Epigenetic and inflammatory markers in older adults with cancer: A Young International Society of Geriatric Oncology narrative review

The number of adults aged ≥ 65 years with cancer is rapidly increasing. Older adults with cancer are susceptible to treatment-related acute and chronic adverse events, resulting in loss of independence, reduction in physical function, and decreased quality of life. Nevertheless, evidence-based interventions to prevent or treat acute and chronic adverse events in older adults with cancer are limited. Several promising blood-based biomarkers related to inflammation and epigenetic modifications are available to identify older adults with cancer who are at increased risk of accelerated aging and physical, functional, and cognitive impairments caused by the cancer and its treatment. Inflammatory changes and epigenetic modifications can be reversible and targeted by lifestyle changes and interventions. Here we discuss ways in which changes in inflammatory and epigenetic pathways influence the aging process and how these pathways can be targeted by interventions aimed at reducing inflammation and aging-associated biological markers. As the number of older adults with cancer entering survivorship continues to increase, it is becoming progressively more important to understand ways in which the benefit from treatment can be enhanced while reducing the effects of accelerated aging.

Bexmarilimab-induced macrophage activation leads to treatment benefit in solid tumors: The phase I/II first-in-human MATINS trial

Macrophage Clever-1 contributes to impaired antigen presentation and suppression of anti-tumor immunity. This first-in-human trial investigates the safety and tolerability of Clever-1 blockade with bexmarilimab in patients with treatment-refractory solid tumors and assesses preliminary anti-tumor efficacy, pharmacodynamics, and immunologic correlates. Bexmarilimab shows no dose-limiting toxicities in part I (n = 30) and no additional safety signals in part II (n = 108). Disease control (DC) rates of 25%-40% are observed in cutaneous melanoma, gastric, hepatocellular, estrogen receptor-positive breast, and biliary tract cancers. DC associates with improved survival in a landmark analysis and correlates with high pre-treatment intratumoral Clever-1 positivity and increasing on-treatment serum interferon γ (IFNγ) levels. Spatial transcriptomics profiling of DC and non-DC tumors demonstrates bexmarilimab-induced macrophage activation and stimulation of IFNγ and T cell receptor signaling selectively in DC patients. These data suggest that bexmarilimab therapy is well tolerated and show that macrophage targeting can promote immune activation and tumor control in late-stage cancer.

Integrating DNA methylation and gene expression data in a single gene network using the iNETgrate package

Analyzing different omics data types independently is often too restrictive to allow for detection of subtle, but consistent, variations that are coherently supported based upon different assays. Integrating multi-omics data in one model can increase statistical power. However, designing such a model is challenging because different omics are measured at different levels. We developed the iNETgrate package ( https://bioconductor.org/packages/iNETgrate/ ) that efficiently integrates transcriptome and DNA methylation data in a single gene network. Applying iNETgrate on five independent datasets improved prognostication compared to common clinical gold standards and a patient similarity network approach.

Pivoting to telemedicine in a single-day multidisciplinary liver tumor clinic during COVID-19: the Texas Liver Tumor Center experience

Cancer guidelines recommend that all patients with hepatocellular carcinoma (HCC) have an evaluation by a multidisciplinary team to assess liver health, stage the cancer, and discuss treatment and palliative care options. Coronavirus disease 2019 (COVID-19) had a catastrophic impact on patients with cancer resulting in increased disease burden due to late diagnosis and treatment delays. Late diagnosis has highlighted the need for the early intervention of palliative care for patients with HCC. Conversion to telemedicine has been essential to caring for patients with all stages of cancer without added delays. Texas Liver Tumor Center (TLTC) offers patients with liver cancer at any stage a single-day multidisciplinary evaluation with tumor board review facilitating the early integration of treatment and palliative care services. National Comprehensive Cancer Network (NCCN) guidelines support increasing and improving access to palliative care. TLTC allows for the early integration of palliative care within a 1-day clinic model with an incorporated tumor board. This unique model of patient care decreases the burden of separate patient visits, may expedite the time from diagnosis to first treatment, facilitates the early intervention of palliative care specialists, and allows for optimal screening for clinical trials. In this review, we will provide an overview of the current multidisciplinary models of care for HCC and describe the successful pivot of TLTC from a fully in-person single-day multidisciplinary clinic with a multidisciplinary tumor board (MDTB) to a fully virtual experience, thereby maintaining access to this unique clinical model of patient care during the COVID-19 pandemic. The ability to pivot from in-person clinical visits to completely virtual visits increases patient access to care and enables more physicians to participate. Areas for future study include the impact on patient experience, clinical outcomes, and cost-effectiveness of this high-resource model.

"iNETgrate": integrating DNA methylation and gene expression data in a single gene network

Integrating multi-omics data in one model can increase statistical power. However, designing such a model is challenging because different omics are measured at different levels. We developed the iNETgrate package (https://bioconductor.org/packages/iNETgrate/) that efficiently integrates transcriptome and DNA methylation data in a single gene network. Applying iNETgrate on five independent datasets improved prognostication compared to common clinical gold standards and a patient similarity network approach.

Comprehensive molecular profiling in patients with advanced biliary tract cancers (BTC) in a Latinx-rich cohort

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Background: BTC are genetically diverse and heterogeneous. Despite knowledge of molecular subtypes of BTC, the distribution of molecular aberrations in the Latinx population has been understudied. These may have prognostic and/or predictive implications. Therefore, we analyzed our cohort of Latinx-rich patients with advanced BTC. Methods: We analyzed patients with advanced BTC, who were seen at the Mays Cancer Center from Jan 2018-Dec 2021. Tumor samples profiled by Next Generation Sequencing (NGS) were identified retrospectively. Associations between demographics, clinical characteristics, and genetic alterations were identified. Results: 88 patients with locally advanced/metastatic BTC were identified. 50 (56.2%) were Latinx. 42 (47.7%) had intrahepatic CA (IHCA), 14 (15.9%) had extrahepatic CA (EHCA), 16 (18.2%) had Gall Bladder Carcinoma (GBC) and 16 (18.2%) had Ampullary/Periampullary Carcinoma (APC). 49 (56%) had NGS on their tumors out of which 30 (61.2%) were Latinx and 19 (38.8%) were non-Latinx. The most commonly altered genes were TP53 (34.7%), KRAS (24.5%), ARID1A (16.3%), BRCA-2 (12.2%), PDL-1 (12.2%), FGFR (12.2%), MET (10.2%), PTEN (10.2%) and HER-2 (8.2%). 14.3% patients had no identifiable mutations. There was no significant difference observed in the rates of different molecular mutations between Latinx and non-Latinx (p=1) and among different histologies of IHCA, EHCA, GBC and APC (p=1). The Median Overall Survival (OS) for Latinx population was 16.1 months (95% CI 12.3-28.2) which was similar to the median OS for non-Latinx population of 15.5 months (95% CI 11.6-28.6) (p=0.69). The median OS was not different due to the presence or absence of any one mutation (p values ranged from 0.04 to 0.9). Conclusions: BTCs are genetically diverse. Somatic alterations were identified in 85% patients who were tested. Only 56 % had molecular testing, when it should be 100% in advanced BTC, per NCCN guidelines. This may be due to inadequate tissue, lack of funding, use of alternate ctDNA, or the patient may have died before getting to testing/repeat biopsy. The likelihood of having a genetic alteration was similar between Latinx and non-Latinx patients and among different sites of disease. Latinx and Non Latinx with advanced BTC had similar survival rates. Survival rate was not different due to the presence or absence of any one mutation. Future studies should prospectively investigate implementation programs for NGS in tumor and blood in all patients with BTCs.

