The impact of inflammatory biomarkers, BMI, and sarcopenia on survival in advanced hepatocellular carcinoma treated with immunotherapy

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Background: Sarcopenia and inflammation are independently associated with worse survival in cancer patients. This study aims to determine the impact of inflammatory biomarkers, BMI and sarcopenia on survival in advanced hepatocellular carcinoma (HCC) patients treated with immunotherapy. Methods: We performed a retrospective review of advanced HCC patients treated with immunotherapy-based therapies at Winship Cancer Institute between 2015 and 2019. Baseline computed tomography and magnetic resonance imaging scans were collected at mid-L3 level, assessed for skeletal muscle density using SliceOmatic (TomoVision, version 5.0) and converted to skeletal muscle index (SMI) by dividing it by height (m)2. Gender-specific sarcopenia was defined by median value of SMI. The optimal cut for continuous inflammation biomarker was determined by bias-adjusted log-rank test. Overall Survival (OS) was set as primary outcome and Cox proportional hazard model was performed. Results: 57 patients were included; 77.2% male, 52.6% Caucasian, 58.5% ECOG PS 0-1, 80.7% Child Pugh A. Treatment was second line and beyond in 71.9%. The median follow-up time was 6 months. Sarcopenia cut-off for males and females was SMI of 43 and 39, respectively. 49.1% of patients had sarcopenia. Median OS was 5 vs. 14.3 months in sarcopenic vs. non-sarcopenic patients (p=0.054). Median OS was 5 and 17.5 months in patients with BMI <25 and BMI ≥25 respectively (p=0.034). Median OS was 3.6 and 14.3 months for patients with neutrophil to lymphocyte ratio (NLR) ≥ 5.15 vs. NLR < 5.15 (p<0.001). In multivariable Cox regression model, higher baseline NLR was associated with worse OS (HR: 4.17, 1.52-11.39, p=0.005). Gender specific sarcopenia showed a trend of worse OS (HR: 1.71, 0.73-4.00, p=0.215) but was not statistically significant. BMI<25 was associated with worse OS (HR: 2.73, 1.15-6.53, p=0.023). In the association with PFS, neither baseline BMI nor gender specific sarcopenia showed statistical significance. Conclusions: Baseline BMI and NLR may predict OS after immunotherapy treatment. After controlling for baseline Child Pugh Score and NLR, gender specific sarcopenia was not associated with OS significantly.

Evaluation of Ki67 and other predictors of survival in metastatic neuroendocrine tumor (NET) to the liver treated with Y90 radioembolization

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Background: Ki67 index is a predictor of survival in patients with metastatic neuroendocrine tumor (NET). The purpose of this study is to evaluate Ki67 index and other potential predictors of overall survival (OS) in patients with NET metastases to the liver treated with Y90 radioembolization. Methods: In an institutional review board-approved retrospective study, consecutive patients with NET metastases to the liver who were treated with Y90 radioembolization from 2013-2018 at a single institution were evaluated. Patients with documented Ki67 index were stratified according to 2017 World Health Organization (WHO) grading based on Ki67 index (G1: < 3%, G2: 3-20%, G3: > 20%). Age, gender, and objective tumor response on post Y90 imaging were also evaluated as potential predictors of survival after Y90. Objective tumor response was evaluated at 1 and/or 3 months post Y90 with multiphase MRI utilizing Response Evaluation Criteria for Solid Tumors (RECIST). Overall survival (OS) from time of Y90 was analyzed using Kaplan-Meier estimation. Predictors of survival were evaluated using log-rank test with p < 0.05 as the statistically significant level. SPSS software v. 25 (IBM Corporation, Armonk, NY) was used for all statistical analysis. Results: A total of 77 patients were identified; 36 (47%) had a documented Ki67 index from either their primary tumor, liver metastasis, or both. Primary tumor site included pancreatic (n = 10), small bowel (n = 7), pulmonary (n = 5), gastric (n = 3), large bowel (n = 3), and renal (n = 1). A primary site was not identified in several patients (n = 7).G1 tumors comprised 31% (n = 11) of patients, while G2 and G3 tumors made up 50% (n = 18) and 19% (n = 7) of the cohort, respectively. Median overall survival (OS) of the entire cohort was 51.1 months. Median OS in patients was 63.0 months in G1 tumors, 51.1 months in G2 tumors, and 3.1 months in G3 tumors (p < 0.001). Objective response on initial MRI follow-up after Y90 radioembolization also predicted prolonged OS (51.2 months versus 17.9 months, p < 0.001). Age at time of diagnosis and gender were not predictors of survival after Y90 radioembolization. Conclusions: WHO grading based on KI67 index and objective tumor response appear to be predictors of prolonged survival in patients with metastatic NET to the liver treated with Y90 radioembolization.

