutrophil extracellular traps (+709 vs -619 pg/mL; P=.006). On multivariate analysis, G-CSF treatment was associated with perineural invasion (hazard ratio [HR], 2.65; 95% CI, 1.16-6.03; P=.021) and margin-positive resection (HR, 1.67; 95% CI, 1.01-2.77; P=.046). Patients receiving G-CSF had decreased overall survival (OS) compared with nonrecipients (median OS, 29.2 vs 38.7 months; P=.001). G-CSF administration was a negative independent predictor of OS (HR, 2.02; 95% CI, 1.45-2.79; P<.0001). In the inverse probability weighted analysis of 301 matched patients, neoadjuvant G-CSF administration was associated with reduced OS.

CONCLUSIONS

In patients with localized PDAC receiving NAT prior to surgical extirpation, G-CSF administration may be associated with worse oncologic outcomes and should be further evaluated.

Defining the Values and Quality of Life of Cancer Survivors Following Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: An International Survey Study

BACKGROUND

Advances in treatment of peritoneal surface malignancies including cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS±HIPEC) have led to long-term survivorship, yet the subsequent quality of life (QOL) and values of these patients are unknown.

PATIENTS AND METHODS

Survivors were offered surveys via online support groups. Novel items assessed how patients prioritized experience, costs, longevity, and wellbeing.

RESULTS

Of the 453 gastrointestinal/hepatobiliary (GI/HPB) surgical patients that responded, 74 underwent CRS±HIPEC and were 54±12 years old, 87% female, and 93% white. Respondents averaged 29 months from diagnosis, with a maximum survival of 20 years. With a moderate level of agreement (W = 39%), rankings of value metrics among respondents were predictable (p < 0.001). Longevity and functional independence were ranked highest; treatment experience and cost of treatment were ranked lowest (p < 0.001). Those who underwent CRS±HIPEC or other GI/HPB surgeries reported the same rank order. QOL in CRS±HIPEC survivors, both mental (M-QOL) (44±13) and physical (P-QOL) (41±11) were lower than in the general population (50±10); p < 0.001. Impairments persisted throughout survivorship, but M-QOL improved over time (p < 0.05). When comparing CRS±HIPEC with other GI/HPB cancer surgery survivors, M-QOL (43±13 versus 43±14, p = 0.85) and P-QOL (40±11 versus 42±12, p = 0.41) were similar.

CONCLUSIONS

Although CRS±HIPEC survivors experience long-term mental and physical health impairments, they were similar to those experienced by survivors of other GI/HPB cancer surgeries, and their QOL improved significantly throughout survivorship. As CRS±HIPEC survivors prioritize longevity above all other metrics, survival benefit may outweigh a temporary reduction in QOL.

Treatment Response in First-Line Metastatic Pancreatic Ductal Adenocarcinoma Is Stratified By a Composite Index of Tumor Proliferation and CD8 T-Cell Infiltration

PURPOSE

Determinants of treatment outcomes to chemotherapy-based regimens in metastatic pancreatic ductal adenocarcinoma (PDA) remain ill-defined. Our aim was to examine tissue-based correlates of treatment response and resistance using matched baseline and on-treatment biopsies collected from patients with PDA treated in the first-line metastatic setting.

EXPERIMENTAL DESIGN

Patients with treatment-naïve metastatic PDA were enrolled in a Phase II trial (NCT02077881) investigating gemcitabine plus nab-paclitaxel in combination with indoximod, an orally administered small-molecule inhibitor of the IDO pathway. Baseline and on-treatment biopsies (week 8) of metastatic lesions (88% liver) were collected from a cohort of responders (N = 8) and non-responders (N = 8) based on RECIST v1.1 and examined by multiplex IHC and mRNA sequencing.

RESULTS

Treatment altered the transcriptional profile of metastatic lesions with a decrease in tumor cell proliferation independent of treatment response. The antiproliferative response was seen in both basal and classical PDA subtypes. PDA subtype was not associated with survival outcomes; instead, genes involved in immune activation distinguished responders from non-responders. Tumor response was associated with an increase in CD3+ and CD8+ T-cell infiltrates into metastatic lesions. A composite of decreased tumor proliferation in response to treatment and increased CD8 T-cell infiltration in metastatic lesions identified responders and associated with a favorable survival outcome.

CONCLUSIONS

Our findings suggest that inhibiting cancer cell proliferation alone in PDA is insufficient to produce tumor responses and support a role for tumor-extrinsic mechanisms, such as CD8+ T cells, which combine with the cancer cell proliferation index to define treatment outcomes.

Avelumab or talazoparib in combination with binimetinib in metastatic pancreatic ductal adenocarcinoma: dose-finding results from phase Ib of the JAVELIN PARP MEKi trial

BACKGROUND

Combinations of avelumab [anti-programmed death-ligand 1 (anti-PD-L1)] or talazoparib [poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor] with binimetinib (MEK inhibitor) were expected to result in additive or synergistic antitumor activity relative to each drug administered alone. Here, we report phase Ib results from JAVELIN PARP MEKi, which investigated avelumab or talazoparib combined with binimetinib in metastatic pancreatic ductal adenocarcinoma (mPDAC).

PATIENTS AND METHODS

Patients with mPDAC that had progressed with prior treatment received avelumab 800 mg every 2 weeks plus binimetinib 45 mg or 30 mg two times daily (continuous), or talazoparib 0.75 mg daily plus binimetinib 45 mg or 30 mg two times daily (7 days on/7 days off). The primary endpoint was dose-limiting toxicity (DLT).

RESULTS

A total of 22 patients received avelumab plus binimetinib 45 mg (n = 12) or 30 mg (n = 10). Among DLT-evaluable patients, DLT occurred in five of 11 patients (45.5%) at the 45-mg dose, necessitating de-escalation to 30 mg; DLT occurred in three of 10 patients (30.0%) at the 30-mg dose. Among patients treated at the 45-mg dose, one (8.3%) had a best overall response of partial response. Thirteen patients received talazoparib plus binimetinib 45 mg (n = 6) or 30 mg (n = 7). Among DLT-evaluable patients, DLT occurred in two of five patients (40.0%) at the 45-mg dose, necessitating de-escalation to 30 mg; DLT occurred in two of six patients (33.3%) at the 30-mg dose. No objective responses were observed.

CONCLUSIONS

Combinations of avelumab or talazoparib plus binimetinib resulted in higher-than-expected DLT rates. However, most DLTs were single occurrences, and the overall safety profiles were generally consistent with those reported for the single agents.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.govNCT03637491; https://clinicaltrials.gov/ct2/show/NCT03637491.

Safety and Activity of Immune Checkpoint Inhibitors in People Living With HIV and Cancer: A Real-World Report From the Cancer Therapy Using Checkpoint Inhibitors in People Living With HIV-International (CATCH-IT) Consortium

PURPOSE

Compared with people living without HIV (PWOH), people living with HIV (PWH) and cancer have traditionally been excluded from immune checkpoint inhibitor (ICI) trials. Furthermore, there is a paucity of real-world data on the use of ICIs in PWH and cancer.

METHODS

This retrospective study included PWH treated with anti-PD-1- or anti-PD-L1-based therapies for advanced cancers. Kaplan-Meier method was used to estimate overall survival (OS) and progression-free survival (PFS). Objective response rates (ORRs) were measured per RECIST 1.1 or other tumor-specific criteria, whenever feasible. Restricted mean survival time (RMST) was used to compare OS and PFS between matched PWH and PWOH with metastatic NSCLC (mNSCLC).

RESULTS

Among 390 PWH, median age was 58 years, 85% (n = 331) were males, 36% (n = 138) were Black; 70% (n = 274) received anti-PD-1/anti-PD-L1 monotherapy. Most common cancers were NSCLC (28%, n = 111), hepatocellular carcinoma ([HCC]; 11%, n = 44), and head and neck squamous cell carcinoma (HNSCC; 10%, n = 39). Seventy percent (152/216) had CD4+ T cell counts ≥200 cells/µL, and 94% (179/190) had HIV viral load <400 copies/mL. Twenty percent (79/390) had any grade immune-related adverse events (irAEs) and 7.7% (30/390) had grade ≥3 irAEs. ORRs were 69% (nonmelanoma skin cancer), 31% (NSCLC), 16% (HCC), and 11% (HNSCC). In the matched mNSCLC cohort (61 PWH v 110 PWOH), 20% (12/61) PWH and 22% (24/110) PWOH had irAEs. Adjusted 42-month RMST difference was -0.06 months (95% CI, -5.49 to 5.37; P = .98) for PFS and 2.23 months (95% CI, -4.02 to 8.48; P = .48) for OS.

CONCLUSION

Among PWH, ICIs demonstrated differential activity across cancer types with no excess toxicity. Safety and activity of ICIs were similar between matched cohorts of PWH and PWOH with mNSCLC.

The use of angiotensin system inhibitors correlates with longer survival in resected pancreatic adenocarcinoma patients

BACKGROUND

Activities and inhibition of the Renin-Angiotensin-Aldosterone System (RAAS) may affect the survival of resected pancreatic ductal adenocarcinoma (PDAC) patients METHOD: A single-institution retrospective analysis of resected PDAC patients between 2010 and 2019. To estimate the effect of angiotensin system inhibitors (ASIs) on patient survival, we performed Kaplan Meier analysis, Cox Proportional Hazards model, Propensity Score Matching (PSM), and inverse probability weighting (IPW) analysis.

RESULTS

742 patients were included in the analysis. The average age was 67.0 years, with a median follow-up of 24.1 months. The use of ASI was associated with significantly longer overall survival in univariate (p = 0.004) and multivariable (HR = 0.70 [0.56-0.88],p = 0.003) adjusted analysis. In a propensity score-matched cohort of 400 patients, ASI use was again associated with longer overall survival (p = 0.039). Lastly, inverse probability weighting (IPW) analysis suggested that the use of ASI was associated with an average treatment effect on the treated (ATT) of HR = 0.68 [0.53-0.86],p = 0.002) for overall survival.

CONCLUSION

In this single-institution retrospective study focusing on resected PDAC patients, the use of ASI was associated with longer overall survival in multiple statistical models. Prospective clinical trials are needed before routine clinical implementation of ASI as an adjuvant to existing therapy can be recommended.

No survival benefit with suboptimal CA19-9 response: defining effective neoadjuvant chemotherapy in resectable or borderline resectable pancreatic cancer

BACKGROUND/PURPOSE

Neoadjuvant chemotherapy (NAC) is gaining popularity over a surgery-first (SF) approach in treating resectable and borderline resectable pancreatic ductal adenocarcinoma (PDAC). However, what constitutes effective neoadjuvant chemotherapy is unknown.

METHODS

We retrospectively analyzed resectable and borderline resectable PDAC patients who underwent pancreaticoduodenectomy (2010-2019) at a single institution. Optimal CA19-9 response was defined as normalization AND >50% reduction. We utilized Kaplan-Meier and multivariable-adjusted Cox models and competing risk subdistribution methods for statistical analysis.