Promising clinical benefit rates in advanced cancers alongside potential biomarker correlation in a phase I/II trial investigating bexmarilimab, a novel macrophage-guided immunotherapy

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Background: Clever-1 is an immunosuppressive scavenger receptor expressed on tumor associated macrophages. High levels of Clever-1 are associated with poor survival and immunotherapy resistance. Bexmarilimab (FP-1305) is a novel humanized anti-CLEVER-1 IgG4-antibody capable of inducing a phenotypic M2 to M1 immune switch of tumor-associated macrophages. Methods: MATINS (Macrophage Antibody To INhibit immune Suppression) trial is a first-in-human phase I/II study (NCT03733990) to assess safety and preliminary efficacy of Bexmarilimab in patients with refractory advanced solid tumours. Part I has been completed with initial good safety profile of the IMP, preliminary signs of efficiency, and recommended dose of 1mg/kg Q3W for part II (ESMO 2020). In Part II (ESMO 2021), 10 distinct solid tumour types were enrolled to assess preliminary efficacy (overall survival (OS), progression free survival (PFS), and clinical benefit rate (CBR). Clever-1 IHC in pre-treatment biopsies with Ventana platform using a primary antibody 4G9 (Santa Cruz) was scored by % of positive cells compared to the viable tumor cells. Results: At the Jan 2022, a total of 193 patients have been enrolled to the study. In the completed cohorts, 138 patients have received 1-21 doses (median 3) of Bexmarilimab Q3W. Bexmarilimab was well tolerated, and no new safety signals were detected. Part I and Part II fully enrolled 11 cancer cohorts, the median PFS was 2.0 months (95% CI 1.9 – 2.0) and the median OS was 5.2 months (95% CI 4.3 – 6.4). CBR for Part II was 17.3% (19/110) at cycle 4 of treatment (by RECIST v.1.1). Notably, 30-40% CBR at cycle 4 was seen in cutaneous melanoma (30%), gastric cancer (30%), cholangiocarcinoma (30%), hepatocellular cancer (40%), and ER+ breast cancer (40%). Six-month survival rates (landmark analysis) were 70.1% for CBR compared to 34.7% for non-CBR patients, with a similar duration of prior therapy in both groups. Preliminary biomarker analysis (n = 77) demonstrated positive trend (p = 0.038) between CBR and higher intratumoral Clever-1 positivity (median of 15% positivity (range 0-25) in CBR and 3% (range 0-85) in non-CBR patients) Conclusions: Bexmarilimab continues to demonstrate promising anti-tumour activity as a monotherapy in several refractory solid tumours. Furthermore, preliminary biomarker analysis suggests a possibility for patient selection based on tumour Clever-1 expression. Further expansion of the study will investigate optimal dosing and biomarkers of efficacy. Clinical trial information: NCT03733990.

Molecular profile of hepatocellular carcinoma (HCC) in older versus younger adults: Does age matter?

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Background: HCC is increasingly prevalent in older adults with rising incidence and an aging population worldwide. Retrospective studies show older patients with HCC may have an increased survival compared to younger patients. However, data is lacking regarding the genomic and biologic differences, that if identified, would potentially change how we treat this disease in younger vs. older patients. Hence, there is a need to better characterize the molecular landscape of the disease in an age-specific manner. We analyzed the association of age with genomic alterations and therapeutic response to sorafenib in a cohort of advanced HCC that had undergone comprehensive molecular profiling. Methods: 487 HCC samples (excluding variants) were analyzed using Next Generation Sequencing (592 gene panel, NextSeq), Whole Exome and Whole Transcriptome Sequencing (NovaSeq), and IHC at Caris Life Sciences (Phoenix, AZ). PD-L1 positivity was determined by IHC (SP-142 clone, cutoff ≥1, 1%). Tumor mutational burden (TMB) was a measure of total somatic mutations per Mb. Immune cell populations were determined by Microenvironment Cell Population (MCP) counter analysis of RNA expression data. Overall survival (OS) calculated from tissue collection to last contact and time on treatment (TOT) with sorafenib were extracted from insurance claims and calculated using Kaplan-Meier curves. Statistical analysis was done using Chi-square, Fisher Exact and Wilcoxon rank sum tests, with p values adjusted for multiple comparisons and q<0.05. Results: Differences in the molecular landscape of HCC stratified by patient age were assayed using a ternary classification based on 1 standard deviation from the mean age (mean age=65; <53: A1 (n=51), 53-77: A2 (n=361), >77: A3 (n=75)). With age, mutational frequencies in CTNNB1 (A1=13.04%, A2=33.43%, A3=38.24%) and TERT (A1=25%, A2=68.84%, A3=76.92%) increased, while ATM (A1=6.52%, A2=0.93%, A3=1.49%) decreased (p<0.05, q>0.05). There were fold increases in median TMB (A2/A1=1.33, A3/A1=1.33, p<0.01), LAG3 (A2/A1=1.75, A3/A1=1.93 p<0.01), CTLA4 (A2/A1=2.05, A3/A1=2.15, p<0.05) expression; median cell fractions of CD8+ T cells (A2/A1=1.37, A3/A1=1.50, p<0.05) & B cells (A3/A1=3.01 p<0.05) increased while cancer associated fibroblasts (A1/A2=0.62, A1/A3=0.69, p<0.01) decreased with age. PD-L1 was not statistically significant. While there was no change in OS, reduced TOT with sorafenib was observed in patients aged>65 (p=0.013). Conclusions: Increased alterations in oncogenic drivers and estimates of CD8+ T cells and B cells were observed in the elderly population with HCC. The enhanced presence of co-inhibitory molecules suggests potential immune evasion. While we observed reduced TOT with sorafenib, additional studies are needed to elucidate the impact of molecular alterations on outcomes with sorafenib and newer therapies (i.e. immunotherapy) in older adults.

Gastroesophageal adenocarcinoma in older adults: A comprehensive narrative review of management by the Young International Society of Geriatric Oncology

Gastroesophageal adenocarcinoma is a disease of older adults with very poor survival rates. Its incidence has risen dramatically across the world in recent decades. Current treatment approaches for older adults are based largely on extrapolated evidence from clinical trials conducted in younger and fitter participants than those more commonly encountered in clinical practice. Understanding how to apply available evidence to our patients in the clinic setting is essential given the high morbidity of both curative and palliative treatment. This review aims to use available data to inform the management of an older adult with gastroesophageal adenocarcinoma.