Predictors of survival in chemorefractory colorectal liver metastases treated with Y90 radioembolization

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Background: The aim of the study was to evaluate molecular signatures and timing of yttrium-90 (Y90) as prognostic factors of survival following Y90 radioembolization (RE) in patients with chemorefractory colorectal liver metastases (CRLM). Methods: In a retrospective single-institution study, patients with unresectable, chemorefractory CRLM who had undergone genomic analysis prior to Y90 RE from 2013 to 2018 were identified. Timing of Y90 (following failure of first line vs following multiple lines of chemotherapy) and oncogenic mutation status (MAPK and PI3K pathways) were evaluated as predictors of survival length following Y-90. Survival was measured from first Y90 using Kaplan-Meier estimation and predictors of outcome were identified using log-rank analysis. Results: Overall, 58 patients with chemorefractory CRLM who underwent genomic analysis prior to Y-90 were identified. Of these, 26 (44.8%) had MAPK mutations, and 2 (3.5%) had PI3K mutations. Median survival after first Y-90 RE was 12.9 months. There was significantly prolonged overall survival (OS) in patients receiving Y90 immediately following failure of the first line of chemotherapy (FOLFOX ± bevacizumab) versus patients who underwent multiple lines of chemotherapy prior to Y90 (median OS of 16.9 vs 11.4 months for others; p = 0.023). When stratifying the cohort based on the timing of Y90, patients with WT-MAPK (n = 8) had prolonged OS if they underwent Y-90 following failure of the first line of chemotherapy (median OS of 22.3 vs 12.9 mo; p = 0.019). Patients with WT-PI3K (n = 19) had prolonged OS if they underwent Y90 following failure of the first line of chemotherapy (median OS of 16.9 vs 12 mo; p = 0.037). When analyzing the entire cohort non-stratified by timing of Y90, genetic mutation was not found to be a predictor of prolonged OS. Conclusions: Y90 RE after failure of first line of chemotherapy in CRLM appears to confer prolonged survival specifically for WT-MAPK and WT-PI3K oncogenes. Conversely, the prognosis of more favorable genetic status appears to be negated if Y90 RE is performed after failure of second or third line chemotherapies.

Analysis of age, tumor-sidedness, and mismatch repair (MMR) genes with response to immune checkpoint inhibitors (ICIs) in MMR-deficient (dMMR) colorectal cancer (CRC) patients (pts): A multi-institutional study

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Background: ICIs induce durable responses in dMMR CRC pts with overall response rates (ORR) of 30-50%. Even though the loss of expression of any MMR gene predicts ICIs response, it is unknown if ORRs are similar across all MMR genes (MLH1, PMS2, MSH2, and MSH6). In this study, we analyzed the impact of each specific MMR gene loss and clinical characteristics of pts with best response to ICIs. Methods: Pts were eligible if they had confirmed dMMR CRC by IHC or microsatellite instability-high (MSI-H) by PCR, and received ICIs between 01/01/2012 and 10/01/2018 at Winship Cancer Institute of Emory University, Mayo Clinic or Vanderbilt University Medical Center. Due to the pattern of frequent concurrent loss and functional dependency, the groups were categorized as MLH1 ±PMS2 vs. MSH2 ±MSH6. Cox proportional hazard model and Fisher’s exact test were used for the best response and the distribution of variable among the subgroups. Results: A total of 45 pts with dMMR CRC were identified. ORRs in MLH1 ±PMS2 and MSH2 ±MSH6 groups were 68% and 57.1% respectively without statistical difference (Table). Pts with age < 50 and 50-65 years old had better ORRs compared to pts with age >65 (58.3%, 85.7% and 42.1% respectively, P=0.036). Left-sided tumors had a trend toward higher ORRs compared to right-sided tumors (83.3% vs 51.5% P=0.086). Gender and BRAF status were not predictors of response. BRAF mutations were more common in right-sided tumors (29.6% vs 11.1% respectively) and in older patients. Conclusions: Our data suggest that MSI-H CRC pts aged 50-65 treated with ICIs, have improved ORR compared to pts > 65; pts with left-sided tumors have a trend toward improved ORR compared to those with right sided tumors. [Table: see text]

Derazantinib (DZB) provides antitumor efficacy regardless of line of therapy in patients (pts) with FGFR2-fusion positive advanced intrahepatic cholangiocarcinoma (iCCA)