RESULTS

586 patients were included in this study. The multivariable-adjusted analysis demonstrated OS benefit in the NAC group only when OS was calculated from diagnosis (HR = 0.72, p = 0.02), but not from surgery (HR = 0.81, p = 0.1). However, in 59 patients who achieved optimal CA19-9 response, OS is significantly longer than the 134 patients with suboptimal CA19-9 response (39.3 m vs. 21.5 m, p = 0.005) or the 117 SF patients (39.3 m vs. 19.5 m, p < 0.001). Notably, a suboptimal CA19-9 response conferred no OS advantage compared to SF patients. The accumulative incidence of liver metastases (but not other metastases) was significantly reduced only in patients with optimal CA19-9 response to NAC (multivariable-adjusted subdistribution HR = 0.26, p = 0.03).

CONCLUSION

CA19-9 response to NAC may serve as the marker for effective NAC. These findings warrant validation in a multi-institutional study.

Evaluation of Adjuvant Chemotherapy Survival Outcomes Among Patients With Surgically Resected Pancreatic Carcinoma With Node-Negative Disease After Neoadjuvant Therapy

Importance

Neoadjuvant therapy (NAT) is rarely associated with a complete histopathologic response in patients with pancreatic ductal adenocarcinoma (PDAC) but results in downstaging of regional nodal disease. Such nodal downstaging after NAT may have implications for the use of additional adjuvant therapy (AT).

Objectives

To examine the prognostic implications of AT in patients with node-negative (N0) disease after NAT and to identify factors associated with progression-free (PFS) and overall survival (OS).

Design, Setting, and Participants

A retrospective review was conducted using data from 2 high-volume, tertiary care academic centers (University of Pittsburgh Medical Center and the Medical College of Wisconsin). Prospectively maintained pancreatic cancer databases at both institutes were searched to identify patients with localized PDAC treated with preoperative therapy and subsequent surgical resection between 2010 and 2019, with N0 disease on final histopathology.

Exposures

Patients received NAT consisting of chemotherapy with or without concomitant neoadjuvant radiation (NART). For patients who received NART, chemotherapy regimens were gemcitabine or 5-fluoururacil based and included stereotactic body radiotherapy (SBRT) or intensity-modulated radiation therapy (IMRT) after all intended chemotherapy and approximately 4 to 5 weeks before anticipated surgery. Adjuvant therapy consisted of gemcitabine-based therapy or FOLFIRINOX; when used, adjuvant radiation was commonly administered as either SBRT or IMRT.

Main Outcomes and Measures

The association of AT with PFS and OS was evaluated in the overall cohort and in different subgroups. The interaction between AT and other clinicopathologic variables was examined on Cox proportional hazards regression analysis.

Results

In this cohort study, 430 consecutive patients were treated between 2010 and 2019. Patients had a mean (SD) age of 65.2 (9.4) years, and 220 (51.2%) were women. The predominant NAT was gemcitabine based (196 patients [45.6%]), with a median duration of 2.7 cycles (IQR, 1.5-3.4). Neoadjuvant radiation was administered to 279 patients (64.9%). Pancreatoduodenectomy was performed in 310 patients (72.1%), and 160 (37.2%) required concomitant vascular resection. The median lymph node yield was 26 (IQR, 19-34); perineural invasion (PNI), lymphovascular invasion (LVI), and residual positive margins (R1) were found in 254 (59.3%), 92 (22.0%), and 87 (21.1%) patients, respectively. The restricted mean OS was 5.2 years (95% CI, 4.8-5.7). On adjusted analysis, PNI, LVI, and poorly differentiated tumors were independently associated with worse PFS and OS in N0 disease after NAT, with hazard ratios (95% CIs) of 2.04 (1.43-2.92; P < .001) and 1.68 (1.14-2.48; P = .009), 1.47 (1.08-1.98; P = .01) and 1.54 (1.10-2.14; P = .01), and 1.90 (1.18-3.07; P = .008) and 1.98 (1.20-3.26; P = .008), respectively. Although AT was associated with prolonged survival in the overall cohort, the effect was reduced in patients who received NART and strengthened in patients with PNI (AT × PNI interaction: hazard ratio, 0.55 [95% CI, 0.32-0.97]; P = .04).

Conclusions and Relevance

The findings of this cohort study suggest a survival benefit for AT in patients with N0 disease after NAT and surgical resection. This survival benefit may be most pronounced in patients with PNI.

Neoadjuvant Therapy Versus Upfront Resection for Nonpancreatic Periampullary Adenocarcinoma

BACKGROUND

In contrast to pancreatic ductal adenocarcinoma (PDAC), neoadjuvant therapy (NAT) for periampullary adenocarcinomas is not well studied, with data limited to single-institution retrospective reviews with small cohorts. We sought to compare outcomes of NAT versus upfront resection (UR) for non-PDAC periampullary adenocarcinomas.

PATIENTS AND METHODS

Using the National Cancer Database (NCDB), we identified patients who underwent surgery for extrahepatic cholangiocarcinoma, ampullary adenocarcinoma, or duodenal adenocarcinoma from 2006 to 2016. We compared outcomes between NAT versus UR groups for each tumor subtype with 1:3 propensity score matching. Cox regression was used to identify predictors of survival.

RESULTS

Among 7656 patients who underwent resection for non-PDAC periampullary adenocarcinoma, the proportion of patients who received NAT increased from 6 to 11% for cholangiocarcinoma (p < 0.01), 1 to 4% for ampullary adenocarcinoma (p = 0.01), and 5 to 8% for duodenal adenocarcinoma (p = 0.08). Length of stay, readmission, and 30-day mortality were comparable between NAT and UR. All tumor subtypes were downstaged following NAT (p < 0.01). The R0 resection rate was significantly higher in patients with extrahepatic cholangiocarcinoma who received NAT, and these patients had improved median overall survival (38 vs 26 months, p < 0.001). After adjustment for clinicopathologic factors and adjuvant chemotherapy, use of NAT was associated with improved survival in patients with cholangiocarcinoma [hazard ratio (HR) 0.69, 95% confidence interval (CI) 0.54-0.89, p = 0.004] but not duodenal or ampullary adenocarcinoma. The survival advantage for cholangiocarcinoma persisted after propensity matching.

CONCLUSION

This national cohort analysis suggests, for the first time, that neoadjuvant therapy is associated with improved survival in patients with extrahepatic cholangiocarcinoma.

A study of relacorilant in combination with nab-paclitaxel in patients with metastatic pancreatic ductal adenocarcinoma

4140

Background: Pancreatic cancer remains the third-leading cause of cancer-related death in the US. Average overall survival is only one year, and no standard therapies exist beyond second line. Chemotherapy resistance is one reason for the poor outcomes in pancreatic cancer, which can be caused by, among other factors, excess tumor expression of the glucocorticoid receptor (GR). Nonclinical and clinical data indicate that GR antagonism may enhance or restore chemotherapy sensitivity. Here, we report the interim analysis of RELIANT, a trial evaluating the efficacy and safety of relacorilant, a selective GR modulator, with nab-paclitaxel in patients with metastatic pancreatic ductal adenocarcinoma (mPDAC). Methods: RELIANT (NCT04329949) was a single-arm, open-label, multicenter study of relacorilant (100 mg QD) + nab-paclitaxel (80 mg/m2 on days 1, 8, and 15 of each 28-day cycle) in patients with histologically confirmed mPDAC. Based on tolerability, relacorilant doses were escalated up to 150 mg. Patients with 2+ prior lines of therapy, including prior gemcitabine- and fluoropyrimidine-based therapy, were enrolled. Planned enrollment was 80 patients. The study included a planned interim analysis after approximately 40 patients had completed 12 weeks of treatment or discontinued study treatment due to disease progression or toxicity. Objective response rate (ORR) by blinded independent central review was the primary endpoint. At the interim analysis, ORR was assessed by the investigator. Results: At the interim analysis, 43 heavily pretreated patients with a median age of 64 years (range: 43–78; 56% male) had been enrolled. 27/43 (63%) patients had received ≥2 prior lines of therapy (range: 2–5), and all but 3 patients had received prior treatment with nab-paclitaxel. Twelve patients (28%) did not have a post-baseline radiographic tumor assessment and were hence not efficacy evaluable. Most common reasons for discontinuation from relacorilant were disease progression (n = 16), adverse event (AE, n = 8), and patient decision (n = 9). Relacorilant + nab-paclitaxel demonstrated antitumor activity with 15/43 (35%) patients showing decreases in target lesion size, 10/43 (23%) achieving disease control for at least 12 weeks, and 17/43 (40%) having decreases in CA 19-9. Of note, one patient has been on study treatment for > 15 months. No confirmed responses by RECIST (CR or PR) were observed, and enrollment was thus stopped after the interim analysis. No new safety signals were identified. The most common AEs were fatigue, nausea, and decreased appetite. Suppression of GR target genes was also observed. Conclusions: Modest antitumor activity of relacorilant + nab-paclitaxel was observed in this heavily pretreated patient population, with a safety profile similar to that observed for relacorilant in other oncology studies. Clinical trial information: NCT04329949.

Phase 3, multicenter, randomized study of CPI-613 with modified FOLFIRINOX (mFFX) versus FOLFIRINOX (FFX) as first-line therapy for patients with metastatic adenocarcinoma of the pancreas (AVENGER500)

4023

Background: Metastatic pancreatic cancer (mPC) remains a deadly disease with very limited treatment options. FFX is a standard first-line therapy for mPC with a median overall survival (mOS) of 11.1 months. CPI-613 is a stable intermediate of a lipoate analog that inhibits pyruvate dehydrogenase and α-ketoglutarate dehydrogenase enzymes of the tricarboxylic cycle preferentially within the mitochondria of cancer cells. In a phase I study, CPI-613+mFFX was safe and exhibited promising signal of efficacy. Methods: A global, randomized phase 3 trial was conducted across 73 sites to investigate the efficacy and safety of CPI-613 in combination with mFFX compared to standard dose FFX in treatment-naïve patients with mPC. Treatment was administered in 2-weekly cycles until progression or intolerable toxicity. In the experimental arm, CPI-613 at 500 mg/m2 was given intravenously on days 1 and 3. The doses of irinotecan, oxaliplatin, and 5-fluorouracil in the experimental arm were 65 mg/m2, 140 mg/m2, and 2,400 mg/2, respectively. Primary endpoint was OS. Secondary endpoints were progression-free survival (PFS), overall response rate (ORR), duration of response, pharmacokinetics, patient reported outcomes and safety. Results: 528 patients were randomly assigned (266 in test and 262 in control arm). There were 362 deaths, with a mOS of 11.1 months for CPI-613+mFFX vs. 11.7 months for FFX [hazard ratio (HR), 0.95; 95% CI, 0.77 to 1.18; P = 0.655]; mPFS was 7.8 months vs. 8.0 months respectively [HR, 0.99; 95% CI, 0.76 to 1.29; P = 0.94]; ORR was 39% in the test arm vs. 34% in the control arm [ORR ratio, 1.23 (95% CI, 0.86 to 1.75)]. Grade ≥ 3 treatment-emergent adverse events with ≥ 10% frequency in CPI-613 plus mFFX vs. FFX arm were diarrhea (11.2% vs. 19.6%), hypokalemia (13.1% vs. 14.9%), anemia (13.9% vs. 13.6%), neutropenia (11.2% vs. 14.0%), thrombocytopenia (11.6% vs. 13.6%) and fatigue (10.8% vs. 11.5%). Conclusions: The addition of CPI-613 to mFFX failed to show significant improvements of ORR, PFS or OS. The mFFX in the test arm that had the lowest prospectively tested doses of FFX was without compromise on PFS or OS and may be considered as a reference for future FFX administration. Clinical trial information: NCT03504423.