Second-line treatment with nivolumab, cabozantinib, regorafenib, or best supportive care in patients with advanced hepatocellular carcinoma: analysis at a Hispanic-majority NCI-designated cancer center

BACKGROUND

In the last four years, six regimens were approved by the Food and Drug Association as second-line therapies for advanced hepatocellular carcinoma (HCC). However, there are significant differences between real-world and clinical trial populations. We analyzed survival and toxicities among second-line therapies for HCC in our population.

METHODS

We performed a retrospective cohort study of patients with advanced HCC who received second-line therapies (tyrosine kinase inhibitor or TKI; immunotherapy or IO) or best supportive care (BSC) at a tertiary-referral cancer center serving the South Texas region. Progression-free survival (PFS) was determined, and adverse events were compared between therapies.

RESULTS

In our cohort, median age was 60 years (n=65), and 49 (75%) were Hispanic. 58 (89%) patients received second-line therapy. Child-Pugh (CP) score of cohort: A, 18%; B, 55%; C, 26%. Median PFS (mPFS) was 3.1 months with TKI (n=6), 3.3 months with IO (n=27), and 1.3 months with BSC (n=25). There was improved survival with IO compared to BSC [hazards ratio (HR) =0.31; 95% confidence interval (CI): 0.15-0.63; P=0.0014]. There was no significant difference comparing IO to TKI (HR =0.94; 95% CI: 0.31-2.86; P=0.92), but a trend to improved PFS with TKI when compared to BSC (HR =0.33; 95% CI: 0.10-1.04; P=0.058). TKI group had significantly more rash (P=0.01) and hand-foot syndrome (P<0.001) compared to IO and BSC.

CONCLUSIONS

Our Hispanic-majority cohort with varying liver dysfunction, including CP-B & C cirrhosis, were more likely to receive IO or BSC. Both second-line treatment groups, IO or TKI, demonstrated increased mPFS compared to BSC and were tolerable compared to BSC, with expected toxicity per class of drug.

Molecular differences between lymph nodes and distant metastases compared with primaries in colorectal cancer patients

Lymph nodes (LNs) and distant metastases can arise from independent subclones of the primary tumor. Herein, we characterized the molecular landscape and the differences between LNs, distant metastases and primary colorectal cancers (CRCs). Samples were analyzed using next generation sequencing (NGS, MiSeq on 47 genes, NextSeq on 592 genes) and immunohistochemistry. Tumor mutational burden (TMB) was calculated based on somatic nonsynonymous missense mutations, and microsatellite instability (MSI) was evaluated by NGS of known MSI loci. In total, 11,871 samples were examined, comprising primaries (N = 5862), distant (N = 5605) and LNs metastases (N = 404). The most frequently mutated genes in LNs were TP53 (72%), APC (61%), KRAS (39%), ARID1A (20%), PIK3CA (12%). LNs showed a higher mean TMB (13 mut/MB) vs distant metastases (9 mut/MB, p < 0.0001). TMB-high (≥17mut/MB) and MSI-H (8.8% and 6.9% vs 3.7%, p < 0.001 and p = 0.017, respectively) classifications were more frequent in primaries and LNs vs distant metastases (9.5% and 8.8% vs 4.2%, p < 0.001 and p = 0.001, respectively). TMB-high is significantly more common in LNs vs distant metastases and primaries (P < 0.0001), regardless MSI-H status. Overall, LNs showed significantly different rates of mutations in APC, KRAS, PI3KCA, KDM6A, and BRIP1 (p < 0.01) vs primaries, while presenting a distinct molecular profile compared to distant metastases. Our cohort of 30 paired samples confirmed the molecular heterogeneity between primaries, LNs, and distant metastases. Our data support the hypothesis that lymphatic and distant metastases harbor different mutational landscape. Our findings are hypothesis generating and need to be examined in prospective studies.

Molecular profile of BRCA-mutated biliary tract cancers

Introduction

Prognosis of biliary tract cancers (BTC) remains dismal and novel treatment strategies are needed to improve survival. BRCA mutations are known to occur in BTC but their frequency and the molecular landscape in which they are observed in distinct sites of BTC remain unknown.

Material and methods

Tumour samples from 1292 patients with BTC, comprising intrahepatic cholangiocarcinoma (IHC, n=746), extrahepatic cholangiocarcinoma (EHC, n=189) and gallbladder cancer (GBC, n=353), were analysed using next-generation sequencing (NGS). Tumour mutational burden (TMB) was calculated based on somatic non-synonymous missense mutations. Determination of tumour mismatch repair (MMR) or microsatellite instability (MSI) status was done by fragment analysis, immunohistochemistry and the evaluation of known microsatellite loci by NGS. Programmed death ligand 1 expression was analysed using immunohistochemistry.

Results

Overall, BRCA mutations were detected in 3.6% (n=46) of samples (BRCA1: 0.6%, BRCA2: 3%) with no significant difference in frequency observed based on tumour site. In GBC and IHC, BRCA2 mutations (4.0% and 2.7%) were more frequent than BRCA1 (0.3% and 0.4%, p<0.05) while in EHC, similar frequency was observed (2.6% for BRCA2 vs 2.1% for BRCA1). BRCA mutations were associated with a higher rate in subjects with MSI-H/deficient mismatch repair (19.5% vs 1.7%, p<0.0001) and tumours with higher TMB, regardless of the MMR or MSI status (p<0.05).

Conclusions

BRCA mutations are found in a subgroup of patients with BTC and are characterised by a distinct molecular profile. These data provide a rationale testing poly(ADP-ribose)polymeraseinhibitors and other targeted therapies in patients with BRCA-mutant BTC.

Double disparities in patients with gastric cancer: Clinicopathology and survival of older adults in a Hispanic-rich population

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Background: Gastric cancer incidence increases with advancing age with a median age at diagnosis of 68. However, older adults (age ≥65) are underrepresented in clinical trials. Additionally, Hispanic populations have a higher incidence of gastric cancer compared with non-Hispanic patients and there is evidence that this population has worse outcomes. Given this double disparity in older Hispanic adults, we evaluated the differences in disease characteristics at diagnosis and survival outcomes in older adults compared to younger adults with gastric cancer at our South Texas cancer center serving a predominantly Hispanic population. Methods: We performed a retrospective analysis of patients with a diagnosis of gastric cancer from 2000 – 2018, who had follow-up at Mays Cancer Center, San Antonio, TX. Older patients were defined as ≥65 years and younger patients were defined as <65 years. Median overall survival (mOS) was estimated from Kaplan-Meier curves and groups were compared using the log-rank test. Results: A total of 190 patients met criteria for analysis. Patients were predominantly younger (age <65), with 128 (67.4%) young and 62 (32.6%) older. Most patients were Hispanic (66.4% of younger and 64.5% of older) and male (51.6% of younger and 66.1% of older). The majority of patients had an ECOG performance status of 0-2, including 61.7% and 64.5% (p = 0.55) of younger and older patients, respectively. At baseline, there was no significant difference in location of primary tumor, grade, stage at diagnosis, or histologic classification between younger and older patients (Table). There was also no significant difference between the two groups in H. pylori status, location of metastases, or HER2 status. Of the 109 patients with follow-up for survival, the mOS was 17 months (95% CI: 15-55) for younger patients versus 14 months (95% CI: 13-NR) for older patients (p = 0.19). Conclusions: In this retrospective analysis of predominantly Hispanic patients with gastric cancer, we found that there were no statistically significant differences in clinicopathologic features at diagnosis or in survival between younger versus older adults. Our study was approximately 2/3 Hispanic, a population for which there is a paucity of data, especially in older adults. Given the limited published research available to guide the management of older patients with gastric cancer, including Hispanics, further prospective real-world studies are needed to evaluate toxicity and quality of life in order to improve the care of older adults with gastric cancer. [Table: see text]