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Background: FGFR2 fusions are prevalent in 13-22% of iCCA and known oncogenic drivers. DZB is a kinase inhibitor with potent pan-FGFR activity. In a non-comparative Phase 2a study, DZB was administered to 29 pts with FGFR2-fusion positive advanced, inoperable iCCA, either as first-line (1L) (n = 2), 2L (n = 13), 3L (n = 10), 4L (n = 2) or 5L therapy (n = 2). The objective response rate (ORR) with DZB was 21%, disease-control rate (DCR) 83% and median PFS 5.7 months (Mazzaferro et al. 2018 BJC). Data from biliary tract cancer studies suggest decreasing treatment effects of chemotherapy with increasing lines of treatment. Here, we present a post-hoc analysis of outcomes of pts treated with DZB in 1L/2L (n = 15) compared to pts treated post-2L (n = 14). Methods: Pts received 300 mg DZB QD PO. Eligibility criteria included locally confirmed, positive testing of FGFR2 fusion expression (FISH or NGS), ECOG PS 0-1. Objective responses were determined using RECIST 1.1. Disease control rate was defined as CR, PR or SD. Results: The mean age of pts treated in 1L/2L was 66y and 55y in post-2L; 73% were females in 1L/2L and 50% in post-2L treatment; other demographic variables were balanced between groups (87% vs 86% of liver target lesions, median baseline lesion size of 97.5 mm vs 109.5 mm, ECOG PS0 was 60% vs 71%). Of 15 1L/2L group pts, 12 (80%) had prior platinum-based chemotherapy as compared to all 14 pts in the post-2L group. In the 1L/2L and post-2L groups, ORR was 20% and 21%, DCR was 80% and 86%, and a reduction in sum of the largest diameter of target lesions was observed in 60% and 64% of pts, respectively. Median PFS was 5.5 mo (95% CI, 1.9-11.9) and 6.2 mo (3.6-9.2) for the 1L/2L and post-2L groups, respectively. Types of drug-related adverse events were similar in 1L/2L and post-2L. Conclusions: Anti-tumor efficacy of DZB in iCCA patients measured either by ORR, DCR, tumor shrinkage or PFS was numerically similar irrespective of treatment line. These data suggest that DZB is an effective treatment option that can be applied early in the treatment continuum of iCCA patients or at later stages to offer anti-tumor efficacy and disease control. Clinical trial information: 01752920.

Role of resection of the primary in metastatic well/intermediate-differentiated neuroendocrine tumor (NET)

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Background: Resection of the primary tumor in metastatic neuroendocrine tumor (NET) is controversial. The aim of this study is to evaluate survival outcomes and identify prognostic variables of surgical resection of the primary tumor in metastatic NET patients. Methods: Data were obtained from all US hospitals that contributed to the National Cancer Database (NCDB) between 2004 and 2013. Chi-square and ANOVA tests were done to identify factors associated with surgical modality. Univariate and multivariate cox proportional hazards models were used for association between patient characteristics and survival. Kaplan-Meier curves were generated and log-rank tests conducted to compare the survival difference of patient characteristics. Results: A total of 2,361 patients between 18 and 90 years of age with stage IV well/intermediate-differentiated NET were identified. The mean age was 62.1 years (SD±13), with an equal male to female ratio (50.0%). Majority of NET primaries were in the small intestine (33.0%), pancreas (26.3%), and lung (24.4%). The majority were well differentiated tumors (69.6%) and 42.5% of patients underwent surgery at the primary site. On multivariate analysis total surgical resection of the primary (HR 0.44; 0.22-0.90; p < 0.001), female sex, year of diagnosis 2010-2014, negative surgical margin, Charlson-Deyo score < 2, and age < 51 years at diagnosis were associated with better overall survival (OS). Conclusions: Resection of the primary in stage IV well/intermediate-differentiated NET was associated with improved 5-year OS compared to patients with no surgery in small intestine (60.1% vs 44.2%), lung (70.0% vs 20.2%), and pancreas tumors (59.3% vs 30.6%).