Adaptive Dynamic Therapy and Survivorship for Operable Pancreatic Cancer

Importance

Neoadjuvant therapy is increasingly used in localized pancreatic carcinoma, and survival is correlated with carbohydrate antigen 19-9 (CA19-9) levels and histopathologic response following neoadjuvant therapy. With several regimens now available, the choice of chemotherapy could be best dictated by response to neoadjuvant therapy (as measured by CA19-9 levels and/or pathologic response), a strategy defined herein as adaptive dynamic therapy.

Objective

To evaluate the association of adaptive dynamic therapy with oncologic outcomes in patients with surgically resected pancreatic cancer.

Design, Setting, and Participants

This retrospective cohort study included patients with localized pancreatic cancer who were treated with either gemcitabine/nab-paclitaxel or fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) preoperatively between 2010 and 2019 at a high-volume tertiary care academic center. Participants were identified from a prospectively maintained database and had a median follow-up of 49 months. Data were analyzed from October 17 to November 24, 2020.

Exposures

The adaptive dynamic therapy group included 219 patients who remained on or switched to an alternative regimen as dictated by CA19-9 response and for whom the adjuvant regimen was selected based on CA19-9 and/or pathologic response. The nonadaptive dynamic therapy group included 103 patients who had their chemotherapeutic regimen selected independent of CA19-9 and/or tumoral response.

Main Outcomes and Measures

Prognostic implications of dynamic perioperative therapy assessed through Kaplan-Meier analysis, Cox regression, and inverse probability weighted estimators.

Results

A total of 322 consecutive patients (mean [SD] age, 65.1 [9] years; 162 [50%] women) were identified. The adaptive dynamic therapy group, compared with the nonadaptive dynamic therapy group, had a more pronounced median (IQR) decrease in CA19-9 levels (-80% [-92% to -56%] vs -45% [-81% to -13%]; P < .001), higher incidence of complete or near-complete tumoral response (25 [12%] vs 2 [2%]; P = .007), and lower median (IQR) number of lymph node metastasis (1 [0 to 4] vs 2 [0 to 4]; P = .046). Overall survival was significantly improved in the dynamic group compared with the nondynamic group (38.7 months [95% CI, 34.0 to 46.7 months] vs 26.5 months [95% CI, 23.5 to 32.9 months]; P = .03), and on adjusted analysis, dynamic therapy was independently associated with improved survival (hazard ratio, 0.73; 95% CI, 0.53 to 0.99; P = .04). On inverse probability weighted analysis of 320 matched patients, the average treatment effect of dynamic therapy was to increase overall survival by 11.1 months (95% CI, 1.5 to 20.7 months; P = .02).

Conclusions and Relevance

In this cohort study that sought to evaluate the role of adaptive dynamic therapy in localized pancreatic cancer, selecting a chemotherapeutic regimen based on response to preoperative therapy was associated with improved survival. These findings support an individualized and in vivo assessment of response to perioperative therapy in pancreatic cancer.

Non-functional pancreatic neuroendocrine tumours: ATRX/DAXX and alternative lengthening of telomeres (ALT) are prognostically independent from ARX/PDX1 expression and tumour size

OBJECTIVE

Recent studies have found aristaless-related homeobox gene (ARX)/pancreatic and duodenal homeobox 1 (PDX1), alpha-thalassemia/mental retardation X-linked (ATRX)/death domain-associated protein (DAXX) and alternative lengthening of telomeres (ALT) to be promising prognostic biomarkers for non-functional pancreatic neuroendocrine tumours (NF-PanNETs). However, they have not been comprehensively evaluated, especially among small NF-PanNETs (≤2.0 cm). Moreover, their status in neuroendocrine tumours (NETs) from other sites remains unknown.

DESIGN

An international cohort of 1322 NETs was evaluated by immunolabelling for ARX/PDX1 and ATRX/DAXX, and telomere-specific fluorescence in situ hybridisation for ALT. This cohort included 561 primary NF-PanNETs, 107 NF-PanNET metastases and 654 primary, non-pancreatic non-functional NETs and NET metastases. The results were correlated with numerous clinicopathological features including relapse-free survival (RFS).

RESULTS

ATRX/DAXX loss and ALT were associated with several adverse prognostic findings and distant metastasis/recurrence (p<0.001). The 5-year RFS rates for patients with ATRX/DAXX-negative and ALT-positive NF-PanNETs were 40% and 42% as compared with 85% and 86% for wild-type NF-PanNETs (p<0.001 and p<0.001). Shorter 5-year RFS rates for ≤2.0 cm NF-PanNETs patients were also seen with ATRX/DAXX loss (65% vs 92%, p=0.003) and ALT (60% vs 93%, p<0.001). By multivariate analysis, ATRX/DAXX and ALT status were independent prognostic factors for RFS. Conversely, classifying NF-PanNETs by ARX/PDX1 expression did not independently correlate with RFS. Except for 4% of pulmonary carcinoids, ATRX/DAXX loss and ALT were only identified in primary (25% and 29%) and NF-PanNET metastases (62% and 71%).

CONCLUSIONS

ATRX/DAXX and ALT should be considered in the prognostic evaluation of NF-PanNETs including ≤2.0 cm tumours, and are highly specific for pancreatic origin among NET metastases of unknown primary.

Tumor Size Differences Between Preoperative Endoscopic Ultrasound and Postoperative Pathology for Neoadjuvant-Treated Pancreatic Ductal Adenocarcinoma Predict Patient Outcome

BACKGROUND & AIMS

The assessment of therapeutic response after neoadjuvant treatment and pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) has been an ongoing challenge. Several limitations have been encountered when employing current grading systems for residual tumor. Considering endoscopic ultrasound (EUS) represents a sensitive imaging technique for PDAC, differences in tumor size between preoperative EUS and postoperative pathology after neoadjuvant therapy were hypothesized to represent an improved marker of treatment response.

METHODS

For 340 treatment-naïve and 365 neoadjuvant-treated PDACs, EUS and pathologic findings were analyzed and correlated with patient overall survival (OS). A separate group of 200 neoadjuvant-treated PDACs served as a validation cohort for further analysis.

RESULTS

Among treatment-naïve PDACs, there was a moderate concordance between EUS imaging and postoperative pathology for tumor size (r = 0.726, P < .001) and AJCC 8^th edition T-stage (r = 0.586, P < .001). In the setting of neoadjuvant therapy, a decrease in T-stage correlated with improved 3-year OS rates (50% vs 31%, P < .001). Through recursive partitioning, a cutoff of ≥47% tumor size reduction was also found to be associated with improved OS (67% vs 32%, P < .001). Improved OS using a ≥47% threshold was validated using a separate cohort of neoadjuvant-treated PDACs (72% vs 36%, P < .001). By multivariate analysis, a reduction in tumor size by ≥47% was an independent prognostic factor for improved OS (P = .007).

CONCLUSIONS

The difference in tumor size between preoperative EUS imaging and postoperative pathology among neoadjuvant-treated PDAC patients is an important prognostic indicator and may guide subsequent chemotherapeutic management.

Pembrolizumab plus azacitidine in patients with chemotherapy refractory metastatic colorectal cancer: a single-arm phase 2 trial and correlative biomarker analysis

BACKGROUND

DNA mismatch repair proficient (pMMR) metastatic colorectal cancer (mCRC) is not responsive to pembrolizumab monotherapy. DNA methyltransferase inhibitors can promote antitumor immune responses. This clinical trial investigated whether concurrent treatment with azacitidine enhances the antitumor activity of pembrolizumab in mCRC.

METHODS

We conducted a phase 2 single-arm trial evaluating activity and tolerability of pembrolizumab plus azacitidine in patients with chemotherapy-refractory mCRC (NCT02260440). Patients received pembrolizumab 200 mg IV on day 1 and azacitidine 100 mg SQ on days 1-5, every 3 weeks. A low fixed dose of azacitidine was chosen in order to reduce the possibility of a direct cytotoxic effect of the drug, since the main focus of this study was to investigate its potential immunomodulatory effect. The primary endpoint of this study was overall response rate (ORR) using RECIST v1.1., and secondary endpoints were progression-free survival (PFS) and overall survival (OS). Tumor tissue was collected pre- and on-treatment for correlative studies.

RESULTS

Thirty chemotherapy-refractory patients received a median of three cycles of therapy. One patient achieved partial response (PR), and one patient had stable disease (SD) as best confirmed response. The ORR was 3%, median PFS was 1.9 months, and median OS was 6.3 months. The combination regimen was well-tolerated, and 96% of treatment-related adverse events (TRAEs) were grade 1/2. This trial was terminated prior to the accrual target of 40 patients due to lack of clinical efficacy. DNA methylation on-treatment as compared to pre-treatment decreased genome wide in 10 of 15 patients with paired biopsies and was significantly lower in gene promoter regions after treatment. These promoter demethylated genes represented a higher proportion of upregulated genes, including several immune gene sets, endogenous retroviral elements, and cancer-testis antigens. CD8+ TIL density trended higher on-treatment compared to pre-treatment. Higher CD8+ TIL density at baseline was associated with greater likelihood of benefit from treatment. On-treatment tumor demethylation correlated with the increases in tumor CD8+ TIL density.

CONCLUSIONS

The combination of pembrolizumab and azacitidine is safe and tolerable with modest clinical activity in the treatment for chemotherapy-refractory mCRC. Correlative studies suggest that tumor DNA demethylation and immunomodulation occurs. An association between tumor DNA demethylation and tumor-immune modulation suggests immune modulation and may result from treatment with azacitidine. Trial registration ClinicalTrials.gov, NCT02260440. Registered 9 October 2014, https://clinicaltrials.gov/ct2/show/NCT02260440 .

The Role of Adjuvant Chemotherapy Following Right Hemicolectomy for Non-metastatic Mucinous and Nonmucinous Appendiceal Adenocarcinoma

BACKGROUND

Appendiceal adenocarcinoma (AA) represents a heterogenous group of neoplasms with distinct histologic features. The role and efficacy of adjuvant chemotherapy (AC) in non-metastatic disease remain controversial. The aim of this study was to ascertain the role of AC in non-metastatic AA in a national cohort of patients.