Phase II study of modulation of sorafenib (SOR)-induced autophagy using hydroxychloroquine (HCQ) in advanced hepatocellular cancer (HCC): Planned interim efficacy and safety analysis

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Background: SOR is the first systemic therapy approved for advanced HCC, but has shown only modest improvements in survival. Resistance to SOR in pre-clinical models has been attributed to autophagy induction. Autophagy inhibition with HCQ enhanced SOR-induced cell death and apoptosis in early pre-clinic and clinical studies. Data from the phase I study of SOR plus HCQ in advanced solid tumors at showed clinical safety and efficacy. Therefore, we conducted a prospective study to evaluate efficacy of SOR and HCQ in advanced HCC patients (pts) (NCT03037437) and report planned interim analysis for our first-line cohort. Methods: Prospective phase II study of SOR 400 mg po BID + HCQ 400 mg daily in pts with advanced HCC (CP A-B8 cirrhosis). Cohort 1: first-line SOR/HCQ. Cohort 2: add HCQ upon progressing on SOR. CP B pts started at 200 mg BID, with dose escalation as tolerated. Cycle = 4 weeks. Primary endpoint: mTTP. Secondary endpoints: mOS, response by RECIST; AEs (NCI-CTCAEv3.0); PD analysis for markers of autophagy and immunity. Pts evaluable for efficacy if completed C1. Planned interim efficacy and safety analysis approved by DSMB is reported here. Results: For cohort 1, n = 19. Median age 63.5 (51-80). 80% Male; 65% Hispanics. ECOG 0-1: 100%. CP B cirrhosis: 32%. Etiology of cirrhosis: HCV 84%, ETOH 26%, NASH 5%. BCLC B 21%, C 70%. AFP > 400: 47%, PVT: 32%, metastases: 64%, post-transplant: 21%. Reason off study: PD (n = 10), toxicity (n = 2), lost to f/u (n = 1), withdrew (n = 1). N = 16 completed C1, n = 2 remain on study. mTTP is 4.2 months (95% CI: 3.7-NA). mOS 13.8 months (95% CI: 13.8-NA). Response Rate (CR+PR): 25%. Best response: CR n = 1 (6%), PR n = 3 (19%), SD n = 7 (44%). 4+ cycles: n = 9 (56%). % alive. Median duration of response 7.6 months (3.67-20). Gr 1/2 AEs as expected from SOR. Gr 3: AST elevated (n = 1), diarrhea (n = 1) due to SOR. Gr 2 rash (n = 1) due to HCQ. No Gr 4/5. Dose reduction: 70% for SOR, 0% for HCQ. PD analysis on the 3 responders show favorable immune profile changes (increase in cytotoxic T cells and decrease T Regs). Conclusions: SOR/HCQ had a better response rate (25%) than historically SOR alone (2%) in pts with advanced HCC, predominantly BCLC C, with CP A and B cirrhosis. While immune checkpoint inhibitors (ICIs) are taking the forefront in advanced HCC, SOR/HCQ may have a role in patients with CP B cirrhosis, transplant or contraindications to ICIs. Further, analysis of predictive markers of response is ongoing. Clinical trial information: NCT03037437.

Second-line tyrosine kinase inhibitors (TKIs) versus immunotherapy (IO) for advanced hepatocellular carcinoma (HCC): Real-world efficacy and safety analysis in patients with varying liver dysfunction

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Background: Within the last 4 years, the FDA approved five drugs as second-line therapies for advanced HCC. At our cancer center, the majority of our patients are Hispanic with varying liver dysfunction, and this real world population is not represented in registration trials of TKIs and IOs. Therefore, we analyzed survival and toxicities among second-line therapies for HCC at our Hispanic-majority NCI-designated cancer center. Methods: Retrospective analysis of patients with advanced HCC diagnosed at Mays Cancer Center from 1/2015-3/2019 who received second-line therapies, including IO (i.e. nivolumab), TKIs (i.e. cabozantinib, regorafenib), or hospice/best supportive care (BSC). Progression-free survival (PFS) was determined using Kaplan-Meier method, and hazard ratios estimated with Cox proportional hazards model. AEs according to Common Terminology Criteria for AEs v5.0 were analyzed with Fisher’s exact test. Results: Of the patients receiving first-line therapy, the median age was 60 years (n=65), and patients were 75% (n=49) Hispanics. 58 (89%) patients went onto receive second-line therapy. Child-Pugh (CP) score: A 17%, B 55%, C 28%. Median PFS was 3.1 months with TKI (n=6), 3.3 months with IO (n=27), and 1.3 months with BSC (n=25) (Table). There was improved survival with IO when compared to BSC (HR=3.26; 95% CI: 1.58-6.72; p=0.00136). There was no significant difference when comparing IO to TKI (HR=0.94; 95% CI: 0.31-2.86; p=0.92), but a trend to improved PFS with TKI when compared to BSC (HR=3.08; 95% CI: 0.96-9.84; p=0.06). TKI group had significantly more rash (p=0.01) and hand-foot syndrome (HFS) (p<0.001) compared to IO and BSC. All other AEs demonstrated no significant difference between groups (Table). Conclusions: In our Hispanic-majority cohort, patients with varying liver dysfunction, including CP B & C cirrhosis, were more likely to receive IO or BSC. Both second-line treatment groups (IO or TKI) had increased mPFS compared to BSC. Both IO and TKI groups were tolerable compared to BSC, with expected toxicity per class of drug. More prospective studies comparing second-line agents should be done in patients with varying liver dysfunction to understand survival, tolerability, and quality of life. [Table: see text]

Implementation of Universal Tumor Screening of Colorectal Cancer for Detection of Lynch Syndrome at a Hispanic-Rich County Hospital

INTRODUCTION

In 2014, a reflexive screening protocol for Lynch syndrome (LS) via an immunohistochemistry (IHC) assay was shown to be cost-effective; however, the screening rates at a predominant Hispanic-rich institution are unclear. We hypothesized that implementation of a universal tumor screening (UTS) protocol requiring screening for LS via IHC in patients with newly diagnosed colorectal cancer (CRC) at our Hispanic-rich institution would improve detection of LS by increasing screening rates.