Blood-based next-generation sequencing analysis of neuroendocrine tumors

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Background: Neuroendocrine tumors (NET) comprise around 2% of all malignant tumors of the gastrointestinal system. The genomic landscape of NET has not been well studied. The aim of this study was to confirm the feasibility of next generation sequencing (NGS) using ctDNA in NET and characterize common alterations in the genomic profile. Methods: Molecular alterations in 114 plasma samples from 114 patients with NET using clinical-grade NGS of ctDNA (Guardant360Ò) across multiple institutions were evaluated. The test detects single nucleotide variants in 54-73 genes, copy number amplifications, fusions, and indels in selected genes. Results: A total of 114 NET patients were evaluated, of which 64 (56.1%) were female. Mean age was 59.7 years with a range between 23-89 years. ctDNA NGS testing was performed on 114 plasma samples; 1 patient had testing performed twice. Genomic alterations were defined in 94 (n = 94/114, 82.5%) samples with a total of 289 alterations identified after excluding variants of uncertain significance (VUSs) and synonymous mutations. Alterations were identified in at least one sample from 83 patients; TP53 associated genes were most commonly altered (n = 83/289, 28.7%), followed by KRAS (n = 22, 7.6%), PI3CA (n = 15, 5.2%), CCNE1 (n = 15, 5.2%), BRAF (n = 13, 4.5%), MYC (n = 12, 4.1%), ERBB2 (n = 11, 3.8%), APC (n = 10, 3.5%), EGFR (n = 10, 3.5%), MET (n = 10, 3.5%), PTEN (n = 9, 3.1%), RB1 (n = 9, 3.1%), CDK6 (n = 7, 2.4%), AR (n = 5, 1.7%), ARID1A (n = 5, 1.7%), FGFR1 (n = 5, 1.7%), and PDGFRA (n = 5, 1.7%). Other genomic alterations of low frequency, but clinical relevance included: CDK4 (n = 4, 1.3%), NF1 (n = 4, 1.3%), RAF1 (n = 4, 1.3%), GNAS (n = 3, 1.0%), KIT (n = 3, 1.3%), BRCA2 (n = 2, 0.7%), CCND2 (n = 2, 0.7%), CTNNB1 (n = 2, 0.7%), JAK2 (n = 2, 0.7%), NRAS (n = 2, 0.7%), SMAD4 (n = 2, 0.7%), and TERT (n = 2, 0.7%). Alterations in AKT1, ALK, ATM, BRCA1, CCND1, CDKN2A, FGFR2, MTOR, RHOA, SMO and STK11 were all reported once (n = 1, 0.3%). Conclusions: Evaluation of ctDNA is feasible among individuals with NET. Liquid biopsies are not invasive and can provide personalized options for targeted therapies in NET patients.

Perioperative therapy in patients with metastatic colorectal cancer

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Background: Knowledge about perioperative systemic therapy in metastatic colorectal cancer (mCRC) is limited. We aim to describe the nationwide pattern of use and survival outcomes of patients with mCRC treated with surgical resection. Methods: Data were obtained from all US hospitals that contributed to the National Cancer Database (NCDB) between 2004 and 2013. Univariate and multivariate analyses was done to identify factors associated with patient outcome. Results: A total of 61,940 patients with stage IV CRC older than 18 years were identified. Mean age was 63.4 years (SD±14), with a male preponderance (54.8%). About 80% were Caucasian and 69.9% had colon cancer. Compared to medical treatment only, resection of both primary and metastatic sites (13.5%; HR 0.40; 0.37-0.44; p < 0.001), or primary site resection alone (49.2%; HR 0.52; 0.48-0.56; p < 0.001) were associated with improved overall survival (OS). Other co-variates associated with improved survival included younger age group, year of diagnosis (2009-2013), colon tumor location, and < 3 metastatic sites (Table). Five-year OS for resection of primary and metastatic site (28.2%) was higher than for primary site resection alone (14.9%) or no surgical treatment (4.7%). Conclusions: Resection of metastatic sites or primary tumor was associated with improved survival in patients with stage IV CRC.[Table: see text]

Genomic alterations in appendiceal carcinoma using circulating DNA

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Background: Appendiceal cancers (AC) comprise around 0.5% of all gastrointestinal neoplasia. The genomic landscape of AC has not been well studied. The yield of circulating tumor DNA (ctDNA) from the plasma of patients with AC has not been reported. The aim of this study is to confirm the feasibility of NGS using ctDNA and characterize common alternations in the genomic profile of AC. Methods: The molecular alterations in 372 plasma samples from 303 patients with AC using clinical-grade NGS of ctDNA (Guardant 360) across multiple institutions, was evaluated. The test detects single nucleotide variants in 54 -73 genes, copy number amplifications, fusions, and indels in selected genes. Results: A total of 303 AC patients were evaluated; 169 female (56%). Median age was 56.8 (range: 25-83). ctDNA NGS testing was done on 372 plasma samples; 48 patients had testing performed twice, 9 three times, and 1 was tested four times. Genomic alterations were defined in 207 (55.6%) samples with a total of 288 alterations identified after excluding variants of uncertain significance (VUSs) and synonymous mutations. TP53 associated genes were most commonly altered (n = 96, 33.3%), followed by KRAS (n = 41, 14.2%), APC (n = 19, 6.6%), EGFR (n = 15, 5.2%), BRAF (n = 13, 4.5%), NF1 (n = 13, 4.5%), MYC (n = 9, 3.1%), GNAS (n = 8, 2.7%), PI3CA (n = 7, 2.4%), MET (n = 6, 2.08%), ATM in 6 (1.6%). Other genomic alterations of low frequency, but clinically relevant: AR (n = 4, 1.39%), TERT (n = 4, 1.39%), ERBB2 (n = 4, 1.39%), SMAD4 (n = 3, 1.04%), CDK4 (n = 2, 0.69%), NRAS (n = 2, 0.69%), FGFR1 (n = 2, 0.69%), FGFR2 (n = 2, 0.69%), PTEN (n = 2, 0.69%), RB1 (n = 2, 0.69%), and CDK6, CDKN2A, BRCA1, BRCA2, JAK2, IDH2, MAPK, NTRK1, CDH1, ARID1A, and PDGFRA were all reported once. Conclusions: Evaluation of ctDNA was feasible among individuals with AC. The frequency of genomic alterations in ctDNA testing is similar to those previously reported in tissue NGS. Liquid biopsies are non-invasive methods that can provide personalized options for targeted therapies in patients with AC.