METHODS

The National Cancer Database (NCDB) was queried to identify patients diagnosed with stage I-III mucinous and nonmucinous AA who underwent right hemicolectomy between 2006 and 2016. Kaplan-Meier and Cox regression analyses were used to evaluate the impact of AC on overall survival (OS) stratified by each pathologic stage.

RESULTS

A total of 1433 mucinous and 1954 nonmucinous AA were identified; 578 (40%) and 722 (40%) received AC respectively. In both AC groups, there was a higher proportion of T4 disease, lymph node metastasis, pathologic stage III, and poorly/undifferentiated grade (all P<0.05). On unadjusted analysis, there was no significant association between AC and OS for stage I-III mucinous AA. For nonmucinous AA, AC significantly improved OS only for stage II and III disease. On adjusted analysis, AC was independently associated with an improved OS for stage III nonmucinous AA (HR: 0.61, 95%CI 0.45-0.84, P=0.002), while for mucinous AA, AC was associated with worse outcomes for stage I/II disease (HR: 1.4, 95%CI 1.02-1.91, P=0.038) and had no significant association with OS for stage III disease.

CONCLUSION

This current analysis of a national cohort of patients suggests a beneficial role for AC in stage III nonmucinous AA and demonstrates no identifiable benefit for stage I-III mucinous AA.

344 Avelumab + binimetinib in metastatic pancreatic ductal adenocarcinoma (mPDAC): dose-escalation results from the phase 1b/2 JAVELIN PARP MEKi trial

Background

Preclinical studies of avelumab (anti–PD-L1) + binimetinib (MEK inhibitor [MEKi]) showed encouraging antitumor activity. We report results from the phase 1b JAVELIN PARP MEKi trial (NCT03637491) evaluating avelumab + binimetinib in patients with mPDAC.

Methods

Eligible patients had mPDAC and disease progression during or following 1–2 prior lines for advanced or metastatic disease. Patients received avelumab 800 mg intravenously every 2 weeks and binimetinib 30 or 45 mg orally twice daily. The primary endpoint for phase 1b was dose-limiting toxicity (DLT). Secondary endpoints included safety, confirmed objective response per investigator (RECIST 1.1), pharmacokinetics, immunogenicity, and biomarker analyses. PD-L1 expression (SP263 assay) and CD8+ tumor-infiltrating lymphocytes (TILs) in baseline tumor samples were assessed using immunohistochemistry. Molecular alterations were assessed via plasma ctDNA analyses. Blood samples were collected to assess trough concentrations for avelumab, binimetinib, and AR00426032 (binimetinib metabolite) and end-of-infusion concentration for avelumab.

Results

22 patients received avelumab + binimetinib 30 mg (n=10) or 45 mg (n=12); all discontinued treatment. Among 21 DLT-evaluable patients, DLTs occurred in 3/10 (30.0%) in the 30-mg group (mucosal inflammation, dermatitis acneiform, blood creatine phosphokinase increased [n=1 each]) and 5/11 (45.5%) in the 45-mg group (detachment of retinal pigment epithelium, abdominal pain, diarrhea, nausea, vomiting, rash pustular, hypertension, blood creatine phosphokinase increased [n=1 each]). Any-grade treatment-related adverse events (TRAEs) occurred in all 22 patients; grade =3 TRAEs occurred in 8 (80.0%) and 4 (33.3%) in the 30- and 45-mg groups, respectively, most commonly blood creatine phosphokinase increased (n=3 [30.0%], n=2 [16.7%], respectively). No treatment-related deaths occurred. Objective response rates (95% CI) in the 30- and 45-mg groups were 0% (0.0–30.8) and 8.3% (0.2–38.5; 1 partial response), respectively; 1 (10.0%) and 6 (50.0%) had a best overall response of stable disease. Tumor shrinkage was associated with higher baseline PD-L1 expression, higher number of CD8+ TILs, and MEK1/2, PIK3CA, and RNF43 alterations, whereas ERBB4 alterations correlated inversely with tumor size change. Available data indicate that avelumab, binimetinib, and AR00426032 exposures were within range of previous monotherapy studies.

Conclusions

This study was terminated before a recommended phase 2 dose was established. In patients with mPDAC who received avelumab + binimetinib, DLTs occurred in both dose groups, although TRAEs were generally consistent with single agent safety profiles. The 45-mg binimetinib dose had a higher number of patients with stable disease and one confirmed partial response. Biomarker findings provide insights into potential mechanisms of treatment resistance and response.

Trial Registration

NCT03637491

Ethics Approval

The trial was approved by each site’s independent ethics committee.

Encouraging long-term survival following autophagy inhibition using neoadjuvant hydroxychloroquine and gemcitabine for high-risk patients with resectable pancreatic carcinoma

INTRODUCTION

Preoperative autophagy inhibition with hydroxychloroquine (HCQ) in combination with gemcitabine in pancreatic adenocarcinoma (PDAC) has been shown to be safe and effective in inducing a serum biomarker response and increase resection rates in a previous phase I/II clinical trial. We aimed to analyze the long-term outcomes of preoperative HCQ with gemcitabine for this cohort.

METHODS

A review of patients enrolled between July 2010 and February 2013 in the completed phase I/II single arm (two doses of fixed-dose gemcitabine (1500 mg/m2 ) in combination with oral hydroxychloroquine administered for 31 consecutive days until the day of surgery for high-risk pancreatic cancer) was undertaken. Progression-free survival (PFS) and overall survival analysis (OS) using Kaplan-Meier estimates were performed.

RESULTS

Of 35 patients initially enrolled, 29 patients underwent surgical resection (median age at diagnosis: 62 years, 45% females). Median duration of follow-up was 7.5 years. There was a median 15% decrease in the serum CA19-9 levels following completion of neoadjuvant therapy and 83% of the cohort underwent a pancreaticoduodenectomy, 7 (24%) patients had a concomitant venous resection. On histopathology, 14 (48%) patients had at least a partial treatment response. The median PFS and OS were 11 months (95% Confidence interval [CI]: 7-28) and 31 months (95% CI: 13-47), respectively, while 9 (31%) patients survived beyond 5 years from diagnosis; a rate that compares very favorably with contemporaneous series.

CONCLUSION

Compared to historical data, neoadjuvant autophagy inhibition with HCQ plus gemcitabine is associated with encouraging long-term survival for patients with PDAC.

Clinical Outcomes Among Patients With Metastatic Pancreatic Ductal Adenocarcinoma Treated With Liposomal Irinotecan

Background

The NAPOLI-1 trial demonstrated that liposomal irinotecan in combination with fluorouracil (5-FU) and leucovorin (LV) prolonged survival with a manageable safety profile in patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) previously treated with gemcitabine-based therapy. Real-world data on clinical outcomes associated with liposomal irinotecan in NAPOLI-1-based regimens is needed to further substantiate this.

Methods

This real-world, retrospective chart review study included patients with mPDAC who received NAPOLI-1-based regimens from six academic centers in the United States. Liposomal irinotecan initiation defined the index date. Overall survival (OS) and progression-free survival (PFS) were assessed with Kaplan-Meier methodology.

Results

There were 374 patients evaluated; median age was 68 years, and 51% were female. Among 326 patients with baseline ECOG information, approximately 74% had ECOG score <2. Liposomal irinotecan was administered as a doublet with 5-FU in a NAPOLI-1-based regimen in the first line (1L; 16%), 2L (42%), and 3L+ (42%) of the metastatic setting. For patients treated in 1L, 2L, and 3L+, median [95% confidence interval (CI)] OS was 8.0 [5.1, 11.2], 7.3 [5.3, 8.8], and 4.6 [4.0, 5.7] months, and median [95% CI] PFS was 4.2 [2.2, 6.6], 3.0 [2.6, 3.7], and 2.0 [1.7, 2.2] months, respectively.

Conclusions

Patients in a real-world setting treated with NAPOLI-1-based liposomal irinotecan doublet regimens at academic centers were older with poorer performance status compared to trial patients yet had similar outcomes and efficacy. Furthermore, liposomal irinotecan was frequently used in the 3L+ setting where no treatment has been approved and provided clinical benefit.

Optimal management of patients with operable pancreatic head cancer: A Markov decision analysis

INTRODUCTION

Neoadjuvant therapy (NAT) is an emerging strategy for operable pancreatic ductal adenocarcinoma (PDAC). While NAT increases multimodal therapy completion, it risks functional decline and treatment dropout. We used decision analysis to determine optimal management of localized PDAC and consider risks faced by elderly patients.

METHODS

A Markov cohort decision analysis model evaluated treatment options for a 60-year-old patient with resectable PDAC: (1) upfront pancreaticoduodenectomy or (2) NAT. One-way and probabilistic sensitivity analyses were performed. A subanalysis considered the scenario of a 75-year-old patient.

RESULTS

For the base case, NAT offered an incremental survival gain of 4.6 months compared with SF (overall survival: 26.3 vs. 21.7 months). In one-way sensitivity analyses, findings were sensitive to recurrence-free survival for NAT patients undergoing adjuvant, probability of completing NAT, and probability of being resectable at exploration after NAT. On probabilistic analysis, NAT was favored in a majority of trials (97%) with a median survival benefit of 5.1 months. In altering the base case for the 75-year-old scenario, NAT had a survival benefit of 3.8 months.

CONCLUSIONS

This analysis demonstrates a significant benefit to NAT in patients with localized PDAC. This benefit persists even in the elderly cohort.

Impact of Neoadjuvant Therapy on Survival Following Margin-Positive Resection for Pancreatic Cancer

INTRODUCTION

A positive microscopic margin (R1) following resection of pancreatic ductal adenocarcinoma (PDAC) can occur in up to 80% of patients and is associated with reduced survival and increased recurrence. Our aim was to characterize the impact of neoadjuvant therapy (NAT) on survival and recurrence in patients with PDAC following an R1 resection.

METHODS

A retrospective analysis of patients with PDAC who underwent pancreatectomy from 2008 to 2017 was performed. Patients were staged according to the American Joint Committee on Cancer 8th edition and stratified based on resection margin (R0 vs. R1) and treatment sequence (NAT vs. surgery first [SF]). Conditional survival analysis was performed using Cox regression and inverse probability weighted estimates.

RESULTS

Among 580 patients, 59% received NAT and 41% underwent SF. On final pathology, the NAT cohort had smaller tumors and less lymph node (LN) positivity (p < 0.05). NAT was not associated with an R1 resection (50%, p = 0.653). Compared with the R1 cohort, the R0 cohort had a higher median overall survival (OS; 39.6 vs. 22.8 months; hazard ratio [HR] 1.6, p < 0.001) and disease-free survival (DFS; 19 vs. 13 months; HR 1.35, p = 0.004). After risk adjustment, NAT was not associated with OS, regardless of margin status (R0, 95% confidence interval [CI] (-)7.31-27.07, p = 0.26; or R1, 95% CI (-)36.99-15.25, p = 0.42). However, NAT was associated with improved DFS in the R1 cohort (95% CI 1.79-11.91, p = 0.008) but not in the R0 cohort (95% CI (-)11.22-10.54, p = 0.95).