METHODS AND MATERIALS

This is a retrospective analysis of screening rates of 3 sequential cohorts of newly diagnosed patients with CRC between January 2012 and April 2016 at the University Health System and with follow-up at National Cancer Institute-designated Mays Cancer Center at University of Texas Health San Antonio. Cohort 1 consisted of patients screened using old screening guidelines (PRE). Cohort 2 consisted of patients screened when treating clinicians were receiving education on the new protocol (PERI). Cohort 3 consisted of patients screened after implementation of the UTS protocol (POST).

RESULTS

The majority of 312 patients were Hispanic (62.5%), 18.1% were < 50 years, and 81.9% were ≥ 50 years of age (median age, 57 years). Of patients with CRC screened for LS via IHC, the PRE, PERI, and POST cohorts had screening rates of 31%, 64%, and 58%, respectively. We found significant differences when comparing the PRE with POST sequential cohorts (P < .01).

CONCLUSION

The quality of Lynch syndrome-related family histories and screening rates were significantly improved after implementation in our Hispanic-rich population. Future studies are warranted to provide insight into clinical effects of increased screening, provider and patient surveillance, and screening-related systemic barriers.

Real-world use of second-line treatments in patients with advanced hepatocellular carcinoma (HCC) of varying liver dysfunction: Analysis at a Hispanic-majority cancer center

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Background: Hispanics have a higher incidence of HCC but are underrepresented in clinical trials leading to approvals of new therapies for HCC. Further, there is a lack of prospective trials comparing second-line treatments for HCC. Therefore, we reviewed the treatment patterns and tolerability of second-line treatments for HCC at our Hispanic-majority NCI-designated cancer center. Methods: Retrospective analysis of patients with advanced HCC, diagnosed at Mays Cancer Center at UT Health San Antonio from 1/2015-3/2019, who received second-line therapies, including, tyrosine kinase inhibitors (TKIs; Ie, cabozantinib, regorafenib) and immunotherapy (IO; ie, nivolumab), clinical trials, hospice/best supportive care (BSC). Child Pugh cirrhosis and adverse events were be compared. Results: Median age 59 (n = 58), Hispanics n = 43 (74%), Cause of cirrhosis: HCV 42 (74%), HBV 1, EtOH 33, NAFLD/NASH 13. BMI overweight/obese 33 (57%). Child-Pugh: A 9 (16%), B 30 (52%), C 16 (28%) (Table). BCLC B 6 (10%), C 47 (81%). CLIP: 1-2 (16%), 3 (38%), 4+ (41%). Second-line treatments: TKI (4, 7%), IO (24, 41%), Clinical trials (3, 5%), BSC (24, 41%). Toxicities (Table). Dose interruptions or reductions: All 18 (31%), TKIs 3 (75%), IOs (58%), trials (33%). Conclusions: In our Hispanic-majority cohort, 41% of patients with HCC were not candidates for second-line treatments (BSC). Of those who received second-line treatments, most received IOs, including patients with Child-Pugh B and C cirrhosis, with 58% requiring dose interruptions. Only 5% enrolled on clinical trials. Real-world patients are significantly different than clinical trial populations, and we need more prospective real-world analyses of these treatments to better understand efficacy, tolerability and quality of life. [Table: see text]

Hepatocellular carcinoma in older adults: A comprehensive review by Young International Society of Geriatric Oncology

Given the prevalence and the rising incidence of hepatocellular carcinoma (HCC) in older adults worldwide, there is an urgent need to improve our understanding of the implications of treatment modalities in this population. The care of older patients with HCC is challenging due to the lack of evidence-based recommendations in this population. The current treatment approach for older patients relies on extrapolation of data from clinical trials conducted mostly in younger patients or fit older adults. Further, in the last few years, the arsenal of systemic treatments has increased with currently seven FDA-approved therapies available for patients with advanced HCC. Therefore, understanding how to apply current data to this unique and diverse patient population is necessary. This review will aim to shed light on the approach to older adults with HCC through an assessment of available data in the literature.

Pembrolizumab in Combination with the Oncolytic Virus Pelareorep and Chemotherapy in Patients with Advanced Pancreatic Adenocarcinoma: A Phase Ib Study

PURPOSE

Pelareorep is an intravenously delivered oncolytic reovirus that can induce a T-cell-inflamed phenotype in pancreatic ductal adenocarcinoma (PDAC). Tumor tissues from patients treated with pelareorep have shown reovirus replication, T-cell infiltration, and upregulation of PD-L1. We hypothesized that pelareorep in combination with pembrolizumab and chemotherapy in patients with PDAC would be safe and effective.

PATIENTS AND METHODS

A phase Ib single-arm study enrolled patients with PDAC who progressed after first-line treatment. Patients received pelareorep, pembrolizumab, and either 5-fluorouracil, gemcitabine, or irinotecan until disease progression or unacceptable toxicity. Study objectives included safety and dose-limiting toxicities, tumor response, evaluation for reovirus replication, and immune analysis in peripheral blood and tumor biopsies.

RESULTS

Eleven patients were enrolled. Disease control was achieved in three of the 10 efficacy-evaluable patients. One patient achieved partial response for 17.4 months. Two additional patients achieved stable disease, lasting 9 and 4 months, respectively. Treatment was well tolerated, with mostly grade 1 or 2 treatment-related adverse events, including flu-like symptoms. Viral replication was observed in on-treatment tumor biopsies. T-cell receptor sequencing from peripheral blood revealed the creation of new T-cell clones during treatment. High peripheral clonality and changes in the expression of immune genes were observed in patients with clinical benefit.

CONCLUSIONS

Pelareorep and pembrolizumab added to chemotherapy did not add significant toxicity and showed encouraging efficacy. Further evaluation of pelareorep and anti-PD-1 therapy is ongoing in follow-up studies. This research highlights the potential utility of several pretreatment and on-treatment biomarkers for pelareorep therapy warranting further investigation.

Implementation of a geriatric oncology screening tool (G8) in an academic oncology practice serving a Hispanic-rich population

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Background: ASCO recommends utilization of the G8 screening tool to assist in predicting mortality, but there are limited data in Hispanic patients. Our practice utilizes the G8 to identify patients who may need additional support and/or treatment modifications to decrease risk of mortality. Therefore, we built the G8 in our Electronic Medical Record (EMR) with reflex to geriatric consultation in our Hispanic-rich patient population. Methods: This is an implementation study with a team-based approach to improve the utilization and increase geriatric oncology assessments in our practice. The G8 is a geriatric screening tool of eight questions (completion time: 3 to 5 minutes). If the score is </=14, a reflexive geriatric consultation box appears on the screen to recommend a referral to Geriatrics for a Comprehensive Geriatric Assessment (CGA). Nurses were empowered to complete the G8 on all new cancer patients 65+ years. Results: 215 patients had a G8 recorded in the EMR between August 2018 - March 2019. Providers completing: 10 (5%) MD/APP, 205 (95%) RNs. 119 patients were non-Hispanic, 96 were Hispanic. Of Hispanic patients, 74 (77%) spoke English, 5 (5%) spoke English and Spanish, 16 (17%) spoke Spanish, 1 (1%) spoke other. 205 patients (95.3%) were 65+ years. Average G8 score for all patients 65+ was 11.1. Of patients 65+, 169 patients (82%), scored </=14, indicating higher mortality risk. Conclusions: Integration of the G8 into our practice has been slow and steady. We believe this is partly due to lack of awareness of the benefit of the G8. Empowering nurses to complete the G8 has improved screening at our cancer center. To further improve awareness and utilization, we have initiated an interprofessional education lecture series regarding care of geriatric oncology patients, which provides nurses CNE. As we gather data on the reflex referrals to geriatricians for CGA, we will work on goals to increase MD/APP engagement.