Impact of genomic alterations (GAs) on outcomes and their distribution by age groups in metastatic colorectal cancer (mCRC) patients (pts)

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Background: Although clinical outcomes has substantially improved over the last decade, long term survival in mCRC remains rare. Molecular profiling (MP) of CRC is routinely conducted to identify potential therapeutic targets. The aim of this project is to evaluate the impact of uncommon GAs on outcomes and characterize their distribution by age. Methods: Pts were eligible if they had mCRC (synchronous or metachronous) and underwent MP between 01/2013 and 05/2018. GAs were obtained from Foundation Medicine reports. Clinical data were collected by trained personnel by detailed chart review. Multivariable survival analyses (MA) with Cox model were conducted for survival outcomes and Fisher’s exact test was used to assess the differences among age groups (< 45, 45-60, > 60). The study was reviewed by Institutional IRB ( IRB00097021 ). Results: 161 patients with mCRC had MP, and 159 of those patients had survival data. The most commonly detected GAs were APC (133/161, 82.6%) TP53 (128/161, 79.5%). In univariate analyses mutations in BRCA 1/2, RB1, SOX9, CDK8, FLT3, and IRS2 amplification were associated with worse survival outcomes. In MA, including initial stage of disease, GAs in BRCA1/2, RB1, FLT3, SOX9, and IRS2 remained statistically significant (Table). When we performed MA by age groups, mutations SOX9 in age group < 45 and BRCA1/2 in age group 45-60 were significant predictors of worse outcomes. We also compared the frequency of mutations among age groups and FAM123B was significantly more common in age group 45-60 (P = 0.038). Conclusions: Our data suggests that GAs in BRCA1/2, RB1, FLT3, SOX9, and IRS2 may predict worse outcomes in mCRC. Therapeutic approaches targeting these pathways should be investigated. Differences in distribution and prognostic significance of mutations were observed based on age. [Table: see text]

Phase II randomized, double-blind, study of mFOLFIRINOX plus ramucirumab versus mFOLFIRINOX plus placebo in advanced pancreatic cancer patients hcrn GI14-198

TPS475

Background: The prognosis of pancreas adenocarcinoma (PCA) remains poor. A chemotherapy backbone is the current standard of care in PCA. The choice of a chemotherapeutic backbone may impact the efficacy of anti-angiogenic therapy in PCA. Ramucirumab has increased activity with fluoropyrimidines (5FU) because 5FU increases VEGF expression. Methods: This is a double-blind, placebo controlled Phase II study. Subjects will receive either Ramucirumab or a placebo followed by mFOLFIRINOX every two weeks of a 28 day cycle until progression or discontinuation for other reasons. The primary endpoint of this clinical trial is nine month PFS defined as the time from enrollment to the time of progression or death. Among the key inclusion criteria, subjects must have recurrent or metastatic pancreas adenocarcinoma (PCA) with no prior first-line systemic treatment, ECOG PS 0-1, adequate organ function, no DVT, PE or other thromboembolism within three months of randomization. Total number of patient enrolled as of September 19, 2018 is 48 of 85 at eight sites; 27 male (56%), 42 Caucasians (87.5%), three African American (6.2%), one Asian (2%). Median age is 63 (40 - 76). Majority of patients (41) had de novo metastatic disease and six with recurrent disease after surgery. Regimen has been tolerated well with no unanticipated events. Clinical trial information: NCT02581215.

Clinical outcomes of hepatocellular carcinoma variants compared to hepatocellular carcinoma