CONCLUSION

An R0 resection remains an important determinant of overall and disease-free survival, even when NAT is administered. For patients with an R1 resection, receipt of NAT may prolong DFS.

Intratumoral T cell clonality and survival in a randomized phase II study of preoperative autophagy inhibition in combination with gemcitabine and nab-paclitaxel treatment in patients with resectable pancreatic cancer

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Background: Autophagy is a cell survival mechanism that is upregulated in pancreatic ductal adenocarcinoma (PDAC). PDAC autophagy results in an altered metabolic phenotype that promotes tumor progression, chemotherapeutic resistance, and immune evasion. Methods: We previously completed a randomized phase II clinical trial of preoperative gemcitabine-nab-paclitaxel with (PGH n = 34) and without (PG, n = 30) autophagy inhibition in patients with resectable and borderline resectable PDAC, which demonstrated increased Evans Grade histopathologic and serum CA 19-9 response with autophagy inhibition (IRB 13-074, NCT01128296 ). Utilizing the resected FFPE tumor specimens from evaluable patients, we completed paired multiplex immunohistochemistry (CD4, CD8, FOXP3, CD20, CD68, Pan-CK) and T & B cell receptor RNA sequencing to assess the intratumoral adaptive immune response and correlates of outcome. Results: Autophagy inhibition increased the number of infiltrating CD8 T cells (1133±490 vs 712±460 average cells per high power field, p = 0.01), CD8:CD20 ratio (2.22±3.1 vs 0.96±1.1, p = 0.02) and reduced the CD4:CD8 ratio (2.04±0.87 vs 3.01±2.09, p = 0.03). No effect was observed on the number of immature or mature germinal center-like tertiary lymphoid structures (TLS), though the number of TLS correlated with increased infiltration of CD4 T cells (r = 0.40, p < 0.001), T-regulatory cells (r = 0.26, p = 0.03) and CD20 B cells (r = 0.65, p < 0.001). Although the total number of productive T and B cell receptors increased with autophagy inhibition (167217±105961 vs 97339±5,1628, p = 0.02), no apparent effects were observed on Vαβ TCR or BCR IgH, Igκ, Igλ clonality. Independent of treatment, intratumoral CD8 counts were associated with an improved CA 19-9 response (r = 0.32, p = 0.04) and in a subset of short term ( < 2 years, n = 17) and long term ( > 4 years, n = 10) survivors (LTS), a lowered CD4:CD8 ratio was identified in LTS (1.83±0.63 vs 2.8±0.90, p = 0.01). Dominance of B cell receptors was a prominent feature of the immune repertoire in all patients (average expression: Vα 0.6%, Vβ 0.8%, IgH 18.9%, Igκ 32.3%, Igλ 47.2%) with an IgA skewed immunoglobulin class switching (mean 63% of all BCRs). Increased αβ T cell receptor clonality above the median level was associated with a CA 19-9 response (r = 0.37, p = 0.06) and greater overall survival (median OS 38.3 vs 19.3 months, p = 0.02), indicative of possible tumor specific clonal expansion. Conclusions: Preoperative autophagy inhibition increased the number of tumor infiltrating CD8 T cells in patients with localized pancreatic cancer. Intratumoral αβ T cell receptor clonality was associated with CA 19-9 response and improved overall survival. Combination treatment regimens increasing PDAC specific CD8 responses are warranted. Clinical trial information: NCT01978184.

Impact of G-CSF during neoadjuvant therapy on outcomes of operable pancreatic cancer

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Background: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease characterized by chronic inflammation and a tolerogenic immune response. Neutropenia is a common side effect of cytotoxic chemotherapy, managed with administration of recombinant granulocyte-colony stimulating factor (G-CSF, Filgrastim). The interleukin 17 – G-CSF – neutrophil extracellular trap (NET) axis promotes oncogenesis and progression of PDAC, inhibiting adaptive immunity. We evaluated the impact of G-CSF administration during neoadjuvant therapy (NAT) on oncologic outcomes in patients with operable pancreatic cancer. Methods: A retrospective review of all patients with localized PDAC treated with NAT prior to pancreatic resection between 2014 – 2020 was completed at a single institution. G-CSF administration, type, and dose were collected from inpatient and outpatient medical records. Results: Of 351 patients treated, 138 (39%) received G-CSF during NAT with a median follow-up of 45.8 months. Patients who received G-CSF were younger (64.0 vs 66.7, p = 0.008), had lower BMI (26.5 vs 27.9, p = 0.021), and were more likely to receive 5-FU based chemotherapy (42% vs 28.2%, p < 0.0001), NAT dose reduction (40.6% vs 25.4%, p = 0.003), or experience febrile neutropenia (8.7% vs 3.3%, p = 0.029). No differences were observed in baseline or pathologic tumor staging. In patients who received G-CSF, 130 (94%) received Pegfilgrastim with a median cumulative dose of 12 mg (IQR 6-12). Patients who received G-CSF were more likely to have an elevated post-NAT neutrophil to lymphocyte ratio (45% vs 29.6%, p = 0.004) and systemic immune-inflammation index (39.5% vs 29.6%, p = 0.061). Receiving G-CSF was an independent predictor of perineural invasion (HR 2.4, 95 CI [1.08, 5.5], p = 0.031) and margin positive resection (HR 1.69, 95 CI [1.01, 2.83], p = 0.043). Patients who received G-CSF had decreased overall survival compared to patients who did not receive G-CSF (median OS: 29.2 vs 38.7 months, p = 0.0001). Receiving G-CSF during NAT was an independent negative predictor of progression free (HR 1.38, 95 CI [1.04, 1.83], p = 0.022) and overall survival (HR 2.02, 95 CI [1.45, 2.79], p < 0.0001). In a subset of patients with available pre- and post-NAT serum specimens (n = 28), G-CSF administration resulted in an increased number of citrullinated histone H3 complexes following NAT (+1378±1502 vs -300.7±1147 pg/ml, p = 0.007), indicative of enhanced peripheral NET formation. Conclusions: In patients with localized PDAC receiving NAT prior to surgical extirpation, G-CSF administration is associated with worse oncologic outcomes and should be administered with caution. Prospective randomized as well as confirmatory clinical studies are in order.

A phase II/III study of perioperative nivolumab and ipilimumab in patients (pts) with locoregional esophageal (E) and gastroesophageal junction (GEJ) adenocarcinoma: Results of a safety run-in—A trial of the ECOG-ACRIN Cancer Research Group (EA2174)

4064

Background: E/GEJ adenocarcinoma has a high mortality rate despite curative intent therapy. The use of immune checkpoint inhibition is beneficial for treatment of this cancer in the metastatic and adjuvant settings but the role of these agents in the perioperative setting remains unclear. Here we report the results of an initial safety run-in of nivolumab when given in combination with neoadjuvant chemoradiation. Methods: Pts with a localized T1N1-3M0 or T2-3N0-2M0 E/GEJ adenocarcinoma with an ECOG PS of 0-1 and whom were deemed surgical candidates for an esophagectomy by a qualified surgeon were eligible. In step 1, pts were randomized to neoadjuvant therapy with carboplatin AUC 2 and paclitaxel 50 mg/m2 intravenously (IV) weekly x 5 along with 41.4-50.4 Gy radiation without (Arm A) or with (Arm B) nivolumab 240 mg IV during weeks 1 and 3 of treatment, followed by esophagectomy. Pts underwent a second randomization (step 2) to adjuvant nivolumab 240 mg IV every 2 weeks x 12 cycles with or without ipilimumab 1 mg/kg IV every 6 weeks during cycles 1, 4, 7 and 10. For the safety run-in, 30 pts were planned for accrual to allow for 12 evaluable pts per arm. Pts were followed for safety during neoadjuvant therapy through surgery and toxicities monitored per CTCAEv5. Pre-specified early stopping rules were defined to allow halting of the trial if deemed unsafe. Planned study accrual is 278 pts. Neoadjuvant primary endpoint is pathologic complete response rate, adjuvant primary endpoint is disease-free survival. Results: A total of 31 pts were enrolled to the safety run-in element of the study (Arm A, n = 16; Arm B n = 15). Male, 94%; White, 100%; median age, 62; esophageal adenocarcinoma, 52%; GEJ, 48%. Grade (G) 3 events occurring in more than one pt on Arm A—decreased lymphocytes (n = 5). G4 events occurring on Arm A—decreased lymphocytes (n = 1). G3 events occurring in more than one pt on Arm B—decreased lymphocytes (n = 2); anemia (n = 2); leukopenia (n = 4); hypotension (n = 2). G4 events occurring on Arm B—decreased lymphocytes (n = 3); cardiac tamponade and pericardial effusion (n = 1). Cardiac events were thought to be secondary to tumor location, not neoadjuvant treatment. On Arm B, notable G3 events seen in one pt each included colonic obstruction, wound infection and esophageal anastomotic leak. Of pts who have reached the time for surgery, 12/14 pts on Arm A and 13/13 pts on Arm B have proceeded to surgery. Of pts who have completed step 1, 7/14 pts on Arm A and 8/11 pts on Arm B have registered to step 2. Conclusions: The addition of nivolumab to carboplatin, paclitaxel and radiation in the neoadjuvant setting appears to be safe with no disproportionate level of toxicity observed between the two treatment arms. Accrual to the remainder of the trial continues with 43/278 patients accrued. Clinical trial information: NCT03604991.

SMAD4 loss is associated with response to neoadjuvant chemotherapy plus hydroxychloroquine in patients with pancreatic adenocarcinoma

SMAD4, a tumor suppressor gene, is lost in up to 60%–90% of pancreatic adenocarcinomas (PDAs). Loss of SMAD4 allows tumor progression by upregulating autophagy, a cell survival mechanism that counteracts apoptosis and allows intracellular recycling of macromolecules. Hydroxychloroquine (HCQ) is an autophagy inhibitor. We studied whether HCQ treatment in SMAD4 deficient PDA may prevent therapeutic resistance induced by autophagy upregulation. We retrospectively analyzed the SMAD4 status of patients with PDA enrolled in two prospective clinical trials evaluating pre‐operative HCQ. The first dose escalation trial demonstrated the safety of preoperative gemcitabine with HCQ (NCT01128296). More recently, a randomized trial of gemcitabine/nab‐paclitaxel +/− HCQ evaluated Evans Grade histopathologic response (NCT01978184). The effect of SMAD4 loss on response to HCQ and chemotherapy was studied for association with clinical outcome. Fisher’s exact test and log‐rank test were used to assess response and survival. Fifty‐two patients receiving HCQ with neoadjuvant chemotherapy were studied. Twenty‐five patients had SMAD4 loss (48%). 76% of HCQ‐treated patients with SMAD4 loss obtained a histopathologic response greater than or equal to 2A, compared with only 37% with SMAD4 intact (p = 0.006). Although loss of SMAD4 has been associated with worse outcomes, in the current study, loss of SMAD4 was not associated with a detriment in median overall survival in HCQ‐treated patients (34.43 months in SMAD4 loss vs. 27.27 months in SMAD4 intact, p = 0.18). The addition of HCQ to neoadjuvant chemotherapy in patients with PDA may improve treatment response in those with SMAD4 loss. Further study of the relationship among SMAD4, autophagy, and treatment outcomes in PDA is warranted.