[Table: see text]

Abstract 2272: Exploratory analysis of T cell repertoire dynamics upon systemic treatment with the oncolytic virus pelareorep in combination with pembrolizumab and chemotherapy in patients with advanced pancreatic adenocarcinoma

Background: Pelareorep is an immuno-oncolytic virus that induces an inflamed tumor phenotype in metastatic adenocarcinoma of the pancreas (MAP). Systemically delivered pelareorep in combination with chemotherapy achieves 1 & 2 year-survival rates of 46% & 24% in MAP pts, respectively. Analysis of tumor tissue from patients (pts) treated with pelareorep, chemotherapy and anti-PD-L1 have shown reovirus RNA and protein replication, T-cell infiltration, and upregulation of PD-L1, highlighting that effective T-cell recognition of tumor antigens may be critical to success for this combination therapy. Thus, we hypothesized that pelareorep in combination with chemo and pembrolizumab in pts with MAP would alter the peripheral T-cell repertoire, creating new T-cell clones via the release of novel neoantigens in addition to expanding existing T-cell clones.

Methods: A phase 1b study enrolled 11 MAP pts who progressed after first-line treatment. Pts received pelareorep (4.5e10 TCID 50 IV, D1 & D2), plus pembrolizumab (2mg/kg IV, D8) plus either 1) 5-FU (LV (200 mg/m2 /5-FU 200 mg /m2 IV bolus, 5-FU 1200mg/m2 continuous IV infusion D1) or 2) gemcitabine (1000 mg/m2 IV, D1), or 3) irinotecan (125 mg/m2 IV, D1) q3w, until disease progression/unacceptable toxicity. DNA from peripheral blood mononuclear cells from nine patients at cycle 1 day 1 (C1D1) & C2D1 (approx. 3 weeks later) was analyzed using the immunoSEQ® Assay (Adaptive Biotechnologies, Seattle) sequencing the T-cell receptor beta chain region to interrogate changes in the T-cell repertoire.

Results: The median Morisita index between C2D1 and C1D1 was 0.83 with 3 samples below 0.6, indicative of significant peripheral repertoire turnover. The median number of expanded clones equated to 45.7 per 100,000 cumulative templates; normal variation over 4 weeks is ~ 5-10 expanded clones. Strikingly, most (median: 86%) peripheral clonal expansion occurred in clones below the limit of detection at C1D1. Cox regression analysis revealed that high peripheral clonality correlates with progression free survival at C1D1 (p=0.01, HR=0.053). Moreover, high clonality correlates with overall survival at both C1D1 (p=0.013, HR=0.124) and C2D1 (p=0.010, HR=0.079).

Conclusions: High levels of peripheral T-cell repertoire turnover occur between C1D1 and C2D1. Repertoire turnover is accompanied by significant clonal expansion, mostly by expansion of new clones (i.e. undetected in C1D1). Higher peripheral clonality is associated with better progression free survival at C1D1, and overall survival at C1D1 and C2D1. This research highlights the potential utility of T-cell clonality as a predictive and prognostic biomarker to pelareorep therapy and warrants further clinical investigation.

Citation Format: Grey A. Wilkinson, Devalingam Mahalingam, Sukeshi Patel Arora, Paul A. Fields, Patrick Raber, Karol Cheetham, Matt Coffey. Exploratory analysis of T cell repertoire dynamics upon systemic treatment with the oncolytic virus pelareorep in combination with pembrolizumab and chemotherapy in patients with advanced pancreatic adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2272.

Frequency of BRCA mutation in biliary tract cancer and its correlation with tumor mutational burden (TMB) and microsatellite instability (MSI)

4085

Background: Biliary tract cancers constitute ~3% of cancers worldwide with incidence increasing, especially for intrahepatic cholangiocarcinoma (IHC). The prognosis of these tumors remains dismal and novel treatment strategies are needed to improve overall survival. BRCA mutations occur in biliary tract cancers but their frequency in distinct sites of biliary tract cancer is unknown. Moreover, no data are available correlating BRCA mutation with immunogenic markers such as TMB, MSI, or PD-L1 expression. Methods: Tumor samples from 1288 primary biliary tract cancers, comprising IHC (n = 746), extrahepatic cholangiocarcinoma (EHC) (n = 189), gallbladder (GBC) (n=353) were profiled at Caris Life Sciences, Phoenix, AZ. Testing included NextGen SEQ (MiSeq on 47 genes, NextSeq on 592 genes) and PD-L1 IHC (SP142). TMB was calculated based on somatic nonsynonymous missense mutations, and MSI was evaluated by NGS of known MSI loci. Results: BRCA mutations were detected in 3.6% (N = 46) of samples ( BRCA1 0.6%, BRCA2 3%), no differences were seen based on the site of the tumor. In GBC and IHC BRCA2 mutations (4.0% and 2.7%) were more frequent than BRCA1 (0.3% and 0.4, p < 0.05) while in EHC, similar frequency was observed ( BRCA1: 2.1%; BRCA2: 2.6%). There was no significant association with gender or age. In BRCA-mutant biliary tract cancer the most frequently mutated genes were TP53 (55.6%), ARID1A (52.2%) and KRAS (26.1%), KMT2D/C (20%, 13%) and CDKN2A(13%). Overall, BRCA mutations were associated with a higher rate of MSI-H (19.5% vs 1.7%, p = 0.001) and higher TMB in both MSI-H and MSS tumors (p<0.05). When investigated separately, BRCA association with elevated TMB was seen in IHC and EHC, but not in GBC. No correlation was seen with PD-L1 expression. TP53, KMT2D/C, RB1, PTEN, KDM6A mutations and FGFR1 amplifications were significantly higher in BRCA mutated tumors (p < 0.05). Conclusions: BRCA mutations are found in a significant subgroup of biliary tract tumors and are associated with an immunogenic tumor profile. These data provide rationale for trials testing PARP inhibitors in combination with immunotherapy and targeted therapies in patients with BRCA-mutant biliary tract cancers that are MSS.