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Background: There is no consensus regarding treatment for HCC variants. Clinical outcomes of HCC variants differ from pure HCC. The aim of this study is to compare clinicopathological characteristics, treatment, and outcomes of HCC variants with pure HCC. Methods: Patients with HCC and variants with 8170/3-8175/3 and 8180/3 ICD-O-3 codes were identified from National Cancer Database between 2004 and 2013. Univariate and multivariate survival analyses were conducted to analyze the association between histology and overall survival (OS). Results: 80,280 patients were identified; pure HCC 78,461 (97.7%), fibrolamellar (FLHCC) 310 (0.4%), scirrhous 161 (0.2%), spindle cell 72 (0.1%), clear cell 487 (0.6%), pleomorphic 23 (0.0%), and combined HCC and cholangiocarcinoma (mixed HCC) 766 (1.0%). 76.7% were male and 72% Caucasian. The mean age was similar in all except FLHCC (37.9 vs. 60.9-64.1 years, p < 0.001). Liver transplant was performed in 10.1% of pure HCC, 14.5% of mixed HCC, 16.2% of scirrhous, 6.9% of spindle cell, 8.8% of clear cell, 8.7% of pleomorphic, and 3.2% of FLHCC (p < 0.001). Pure HCC (10.57%) underwent surgical resection less often than variants; FLHCC (54.8%), clear cell (34.5%), mixed HCC (29.8%), spindle cell (33.3%), pleomorphic (34.8%), and scirrhous (9.9%) (p < 0.001). Ablation was performed in 9.8% of pure HCC, and in up to 8.7% of HCC variants. More than a third of all patients received chemotherapy; pure HCC (42.3%), mixed HCC (38.5%), scirrhous (31.1%), spindle cell (36.1%), clear cell (35.5%), pleomorphic (34.8%), and FLHCC (41.3%). FLHCC had the best 5-year OS (38.7%), spindle cell and pleomorphic had the worst (9.6% and 13.0%). In univariate and multivariate analyses, fibrolamellar histology, female sex, diagnosis between 2009 and 2013, treatment at academic center, well/moderately differentiated histology, early stage, and chemotherapy was associated with better OS compared to pure HCC, male sex, diagnosis between 2004 and 2008, treatment at community cancer program, poorly differentiated, late stage, and no chemotherapy (p < 0.001). Conclusions: HCC variants underwent surgical resection more often than HCC. FLHCC had the best 5-year OS. Liver transplant is commonly performed in HCC variants.

Altering the cytokine profile in the pancreatic cancer microenvironment with heat shock protein-90 inhibitors to enhance immunotherapy

One feature of pancreatic ductal adenocarcinoma (PDAC) is the fibrotic stroma, which is a result of interactions between tumor cells, immune suppressive cells and pancreatic stellate cells (PSC). Stroma-derived cytokines including IL-6 represent a significant barrier restraining immunity against PDAC. Targeting pathways in the tumor microenvironment (TME) that regulate cytokine secretion can be an innovative means to improve access of effector immune cells to PDAC. We hypothesize that targeting Hsp90 can modulate the TME, through its ability to target inflammatory signaling and cytokine production by PSC and enhance the efficacy of immunotherapy. The Hsp90 inhibitor XL888 led to a concentration-dependent inhibition of IL-6 and MCP-1 production by PSC in vitro. Concurrently, PSC displayed growth inhibition as determined by MTT assay, and reduced alpha-SMA expression, a marker of cell activation. Inhibition of Jak/STAT and MAPK signaling was confirmed via immunoblot. These data compliment our published results indicating that Hsp90 inhibitors modulate survival pathways and PDAC growth in vitro and in vivo. This has led to an investigator-initiated Phase Ib/II clinical trial of XL888 (Hsp90i) and pembrolizumab (anti-PD-1) now accruing at our institution. Extensive laboratory correlative studies are ongoing to examine the impact of Hsp90 inhibition on anti-PD-1 mediated T cell proliferation, cytokine production, and impact on PSC-derived cytokine signatures. This work is being performed in paired biopsy samples (pre- and on-treatment), and peripheral blood from expansion cohorts of patients with metastatic pancreatic cancer (n=16) or colorectal cancer (n=16).

Resection of pancreatic cancer following induction chemotherapy

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Background: Survival of resectable pancreas cancer (RPC) treated with resection and adjuvant therapy is 22-28 months (mo). Locally advanced unresectable pancreatic cancer (LAPC) treated with combination chemotherapy have a median survival of 24 mo. The objective of this project is to evaluate the effect of neoadjuvant treatment on survival outcome of localized PC. Methods: Charts of localized PC patients treated at Emory University from 2009 to 2016 were reviewed. Information on demographics, stage and treatment was collected. Survival rates were estimated by Kaplan-Meier method and compared with log-rank test. A Cox proportional hazard model was fitted to estimate the adjusted effect of treatment on overall survival(OS). Results: A total of 415 patients were included; 144 RPC, 158 borderline resectable (BRPC) and 108 LAPC. Stage was determined at the multidisciplinary conference. The median age was 67.7 years (30-92); 49% male, and 63% Caucasians. The median OS for RPC, BRPC, and LAPC was 16.9, 14.6 and 10.9 mo, respectively. Stage, type of chemotherapy and age were significant predictors of OS after adjusting for gender, race, age, surgery, stage, chemotherapy, margins and radiation. Of the 144 RPC, 137 underwent surgery and 3 received neoadjuvant treatment; 73 RPC were followed in outside facility with missing follow up data. Of the 71 RPC treated at Emory; 91% received adjuvant gemcitabine. Of the 158 BRPC, 84 underwent surgery; 44 received FOLFIRINOX neoadjuvant therapy, 23 received gemcitabine/nab-paclitaxel, and 16 received gemcitabine single agent. BRPC patients who underwent resection had a median OS of 18.5 mo (95%CI: 14.2, 26.4), significantly longer than RPC (P = 0.044). Combination chemotherapy was significantly associated with improved OS at 36 mo (38.9%) when compared to single agent gemcitabine (6.3% at 36 mo) (p = 0.009). BRPC patients who received FOLFORINOX and surgery had a median OS of 31.5 mo. Conclusions: Overall survival of BRPC patients who undergo resection after FOLFIRINOX is significantly improved (more than doubled) compared to upfront resection for RPC. Preoperative therapy provides the best approach for systemic disease early in the course of treatment.