Predictors of early recurrence following neoadjuvant chemotherapy and surgical resection for localized pancreatic adenocarcinoma

BACKGROUND AND OBJECTIVES

Neoadjuvant chemotherapy (NAT) for pancreatic adenocarcinoma (PDAC) is increasingly being utilized. However, a significant number of patients will experience early recurrence, possibly negating the benefit of surgery. We aimed to identify factors implicated in early disease recurrence.

METHODS

A retrospective review of pancreaticoduodenectomies performed between 2005 and 2017 at our institution for PDAC following NAT was performed. A 6-month cut-off was used to stratify patients into early/late recurrence groups. Multivariate analysis was performed to identify predictors of recurrence.

RESULTS

Of 273 patients, 64 (23%) developed early recurrence or died within 90 days of surgery. The median time to recurrence was 4 months (95% confidence interval [CI]: 2.2-4.3) in the early group versus 16 months (95% CI: 13.7-19.9) in the late group. The former had higher baseline and post-NAT Ca19-9 levels than the latter (472 vs. 153 IU/ml, p = 0.001 and 71 vs. 39 IU/ml, p = 0.005, respectively). A higher positive lymph node ratio significantly increased the risk of early recurrence (hazard ratio [HR]: 15.9, p < 0.001) while adjuvant chemotherapy was protective (HR: 0.4, p < 0.001).

CONCLUSION

Our findings acknowledge the limitations of clinically measured factors used to ascertain response to NAT and underline the need for individualized molecular markers that take into consideration the specific tumor biology.

Optimal Management of Resectable Pancreatic Head Cancer in the Elderly Patient: Does Neoadjuvant Therapy Offer a Survival Benefit?

INTRODUCTION

Neoadjuvant therapy (NAT) is a growing strategy for patients with resectable pancreatic ductal adenocarcinoma (PDAC). Elderly patients are at increased risk of treatment withdrawal due to functional decline, and the benefit of NAT in this cohort remains to be studied.

OBJECTIVE

The objective of this study was to compare outcomes of elderly patients with resectable head PDAC who underwent NAT or a surgery-first (SF) approach.

METHODS

All patients 75 years of age and older with radiographically resectable (National Comprehensive Cancer Network criteria) PDAC who underwent pancreaticoduodenectomy at a single institution from 2008 to 2017 were analyzed. Baseline characteristics and perioperative outcomes were compared between the SF and NAT cohorts. Recurrence-free survival and overall survival (OS) were analyzed by treatment strategy.

RESULTS

Overall, 158 patients were identified: SF cohort = 90 (57%) and NAT cohort = 68 (43%). Patients in the SF cohort were older (80 vs. 78 years; p = 0.01) but there were no differences in preoperative comorbidities or frailty indices. SF patients had a trend toward higher rates of major complications (38% vs. 24%; p = 0.06) with higher Comprehensive Complication Index totals (20.9 vs. 20; p = 0.03). There were similar rates of adjuvant therapy. NAT was associated with significantly longer OS (24.6 vs. 17.6 months; p = 0.01) in both the intent-to-treat and resected cohorts. On multivariable analysis (MVA), NAT remained an independent predictor of OS (hazard ratio 0.60; p = 0.02).

CONCLUSION

NAT is safe and effective for elderly patients with PDAC. This study suggests NAT is associated with fewer complications after surgery, equal rates of adjuvant therapy receipt, and increased OS over a surgery-first approach.

Current Management of Appendiceal Neoplasms

Appendiceal neoplasms include a heterogeneous group of epithelial and nonepithelial tumors that exhibit varying malignant potential. This review article summarizes current diagnostic criteria, classification systems, and optimal therapeutic strategies for the five main histopathologic subtypes of appendiceal neoplasms. In particular, the management of epithelial appendiceal neoplasms has evolved. Although their treatment has historically been extrapolated from colon cancer, improved understanding of their unique histopathologic and molecular characteristics and a growing body of published clinical data support a more nuanced approach to their management.

A Pancreatic Cancer Multidisciplinary Clinic Eliminates Socioeconomic Disparities in Treatment and Improves Survival

AIMS

National studies have demonstrated disparities in the treatment and survival of pancreatic cancer patients based on socioeconomic status (SES). This study aimed to identify specific differences in perioperative management and outcomes based on patient SES and to study the role of a multidisciplinary clinic (MDC) in mitigating any variations.

METHODS

The study analyzed patients undergoing pancreaticoduodenectomy for pancreatic ductal adenocarcinoma in a large hospital system. The patients were categorized into groups of high and low SES and whether they were managed by the authors' pancreatic cancer MDC or not. The study compared differences in disease characteristics, receipt of multimodality therapy, perioperative outcomes, and recurrence-free and overall survival.

RESULTS

Of the 162 low-SES patients and 119 high-SES patients, 54% were managed in the MDC. Outside the MDC, low-SES patients were less likely to receive neoadjuvant chemotherapy and had less minimally invasive surgery, a longer OR time, less enhanced recovery participation, and more major complications (p < 0.05). No SES disparities were observed among the MDC patients. Despite similar tumor characteristics, the low-SES patients had inferior median overall survival (21 vs 32 months; p = 0.005), but the MDC appeared to eliminate this disparity. Low SES correlated with inferior survival for the non-MDC patients (17 vs 32 months; p < 0.001), but not for the MDC patients (24 vs 25 months; p = 0.33). These findings persisted in the multivariable analysis.

CONCLUSION

A pancreatic cancer MDC standardizes treatment decisions, eliminates disparities in surgical outcomes, and improves survival for low-SES patients.

Neoadjuvant Chemotherapy for Pancreatic Adenocarcinoma Lessens the Deleterious Effect of Omission of Adjuvant Chemotherapy

BACKGROUND

Despite controversy regarding the role of neoadjuvant chemotherapy (NAC) in pancreatic adenocarcinoma, nearly half of resected patients do not receive chemotherapy postoperatively. This study aimed to examine whether use of NAC compensates for omission of adjuvant chemotherapy (AC) for resected pancreatic adenocarcinoma.

METHODS

Adults with resected stages 1 to 3 pancreatic adenocarcinoma were enrolled from the National Cancer Database NCDB (2006-2016). Overall survival (OS) analyses were used to examine the impact of NAC on those who did not receive AC.

RESULTS

The study analyzed a national cohort of 56,286 patients: 30% without chemotherapy, 11% with NAC, 54% with AC, and 5% with NAC plus AC. Use of NAC increased by more than 400% from 2006 to 2016, whereas the rates for omission of chemotherapy remained unchanged. The OS rates were similar between the patients who received NAC and those who received AC (hazard ratio, 0.97; p = 0.21). Among the patients who did not receive AC, NAC was associated with improved OS (26.7 vs. 18.4 months; p < 0.0001). The patients who did not receive AC but underwent NAC had a median OS comparable with the OS of those who received AC alone (26.9 vs. 24.7 months). In the adjusted analysis, the use of NAC for those without AC was significantly associated with improved OS (estimate, - 0.24; p < 0.0001).

CONCLUSIONS

Although data are limited regarding the survival benefit derived from neoadjuvant versus adjuvant chemotherapy in pancreatic adenocarcinoma, nearly half of patients do not receive adjuvant chemotherapy. This study demonstrates that the use of NAC lessens the survival disadvantage caused by omission of AC. Despite controversy, NAC may be considered for pancreatic adenocarcinoma patients given the high likelihood that adjuvant chemotherapy will be omitted.

Intratumoral budding and automated CD8-positive T-cell density in pretreatment biopsies can predict response to neoadjuvant therapy in rectal adenocarcinoma

Tumor budding and CD8-positive (+) T-cells are recognized as prognostic factors in colorectal adenocarcinoma. We assessed CD8+ T-cell density and intratumoral budding in pretreatment rectal cancer biopsies to determine if they are predictive biomarkers for response to neoadjuvant therapy and survival. Pretreatment biopsies of locally advanced rectal adenocarcinoma from 117 patients were evaluated for CD8+ T-cell density using automated quantitative digital image analysis and for intratumoral budding and correlated with clinicopathological variables on postneoadjuvant surgical resection specimens, response to neoadjuvant therapy, and survival. Patients with high CD8+ T-cell density (≥157 per mm²) on biopsy were significantly more likely to exhibit complete/near complete response to neoadjuvant therapy (66% vs. 33%, p = 0.001) and low tumor stage (0 or I) on resection (62% vs. 30%, p = 0.001) compared with patients with low CD8+ T-cell density. High CD8+ T-cell density was an independent predictor of response to neoadjuvant therapy with a 2.63 higher likelihood of complete response (95% CI 1.04-6.65, p = 0.04) and a 3.66 higher likelihood of complete/near complete response (95% CI 1.60-8.38, p = 0.002). The presence of intratumoral budding on biopsy was significantly associated with a reduced likelihood of achieving complete/near complete response to neoadjuvant therapy (odds ratio 0.36, 95% CI 0.13-0.97, p = 0.048). Patients with intratumoral budding on biopsy had a significantly reduced disease-free survival compared with patients without intratumoral budding (5-year survival 39% vs 87%, p < 0.001). In the multivariable model, the presence of intratumoral budding on biopsy was associated with a 3.35-fold increased risk of tumor recurrence (95% CI 1.25-8.99, p = 0.02). In conclusion, CD8+ T-cell density and intratumoral budding in pretreatment biopsies of rectal adenocarcinoma are independent predictive biomarkers of response to neoadjuvant therapy and intratumoral budding associates with patient survival. These biomarkers may be helpful in selecting patients who will respond to neoadjuvant therapy and identifying patients at risk for recurrence.

Outcomes of Neoadjuvant Chemotherapy Versus Chemoradiation in Localized Pancreatic Cancer: A Case-Control Matched Analysis

BACKGROUND

Neoadjuvant therapy is increasingly used for patients with pancreatic ductal adenocarcinoma (PDAC). It is unknown whether neoadjuvant chemoradiotherapy is more effective than chemotherapy (NCRT vs. NAC). We aim to compare pathological and survival outcomes of NCRT and NAC in patients with PDAC.

PATIENTS AND METHODS

Single-center analysis of PDAC patients treated with NCRT or NAC followed by resection between December 2008 and December 2018 was performed. Average treatment effect (ATE) was estimated after case-control matching using Mahalanobis distance nearest-neighbor matching. Inverse probability weighted estimates (IPWE)-based ATE was estimated for disease-free survival (DFS) and overall survival (OS).