Prediction of response to pelareorep plus pembrolizumab in pancreatic ductal adenocarcinoma (PDAC)

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Background: Pelareorep is an oncolytic reovirus that can induce an inflamed T-cell-infiltrated (hot) phenotype in PDAC. In a phase Ib trial, pelareorep was administered in combination with pembrolizumab and chemotherapy in patients (pts) with advanced, pre-treated PDAC. The safety profile was acceptable and efficacy results were encouraging (Mahalingam ASCO GI 2018). Here we present the results of immune analysis in peripheral blood. Methods: Peripheral blood mononuclear cells (PBMCs) were collected on cycle 1 day 1 (C1D1, pre-pelareorep), C1D8 (pre-pembrolizumab) and C2D1 (pre-pelareorep). RNA from PBMCs was analyzed using a customized Nanostring panel. The research-use only immunoSEQ Assay (Adaptive Biotechnologies, Seattle, WA) was used to characterize T-cell receptors from PBMCs. Results: Eleven pts were enrolled. Disease control was achieved in 50% of the 6 efficacy-evaluable pts. One pt achieved PR that lasted 17.4m. Two additional pts achieved SD, lasting 277 and 126 days. Downregulation (relative change < -1.5) of CD1b (C1D1), HLA-C, MAPK14 (C1D8), CD63, LY96, LTF, TXK, TNFSF13, IL25, C1QB (C2D1) and upregulation ( > 1.5) of IL17F (C1D1), MAGEA4, CCL7 (C1D8), CSF1, ICOS, LILRA4, TICAM2 (C2D1) was observed in pts with clinical benefit vs. no clinical benefit (raw p < 0.05). Increase in clonal diversity was noted during therapy overall (Table). C2D1 had significantly more clonal expansion than C1D8; ~30% of expanded clones from C1D8 were also expanded at C2D1 (durable). High numbers of early expanded (C1D8 only) and durable clones were associated with longer survival. Conclusions: Pts with disease control had higher baseline IL17F compared to non-responders. On-treatment relative decrease in IL25 (Th2), increase in LILRA4, TICAM2 (antiviral response) and ICOS were noted in these pts. There was new clone expansion after treatment overall; ~30% of expanded clones at C1D8 were durable. Early and durable clonal expansion correlated with survival. A phase II trial with pelareorep plus pembrolizumab in advanced PDAC is ongoing. Clinical trial information: NCT02620423. [Table: see text]

Modulation of autophagy: A phase II study of vorinostat (VOR) plus hydroxychloroquine (HCQ) vs regorafenib (RGF) in chemo-refractory metastatic colorectal cancer (mCRC)

3551

Background: Agents targeting the angiogenic pathway have been a cornerstone therapy in mCRC. In chemo-refractory mCRC, RGF, an oral multikinase inhibitor with considerable angiogenic inhibition, has shown modest effects on survival. We reported that autophagy modulation using the autophagy inhibitor, HCQ, enhances the anti-cancer activity of the histone deacetylase inhibitor, VOR, via ubiquitinated protein accumulation in CRC. A phase 1b study confirmed VOR/HCQ is active and tolerated in refractory mCRC. We conducted a prospective randomized study to evaluate efficacy of VOR/HCQ vs RGF in mCRC patients (NCT02316340) and report a planned interim analysis. Methods: Randomized, controlled trial of VOR 400 mg and HCQ 600 mg PO daily vs RGF 160 mg PO daily (3 weeks on, 1 week off), Q4weeks, in advanced CRC patients. Crossover was optional after first progression. A total of 76 patients are planned. Primary endpoint: mPFS. Secondary endpoints: mOS; adverse events (NCI-CTCAEv3.0); PD analysis: 27-plex Human Cytokine Array, NGS analysis (Guardant Health) on cell-free, ctDNA. Results: At interim analysis, n = 42 patients enrolled from 2/2015-10/2017: n = 20 VOR/HCQ (5 crossed to RGF), n = 22 RGF (13 crossed to VOR/HCQ). 38 patients evaluable (at least C1 completed). Median age 58.4, 40% NH vs 60% H. mPFS on first arm: 1.90 mo VOR/HCQ vs 4.35 mo RGF [p = 0.032, HR: 2.277]. mOS: 6.77 mo VOR/HCQ vs 7.23 mo RGF [p = 0.90, HR: 1.05]. Grade 3/4 AEs (see table). In both arms, there was trend towards decreased IL-1b, IL-2, IL-6, IL-10, TNFα, IFNγ but an increase in GM-CSF after treatment. Responders (4+ cycles) had lower baseline MaxMAF versus nonresponders for both arms. In responders, there was trend toward a decrease in MaxMAF at C2 and then increase at progression. Conclusions: VOR/HCQ did not improve survival when compared to RGF. VOR/HCQ has a favorable safety profile, but further planned subgroup analysis is pending to identify biomarkers of efficacy in responders. Clinical trial information: NCT02316340. [Table: see text]

Molecular differences between lymph nodes (LNs) and distant metastases (mets) in colorectal cancer (CRC)

3130

Background: LNs mets are thought to occur before distant mets. However, lymphatic and distant mets arise from independent subclones of the primary tumor, suggesting that LNs are not essential intermediaries for distant mets. We aimed to comprehensively characterize the molecular profile of LN mets and to explore the differences between LN vs distant mets and primary tumors. Methods: Tumor samples from primary CRCs, LNs, and distant mets were analyzed using NGS (MiSeq on 47 genes, NextSeq on 592 genes), immunohistochemistry. Tumor mutational burden (TMB) was calculated based on somatic nonsynonymous missense mutations, and microsatellite instability (MSI) was evaluated by NGS of known MSI loci. Results: In total, 11871 tumors samples were examined, comprising primaries (N = 5862), distant (N = 5605) and LNs mets (N = 404). The most frequently mutated genes in LNs were TP53 (72%), APC (61%), KRAS (39%), ARID1A (20%), and PIK3CA (12%). LNs showed a higher mean TMB (13 mut/MB) vs distant mets (9, P < .0001). TMB-high (17mut/MB) was more frequent in primaries and LNs vs distant mets (9.5% and 8.8% vs 4.2%, P < .001 and P = .001, respectively), as well as MSI-H (8.8% and 6.9% vs 3.7%, P < .001 and P = .017, respectively). TMB-high is significantly higher in LNs vs distant mets and primaries (P < .0001), independent of MSI-H status. Analyzing distant mets by location, LNs showed higher TMB compared to lung, liver and peritoneum mets (P < .0001). Overall, LNs showed significantly different rates of mutations in APC, KRAS, PI3KCA, KDM6A, and BRIP1 (P < .01 for all comparisons) vs primaries; while presenting a distinct molecular profile compared to distant mets ( TP53 72 vs 67%; KRAS 39 vs 50%; RNF43 7 vs 4%; ATM 5 vs 3%; KDM6A 4 vs 1%; BRCA2 4 vs 2%; MSH6 3 vs 2%; PTCH1 4 vs 1%; BRCA1 2 vs 1%; GNAS 2 vs 5%; P < .05 for all comparisons). Our cohort of 30 paired samples confirmed the molecular heterogeneity between primaries, LNs, and distant mets. Conclusions: This is the largest study to investigate the molecular differences between LNs mets, distant mets and primary tumors in CRC patients. Our data support the hypothesis that lymphatic and distants mets harbor different mutation profiles which suggests that they may arise from distinct subclones.