Phase Ib trial of pembrolizumab and XL888 in patients with advanced gastrointestinal malignancies

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Background: Heat shock protein 90 (HSP90) has a central role in modulating tumor microenvironment, inflammatory signaling pathways (NF-κB, HIF-1α and Jak-STAT), tumor antigen presentation and expression, PD-L1 expression and macrophage migration inhibitory factor (MIF) as well as cytokine production. Inhibitors of HSP90 have been shown in preclinical studies and in patient samples to exert anti-tumor effects and modulate signaling pathways. XL888 is a selective inhibitor of HSP90. Based on this preclinical rationale, we have developed a phase Ib/II trial to determine the recommended phase II dose, evaluate the safety, toxicity profile, preliminary antitumor activity, and immunogenicity of the XL888 and Pembrolizumab combination in previously treated patients with advanced gastrointestinal tumors. Methods: The phase Ib trial design is standard 3+3. XL888 is administered orally (PO) in three dose levels of 45 (DL1), 90 (DL2), 60 (only if DLT on DL2) mg twice weekly with pembrolizumab at 200 mg IV on day 1, in 21-day cycles. Eligible patients must have stage IV or locally advanced unresectable gastrointestinal adenocarcinomas who have failed at least one prior therapy (patients with colorectal adenocarcinoma must have previously received oxaliplatin, irinotecan, and fluoropyrimidine), age ≥18 years, ECOG PS 0-1, no prior anti PD-1 or anti-PD-L1 agent. After recommended phase II dose is established, an expansion phase will enroll 16 patients with pancreatic adenocarcinoma (Arm A) and 16 patients with colorectal adenocarcinoma (Arm B). Primary endpoint response rate. In the expansion phase patients will receive initial cycle (3 weeks) treatment with either pembrolizumab or pembrolizumab plus XL888 and then starting cycle 2 all patients receive the combination. Blood will be collected pre-treatment, post 1st and 2nd cycle. Eight patients in each arm will undergo pre and post treatment tumor biopsies. This design will enable us to evaluate the effects of pembrolizumab alone versus the combination. This study was activated in June 2017 and to date 4 patients were enrolled in dose escalation phase. The dose expansion phase is expected to start accrual in December 2017. Clinical trial information: NCT03095781.

Epidemiology and treatment of high-grade gastrointestinal neuroendocrine tumors (HG-GI-NETs)

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Background: High grade neuroendocrine tumors of the gastrointestinal tract are rare tumors. Management strategies are modeled after small cell lung cancer (SCLC). Treatment patterns and outcomes have not been studied. Methods: Data were obtained from all US hospitals that contributed to the National Cancer Database (NCDB) between 2004 and 2013. Univariate and multivariate testing was done to identify factors associated with patient outcome. Kaplan-Meier analysis and Cox proportional hazards models were used to assess the association between patient characteristics and survival. Results: A total of 1,861 patients were identified for the 10 years of the study. The mean age was 63 years (SD±13), with a male preponderance (53.3%). The vast majority of patients (78.1%) were non-Hispanic Whites. The most common primary sites were pancreas (PNET = 19.4%), large intestine (18.1%), esophagus (17.8%) and rectum (15.5%). About 27.9% of the cases were resectable at the time of diagnosis, and distribution across stages 1-IV was 6.6%, 10.5%, 18% and 64.6% consecutively. Liver was a common site of metastases (50.4%), followed by bone (11.3%) and lungs (10.8%). Only 3.5% of the patients had brain metastases. On univariable analysis, age < 65years (HR 0.72; 0.66-0.8; p < 0.001) and treatment at an academic center (HR 0.88; 0.79-0.99; p < 0.034) were associated with improved survival. Multivariable analysis confirmed prognostic advantage of treatment at an academic center. Patients treated with chemotherapy had a median overall survival (OS) of 11.2 months, compared with 1.7 months for those who did not. The median OS for high grade PNET was 6 months, compared to 9.9 months for other HG-GI-NETs. One year and 5-year survival rates were 27.5% vs. 41% and 4.5% vs. 12.3% respectively. Conclusions: This is the largest series of HG-GI-NET. Almost two-thirds of the cases present with metastatic disease. Pattern of metastasis differs from SCLC. Survival is short. Treatment at high volume academic center, younger age and use of chemotherapy are associated with improved survival.