RESULTS

Among the 418 patients (mean age 66.8 years, 51% female) included in the study, 327 received NAC and 91 received NCRT. NCRT patients had higher rates of locally advanced disease, number of neoadjuvant chemotherapy cycles, more chemotherapy regimen crossover (gemcitabine and 5-FU based), and were more likely to undergo open surgical procedures and/or vascular resection (all p < 0.05). After matched analysis, NCRT was associated with a significant reduction in lymph node positive disease [ATE = (-)0.24, p = 0.007] and lymphovascular invasion [ATE = (-)0.20, p = 0.02]. While NCRT was associated with significantly improved DFS by 9.5 months (p = 0.006), it did not affect OS by IPWE-based ATE after adjusting for adjuvant therapy (ATE = 5.5 months; p = 0.32).

CONCLUSION

Compared with NAC alone, NCRT is associated with improved pathologic surrogates and disease-free survival, but not overall survival in patients with PDAC.

Neoadjuvant therapy versus upfront surgery for early-stage left-sided pancreatic adenocarcinoma: A propensity-matched analysis from a national cohort of distal pancreatectomies

BACKGROUND

There are limited data on the efficacy of neoadjuvant therapy (NAT) for early-stage distal pancreas adenocarcinoma (PDAC). Previous studies focused on adenocarcinoma of the head of the pancreas or dealt with borderline and locally advanced tumors of the body and tail.

METHODS

This is a retrospective study of the National Cancer Database between 2006 and 2015. A propensity-matched analysis was performed to compare overall survival estimates between NAT and upfront resection (UR) groups.

RESULTS

A total of 5003 distal pancreatectomies for PDAC were identified, of whom 408 (9%) received NAT. After 1:1 matching, 353 NAT patients were compared with 353 UR patients. NAT was associated with lower 90-day mortality. There were no differences in the number of lymph nodes retrieved, or length of stay. With matching, the NAT group had higher median overall survival compared with UR (33.0 vs. 27.0 months; p = 0.009) and adjusted overall survival (hazard ratio = 0.63, 95% confidence interval = 0.51-0.77; p < 0.001).

CONCLUSION

The receipt of NAT followed by distal pancreatectomy for early-stage distal PDAC is associated with improved overall survival compared with UR. This study supports the use of NAT in the multimodal therapy paradigm of early-stage adenocarcinoma of the body and tail of the pancreas.

CA19-9 Change During Neoadjuvant Therapy May Guide the Need for Additional Adjuvant Therapy Following Resected Pancreatic Cancer

BACKGROUND

Neoadjuvant therapy (NAT) is increasingly utilized for pancreatic cancer, however the added benefit of adjuvant therapy (AT) in this setting is unknown. We hypothesized that the magnitude of CA19-9 response to NAT can guide the need for further AT in resected pancreatic cancer.

METHODS

CA19-9 secretors who received NAT for pancreatic cancer during 2008-2016 at a single institution were analyzed and CA19-9 response (difference between pre- and post-NAT values) was measured. Kaplan-Meier estimators and Cox proportional hazard ratio models were used to determine the optimal CA19-9 response at which AT ceases to confer any additional survival benefit after NAT.

RESULTS

A total of 241 patients (mean age 65.4 years, 50% female) with complete CA19-9 data who underwent NAT followed by resection were analyzed. In a cohort of patients (n = 78) in whom CA19-9 normalized with a decrease > 50% after NAT (optimal responders), AT was not associated with additional survival benefit (40.6 vs. 39.0 months, p = 0.815). Conversely, in the cohort of patients (n = 163) in whom NAT was not associated with normalization and a decrease of ≤ 50% in CA19-9 (suboptimal responders), receipt of AT was associated with a survival benefit (34.5 vs. 19.1 months, p < 0.001) following NAT. A Cox proportional hazards model confirmed CA19-9 normalization and decrease > 50% during NAT to predict no additional survival benefit from AT.

CONCLUSIONS

The magnitude of CA19-9 response to NAT may predict the need for further AT in resected pancreatic cancer. Prospective studies are needed to elucidate the optimal interplay of NAT and AT in pancreatic cancer.

KRAS amplification in metastatic colon cancer is associated with a history of inflammatory bowel disease and may confer resistance to anti-EGFR therapy

Mutations in RAS occur in 30-50% of metastatic colorectal carcinomas (mCRCs) and correlate with resistance to anti-EGFR therapy. Consequently, mCRC biomarker guidelines state RAS mutational testing should be performed when considering EGFR inhibitor treatment. However, a small subset of mCRCs are reported to harbor RAS amplification. In order to elucidate the clinicopathologic features and anti-EGFR treatment response associated with RAS amplification, we retrospectively reviewed a large cohort of mCRC patients that underwent targeted next-generation sequencing and copy number analysis for KRAS, NRAS, HRAS, BRAF, and PIK3CA. Molecular testing was performed on 1286 consecutive mCRC from 1271 patients as part of routine clinical care, and results were correlated with clinicopathologic findings, mismatch repair (MMR) status and follow-up. RAS amplification was detected in 22 (2%) mCRCs and included: KRAS, NRAS, and HRAS for 15, 5, and 2 cases, respectively (6-21 gene copies). Patients with a KRAS-amplified mCRC were more likely to report a history of inflammatory bowel disease (p < 0.001). In contrast, mutations in KRAS were associated with older patient age, right-sided colonic origin, low-grade differentiation, mucinous histology, and MMR proficiency (p ≤ 0.017). Four patients with a KRAS-amplified mCRC and no concomitant RAS/BRAF/PIK3CA mutations received EGFR inhibitor-based therapy, and none demonstrated a clinicoradiographic response. The therapeutic impact of RAS amplification was further evaluated using a separate, multi-institutional cohort of 23 patients. Eight of 23 patients with KRAS-amplified mCRC received anti-EGFR therapy and all 8 patients exhibited disease progression on treatment. Although the number of KRAS-amplified mCRCs is limited, our data suggest the clinicopathologic features associated with mCRC harboring a KRAS amplification are distinct from those associated with a KRAS mutation. However, both alterations seem to confer EGFR inhibitor resistance and, therefore, RAS testing to include copy number analyses may be of consideration in the treatment of mCRC.

Patterns of Failure After Adjuvant Stereotactic Body Radiation Therapy for Pancreatic Cancer With Close or Positive Margins

Purpose

There is no consensus on treatment volumes for adjuvant stereotactic body radiation therapy (SBRT) for pancreatic cancer. Herein, we report patterns of failure after pancreatic SBRT for close/positive margins, which may inform target volume design.

Methods and Materials

An institutional review board-approved retrospective review of patients with pancreatic adenocarcinoma treated with adjuvant SBRT for close/positive margins from 2009 to 2018 was conducted. Patterns of failure were defined as local (LF) within the tumor bed, regional (RF) within lymph nodes or anastomoses, or distant (DF). The cumulative incidence of locoregional failure was calculated using the cumulative incidence function accounting for the competing risk of death. LFs were mapped to the planning target volume (PTV) and classified as in-field (completely within the PTV), marginal (partially within the PTV), or out-of-field (completely outside the PTV). The location of LFs was compared with the Radiation Therapy Oncology Group 0848 contouring atlas to determine whether standard postoperative radiation therapy volumes would have included the LF.

Results

Seventy-six patients were treated with adjuvant SBRT for close (51.3%) or positive (48.7%) margins. Most (81.6%) received 36 Gy in 3 fractions, with a median PTV volume of 17.8 cc (interquartile range, 12.1-25.6). With a median follow-up of 17.0 months (interquartile range, 7.3-28.4), crude rates of first isolated LF, isolated RF, and DF +/- LF or RF were 9.2%, 6.6%, and 56.6%, respectively. Two-year cumulative incidences of LF, RF, locoregional failure, and DF were 34.9%, 30.8%, 49.2%, and 60.4%, respectively. Of 28 reviewable LFs, 21.4% were in-field while the remainder were completely outside (60.7%) or partially outside (17.9%) the PTV. Most LFs (92.9%) would have been encompassed by the Radiation Therapy Oncology Group consensus target volumes.

Conclusions

After adjuvant pancreatic SBRT for close/positive margins, the majority of LFs were outside the PTV but within contemporary target volumes for conventional radiation therapy.

Abstract CT201: Phase Ib/II open-label, randomized evaluation of atezolizumab + cobimetinib vs control in MORPHEUS-NSCLC (non-small cell lung cancer), MORPHEUS-PDAC (pancreatic ductal adenocarcinoma) and MORPHEUS-GC (gastric cancer)

Background: The MORPHEUS platform comprises multiple Phase Ib/II trials to identify early efficacy signals and safety of treatment combinations across cancers. Within MORPHEUS, atezolizumab (atezo), a PD-L1 inhibitor, was tested in combination with cobimetinib (cobi), a MEK1/2 inhibitor, in patients with advanced/metastatic (m) NSCLC, PDAC or GC. Methods: MORPHEUS-NSCLC (NCT03337698) enrolled patients who had disease progression during or after receiving a platinum-based regimen and a PD-L1/PD-1 checkpoint inhibitor. MORPHEUS-PDAC (NCT03193190) enrolled patients who had received 1 prior line of systematic therapy. MORPHEUS-GC (NCT03281369) enrolled HER2-negative patients who had not received prior chemotherapy. Patients enrolled in the atezo + cobi arms received atezo 840 mg q2w and cobi 40 mg daily on days 1-21 of each 28-day cycle. In MORPHEUS-GC, patients in the atezo + cobi arm also received mFOLFOX6. This arm started with a safety run-in during which cobi 40 mg could be dose escalated to 60 mg. Control treatments were docetaxel (75 mg/m2) in MORPHEUS-NSCLC and mFOLFOX6 or gemcitabine (100 mg/m2) plus nab-paclitaxel (125 mg/m2) in MORPHEUS-PDAC. The MORPHEUS-GC safety run-in did not have a control. Primary endpoints were objective response rate (ORR; investigator-assessed RECIST 1.1) and safety. Results: MORPHEUS-NSCLC (data cutoff, April 10, 2019): 15 patients received atezo + cobi, and 14 patients received control treatment. No responses were observed, and 7 patients had stable disease (SD) as best response in the treatment arm. In the control arm, 3 patients had partial response (PR), and 5 patients had SD as confirmed best response. All treated patients were evaluable for safety, with 67% of atezo + cobi and 93% of control patients experiencing a treatment-related adverse event (TRAE). Updated data from MORPHEUS-NSCLC will be presented. MORPHEUS-PDAC (data cutoff, September 7, 2018): 14 patients received atezo + cobi, and 15 patients received control treatment. There were no responses in either study arm, but 6 patients in the control arm had SD as confirmed best response. All treated patients were evaluable for safety, with 79% of atezo + cobi and 87% of control patients experiencing a TRAE. MORPHEUS-GC (data cutoff, July 11, 2019): 5 patients received atezo + cobi + mFOLFOX6 in the safety run-in after which this arm was terminated (due to internal re-prioritization, no safety concerns identified). Two patients had PR, and 3 patients had SD as confirmed best response. All 5 patients had a TRAE. Biomarker data will also be presented. Conclusions: No superior efficacy signals were identified with atezo + cobi in NSCLC, PDAC or GC. The safety of atezo + cobi was consistent with each agent's known safety profile, with no new safety signals identified.