A Phase 1 study of ARQ 087, an oral pan-FGFR inhibitor in patients with advanced solid tumours

Background:

ARQ 087 is an orally administered pan-FGFR inhibitor with multi-kinase activity. This Phase 1 study evaluated safety, pharmacokinetics, and pharmacodynamics of ARQ 087 and defined the recommended Phase 2 dose (RP2D).

Methods:

Patients with advanced solid tumours received ARQ 087 administered initially at 25 mg every other day and dose-escalated from 25 to 425 mg daily (QD) continuous dosing. FGF19, 21, 23, and serum phosphate were assessed as potential biomarkers of target engagement.

Results:

80 patients were enrolled, 61 in dose-escalation/food-effect cohorts and 19 with pre-defined tumour types in the expansion cohort. The most common ARQ 087-related adverse events were fatigue (49%), nausea (46%), aspartate aminotransferase (AST) increase (30%), and diarrhoea (23%). Four patients (5%) experienced grade 1 treatment-related hyperphosphataemia. Dose-limiting toxicity was reversible grade 3 AST increase. The RP2D was 300 mg QD. Pharmacokinetics were linear and dose-proportional from 25 to 325 mg QD, and were unaffected by food. Statistically significant changes (P-value<0.05) suggest phosphate and FGF19 levels as markers of target engagement. In 18 evaluable patients with FGFR genetic alterations, 3 confirmed partial responses (two intrahepatic cholangiocarcinomas (iCCA) with FGFR2 fusions and one urothelial cancer with FGFR2 and FGF19 amplification) and two durable stable disease at ⩾16 weeks with tumour reduction (FGFR2 fusion-positive iCCA and adrenocortical carcinoma with FGFR1 amplification) were observed.

Conclusions:

ARQ 087 had manageable toxicity at the RP2D of 300 mg QD, showed pharmacodynamics effects, and achieved objective responses, notably in patients with FGFR2 genetic alterations.

A phase Ib/II study of cancer stemness inhibitor napabucasin (BBI-608) in combination with gemcitabine (gem) and nab-paclitaxel (nabPTX) in metastatic pancreatic adenocarcinoma (mPDAC) patients (pts)

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Background: Cancer stem cells are fundamentally important for resistance to therapy, recurrence and metastasis. Napabucasin is a first-in-class cancer stemness inhibitor in development identified by its ability to inhibit STAT3-driven gene transcription and spherogenesis of cancer stem cells (Li et al, PNAS 112(6):1839, 2015). Preclinical studies suggest that napabucasin sensitizes heterogeneous cancer cells to chemotherapy and targeted agents. Methods: A phase Ib/II multi-center study in mPDAC pts was performed to confirm the RP2D, PK profile and evidence of anticancer activity of napabucasin in combination with nabPTX and Gem. Pts received napabucasin 240 mg BID with weekly nabPTX 125 mg/m2 and gem 1000 mg/m2for 3 out of every 4 weeks until disease progression (PD) or other discontinuation criterion. Results: Of 71 intent to treat (ITT) pts enrolled, 49 (69%) were treatment-naïve and 22 (31%) received neoadjuvant treatment. There were no significant PK interactions, dose-limiting or unexpected toxicities. Most common adverse events (AEs) included grade 1 diarrhea/cramping, nausea and fatigue with grade 3 AEs noted in 12 pts: fatigue (8), electrolyte imbalance (2), diarrhea (1), dehydration (1), nausea (1) and weight loss (1). Among pts who received RECIST evaluation (60), disease control (DCR; CR+PR+SD) was observed in 55 (92%), with 1 CR (2%) and 26 PR (43%) (31 - 78% regression). Of 11 pts with non-evaluable disease, treatment stopped due to compliance (4), consent withdrawal (3), clinical PD (1), toxicity (1), insurance (1) and death (1). Among 71 ITT pts, DCR was observed in 55 (77%), with 1 CR (1.4%) and 26 PR (37%). Maturing median progression free survival and overall survival (OS) in ITT pts is >7.1 and >10.4 m, respectively. Conclusions: This study showed that napabucasin can be combined with nabPTX and gem, with encouraging signs of efficacy in mPDAC now being confirmed in a phase 3 study. Clinical trial information: NCT02231723. [Table: see text]