Citation Format: Byoung Chul Cho, Nathan Bahary, Johanna Bendell, Enriqueta Felip, Melissa Johnson, Yoon-Koo Kang, Farah Louise Lim, Teresa Macarulla, Gulam Manji, Do-Youn Oh, Osama Rahma, Simon Allen, Edward Cha, Denise Cotting, Hans-Joachim Helms, Jan Pintoffl, Pakeeza Sayyed, Xiaosong Zhang, Kyu-pyo Kim. Phase Ib/II open-label, randomized evaluation of atezolizumab + cobimetinib vs control in MORPHEUS-NSCLC (non-small cell lung cancer), MORPHEUS-PDAC (pancreatic ductal adenocarcinoma) and MORPHEUS-GC (gastric cancer) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT201.

Randomized Phase III Trial of Pegvorhyaluronidase Alfa With Nab-Paclitaxel Plus Gemcitabine for Patients With Hyaluronan-High Metastatic Pancreatic Adenocarcinoma

PURPOSE

To evaluate the efficacy and safety of pegvorhyaluronidase alfa (PEGPH20) plus nab-paclitaxel/gemcitabine (AG) in patients with hyaluronan-high metastatic pancreatic ductal adenocarcinoma (PDA).

PATIENTS AND METHODS

HALO 109-301 was a phase III, randomized, double-blind, placebo-controlled study. Patients ≥ 18 years of age with untreated, metastatic, hyaluronan-high PDA were randomly assigned 2:1 to PEGPH20 plus AG or placebo plus AG. Treatment was administered intravenously in 4-week cycles (3 weeks on, 1 week off) until progression or intolerable adverse events: PEGPH20 3.0 µg/kg twice per week for cycle 1 and once per week thereafter; nab-paclitaxel 125 mg/m² once per week; and gemcitabine 1,000 mg/m² once per week. The primary end point was overall survival (OS); secondary end points included progression-free survival (PFS), objective response rate (ORR), and safety. Response was independently assessed per RECIST v1.1.

RESULTS

At data cutoff, 494 patients were randomly assigned, with 492 (327 for PEGPH20 and 165 for placebo) included in intention-to-treat analyses. Baseline characteristics were balanced for PEGPH20 plus AG versus placebo plus AG. There were 330 deaths, with a median OS of 11.2 months for PEGPH20 plus AG versus 11.5 months for placebo plus AG (hazard ratio [HR], 1.00; 95% CI, 0.80 to 1.27; P = .97); median PFS was 7.1 months versus 7.1 months (HR, 0.97 [95% CI, 0.75 to 1.26]); ORR was 47% versus 36% (ORR ratio, 1.29 [95% CI, 1.03 to 1.63]). Grade ≥ 3 adverse events with a ≥ 2% higher rate with PEGPH20 plus AG than with placebo plus AG included fatigue (16.0% v 9.6%), muscle spasms (6.5% v 0.6%), and hyponatremia (8.0% v 3.8%).

CONCLUSION

The addition of PEGPH20 to AG increased the ORR but did not improve OS or PFS. The safety profile of PEGPH20 plus AG was consistent with that found in previous studies. These results do not support additional development of PEGPH20 in metastatic PDA.

A multicenter chart review study of patients with metastatic pancreatic ductal adenocarcinoma receiving liposomal irinotecan after gemcitabine-based therapy

e16733

Background: Real-world data allows healthcare decision-makers to assess and manage therapeutic and economic options for patients, including those who would and would not have met eligibility criteria for randomized control trials (RCT) and are instead managed under usual care. This retrospective multi-academic center chart review study describes real-world characteristics and outcomes of US patients receiving liposomal irinotecan for the management of metastatic pancreatic ductal adenocarcinoma (mPDAC). Methods: Patients with mPDAC treated with liposomal irinotecan were eligible. Initiation of liposomal irinotecan defined index date; covariates assessed included clinical characteristics and treatment patterns; real-world overall survival (rwOS) was assessed via Kaplan-Meier methodology. The target enrollment is 300 patients. The study centers included were Memorial Sloan Kettering Cancer Center, Cedars-Sinai Medical Center, Emory Winship Cancer Institute, Houston Methodist Cancer Center, Henry Ford Cancer Institute, and University of Pittsburgh Medical Center. Results: Data on 26 patients were available for initial analyses. Mean age was 68 years; 58% were female and 65% Caucasian. 54% of patients had stage IV disease at first diagnosis, and 17%, 65%, and 17% had index ECOG score of 0, 1, and 2, respectively. Common genetic mutations include KRAS (40%) and TP53 (40%). Prior to liposomal irinotecan, treatments received for metastatic disease include gemcitabine+nab-paclitaxel (77%) and fluorouracil (5-FU)/leucovorin (LV)+irinotecan+oxaliplatin (19%). Patients had received 0 (12%), 1 (23%), and ≥2 (65%) lines of therapy in the metastatic setting prior to liposomal irinotecan. Mean duration of liposomal irinotecan use was 3.0 months; liposomal irinotecan was mostly received with 5-FU (23%) or 5-FU/LV (69%). Median rwOS was 4.9 months (95% CI: 3.0, 6.3). Conclusions: Real-world data of the first 26 patients in this study show patients treated with liposomal irinotecan are older, sicker, and have had more lines of therapy than previously reported in RCT data.

A phase II/III study of perioperative nivolumab and ipilimumab in patients (pts) with locoregional esophageal (E) and gastroesophageal junction (GEJ) adenocarcinoma: A trial of the ECOG-ACRIN Cancer Research Group (EA2174)

TPS4651

Background: E/GEJ adenocarcinoma has a high mortality rate despite curative intent treatment. A pathologic complete response (pCR) is associated with better overall survival (OS) but occurs in less than 30% of pts. Immunotherapy is effective in the metastatic setting. Here we aim to evaluate the contribution of immunotherapy in the neoadjuvant and adjuvant settings in pts with locoregional E/GEJ cancer. Methods: This is a multi-center, randomized phase II/III trial. Surgical candidates with locoregional E/GEJ adenocarcinoma receive carboplatin AUC 2 IV and paclitaxel 50 mg/m2 IV, both weekly x 5 during concurrent radiation (50.4 Gy) either with or without nivolumab 240 mg IV during weeks 1 and 3, followed by surgery. Pts with no post-operative disease receive nivolumab 240 mg IV every 2 weeks for 12 cycles either with or without ipilimumab 1 mg/kg IV every 6 weeks for 4 cycles. Eligibility criteria include pts with T1-N1-3M0 or T2-3N0-2M0 disease whom are candidates for surgery, no prior chemotherapy or radiation for this disease, no prior immunotherapy, no significant autoimmune disease. Pts must be disease free for adjuvant treatment. Primary neoadjuvant endpoint is pCR rate; primary adjuvant endpoint is disease free survival (DFS). Secondary endpoints include toxicity, DFS and OS. Pre- and mid-treatment diffusion weighted imaging MRI will be conducted during the neoadjuvant portion of the study. A neoadjuvant safety run in of 30 pts is underway. Overall, 278 pts will be needed to detect an absolute improvement of 15% in pCR rate in pts receiving and not receiving neoadjuvant nivolumab and 236 pts will be needed to detect a HR of 0.65 in favor of adjuvant ipilimumab/nivolumab over nivolumab (90% power, one sided alpha of 0.10). Accrual is expected over 34 months at a rate of 8 patients per month. If favorable at interim analysis. Clinical trial information: NCT03604991 .

A Randomized Phase II Preoperative Study of Autophagy Inhibition with High-Dose Hydroxychloroquine and Gemcitabine/Nab-Paclitaxel in Pancreatic Cancer Patients

PURPOSE

We hypothesized that autophagy inhibition would increase response to chemotherapy in the preoperative setting for patients with pancreatic adenocarcinoma. We performed a randomized controlled trial to assess the autophagy inhibitor hydroxychloroquine in combination with gemcitabine and nab-paclitaxel.

PATIENTS AND METHODS

Participants with potentially resectable tumors were randomized to two cycles of nab-paclitaxel and gemcitabine (PG) alone or with hydroxychloroquine (PGH), followed by resection. The primary endpoint was histopathologic response in the resected specimen. Secondary clinical endpoints included serum CA 19-9 biomarker response and margin negative R0 resection. Exploratory endpoints included markers of autophagy, immune infiltrate, and serum cytokines.

RESULTS

Thirty-four patients in the PGH arm and 30 in the PG arm were evaluable for the primary endpoint. The PGH arm demonstrated statistically improved Evans grade histopathologic responses (P = 0.00016), compared with control. In patients with elevated CA 19-9, a return to normal was associated with improved overall and recurrence-free survival (P < 0.0001). There were no differences in serious adverse events between arms and chemotherapy dose number was equivalent. The PGH arm had greater evidence of autophagy inhibition in their resected specimens (increased SQSTM1, P = 0.027, as well as increased immune cell tumor infiltration, P = 0.033). Overall survival (P = 0.59) and relapse-free survival (P = 0.55) did not differ between the two arms.

CONCLUSIONS

The addition of hydroxychloroquine to preoperative gemcitabine and nab-paclitaxel chemotherapy in patients with resectable pancreatic adenocarcinoma resulted in greater pathologic tumor response, improved serum biomarker response, and evidence of autophagy inhibition and immune activity.

Prognostic Value of the Systemic Immune-Inflammation Index (SII) After Neoadjuvant Therapy for Patients with Resected Pancreatic Cancer

BACKGROUND

The systemic immune-inflammation index (SII), calculated using absolute platelet, neutrophil, and lymphocyte counts, has recently emerged as a predictor of survival for patients with pancreatic ductal adenocarcinoma (PDAC) when assessed at diagnosis. Neoadjuvant therapy (NAT) is increasingly used in the treatment of PDAC. However, biomarkers of response are lacking. This study aimed to determine the prognostic significance of SII before and after NAT and its association with the pancreatic tumor biomarker carbohydrate-antigen 19-9 (CA 19-9).

METHODS

This study retrospectively analyzed all PDAC patients treated with NAT before pancreatic resection at a single institution between 2007 and 2017. Pre- and post-NAT lab values were collected to calculate SII. Absolute pre-NAT, post-NAT, and change in SII after NAT were evaluated for their association with clinical outcomes.

RESULTS

The study analyzed 419 patients and found no significant correlation between pre-NAT SII and clinical outcomes. Elevated post-NAT SII was an independent, negative predictor of overall survival (OS) when assessed as a continuous variable (hazard ratio [HR], 1.0001; 95% confidence interval [CI] 1.00003-1.00014; p = 0.006). Patients with a post-NAT SII greater than 900 had a shorter median OS (31.9 vs 26.1 months; p = 0.050), and a post-NAT SII greater than 900 also was an independent negative predictor of OS (HR, 1.369; 95% CI 1.019-1.838; p = 0.037). An 80% reduction in SII independently predicted a CA 19-9 response after NAT (HR, 4.22; 95% CI 1.209-14.750; p = 0.024).

CONCLUSION

Post-treatment SII may be a useful prognostic marker in PDAC patients receiving NAT.