Combination chemotherapy for pancreatic cancer in older adults: Efficacy and safety analysis of patients at a majority-Hispanic NCI-designated cancer center

389

Background: Pancreatic cancer (PCa) is more frequent in older adults, but older patients are underrepresented in large clinical trials. There is limited data on efficacy and safety of regimens such as FOLFIRINOX or nab-paclitaxel/gemcitabine (nab-gem) in older adults, especially Hispanics. Therefore, we compared the efficacy and safety of first-line PCa regimens in older adults. Methods: Retrospective analysis of stage IV PCa at our Hispanic-majority NCI-designated cancer center from 2000-2017. mPFS and mOS estimated from KM curves and groups were statistically compared with the log-rank test. The magnitude of association between dichotomous factors and survival was estimated with the hazard ratio (HR). Results: Forty-eight pts, mean age 71.7 years, median 69.2 (range 65-90). 31% Hispanic; 50% Male. First-line treatment: FOLFIRINOX (n=9), nab-gem (n=11), gem (n=11), other (n=9), supportive care (n=2). Baseline ECOG 0-1: 100%, 94%, 45%, 100%, 1% (p=0.004). Baseline albumin: 3.4, 3.4, 3.1, 3.5, 2.25 (p=0.06). mOS 7.1 months (95% CI 5.9-10.1). mPFS 5.6 months (95% CI: 5.3-NR). mOS by group: 8.6 mo, 7.1 mo, 3.2 mo, 2.9 mo, not available (p=0.95). Most patients had grade 0-2 toxicities (See table). Grade 3-4: fatigue n=2, neutropenia n=1, neuropathy n=1, mucositis n=1. Conclusions: Combination systemic chemotherapy are tolerated in older adults with PCa; however, in our cohort, survival was lower than historic phase 3 clinical trials with these regimens. Patients receive 2+ drugs had higher ECOG and albumin at baseline. Prospective studies with geriatric assessments are needed to determine patients who benefit from combination chemotherapy. [Table: see text]

Systemic Treatment of Advanced Hepatocellular Carcinoma in Older Adults

Over the past 30 years, the incidence in of hepatocellular carcinoma (HCC) in the United States has tripled, largely due to untreated chronic Hepatitis C virus, alcoholic hepatitis, and non-alcoholic steatohepatitis (NASH). Additionally, the incidence of HCC among South Texas Hispanics is higher than elsewhere in the United States. The median age of HCC is 62 years in United States and 67 years in South Texas, with over 30% being 70 years of age or older. However, there is limited data on how to treat older adults with advanced HCC. In this review, we will discuss treatment options for older adults with advanced HCC, further emphasizing the need for prospective studies in this population.

A Phase II Study of Pelareorep (REOLYSIN®) in Combination with Gemcitabine for Patients with Advanced Pancreatic Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis, with 1 and 5-year survival rates of ~18% and 7% respectively. FOLFIRINOX or gemcitabine in combination with nab-paclitaxel are standard treatment options for metastatic disease. However, both regimens are more toxic than gemcitabine alone. Pelareorep (REOLYSIN®), a proprietary isolate of reovirus Type 3 Dearing, has shown antitumor activity in clinical and preclinical models. In addition to direct cytotoxic effects, pelareorep can trigger antitumor immune responses. Due to the high frequency of RAS mutations in PDAC, we hypothesized that pelareorep would promote selective reovirus replication in pancreatic tumors and enhance the anticancer activity of gemcitabine. Chemotherapy-naïve patients with advanced PDAC were eligible for the study. The primary objective was Clinical Benefit Rate (complete response (CR) + partial response (PR) + stable disease (SD) ≥ 12 weeks) and secondary objectives include overall survival (OS), toxicity, and pharmacodynamics (PD) analysis. The study enrolled 34 patients; results included one partial response, 23 stable disease, and 5 progressive disease. The median OS was 10.2 months, with a 1- and 2-year survival rate of 45% and 24%, respectively. The treatment was well tolerated with manageable nonhematological toxicities. PD analysis revealed reovirus replication within pancreatic tumor and associated apoptosis. Upregulation of immune checkpoint marker PD-L1 suggests future consideration of combining oncolytic virus therapy with anti-PD-L1 inhibitors. We conclude that pelareorep complements single agent gemcitabine in PDAC.

Immunotherapy in colorectal cancer: for the select few or all?

Over the past few years, the role of immunotherapy in colorectal cancer (CRC) has expanded, specifically in subsets of CRC with microsatellite instability (MSI) for which newer agents, such as programmed death-1 (PD-1) inhibitors, are efficacious. While other immunotherapeutic agents are more immature in development, they have the potential to enhance the efficacy of PD-1 inhibitors and play a role in the treatment algorithm for all subsets of CRC patients. In this review, we will discuss immunotherapeutic agents in development in patients with CRC. We will review the later phase studies that elucidate the role of immunotherapy in CRC and provide hope for changing the treatment paradigm for CRC in the future.

A study of pelareorep in combination with pembrolizumab and chemotherapy in patients (pts) with relapsed metastatic adenocarcinoma of the pancreas (MAP)

283

Background: Pelareorep (REOLYSIN) is a immuno-oncolytic virus (IOV) that induces an inflamed tumor phenotype secondary to viral infection of cancer cells. In combination with chemotherapy, it achieves 1 & 2 year-survival rates of 46% & 24% in MAP pts, respectively. Tumor analysis from pts showed reovirus protein replication, T-cell infiltration and upregulation of PD-L1. Similarly, the combination of pelareorep with anti-PD-1 antibody documented survival benefit in a pre-clinical model. We hypothesized that pelareorep in combination with chemo and pembrolizumab in pts with MAP would be clinically efficacious. Methods: A phase 1b study enrolled MAP pts who progressed after first line treatment. Pts received pelareorep (4.5 x 10 10TCID 50 IV, D1 & D2), plus pembrolizumab (2mg/kg IV, D8) plus either 1)5-FU (LV (200 mg/m2 /5-FU 200 mg /m2 IV bolus, 5-FU 1200mg/m2 continuous IV infusion D1) or 2) gemcitabine (1000 mg/m2 IV, D1), or 3) irinotecan (125 mg/m2 IV, D1) q3w, until disease progression/unacceptable toxicity. The primary endpoint was safety. Secondary objectives included tumor response & evaluation for reovirus replication/immune analysis. Results: 11 pts were enrolled with pelareorep, pembrolizumab and gem (n = 6), 5-FU (n = 3), or iri (n = 2). Most common grade 1 or 2 TEAEs include: fever (73%), headache (55%), chills (46%), dehydration (36%), fatigue (27%) and anemia (27%). One pt (gem arm), transient Gr 2 increased transaminases was reported on two occasions. Grade 3 or 4 TEAEs occurred in 8 pts (73%): abdominal pain, anemia, arthralgias, biliary obstruction, chills, DVT, diarrhea, fever, hyperglycemia, leukopenia, myalgias, nausea, neutropenia, pulmonary emboli, urinary tract infection and vomiting. Of the 5 efficacy evaluable pts, one had PR (13.8 m duration) and 2 SD (lasting 126 and 277 days). Eight died secondary to PD. On-treatment biopsy show reovirus infection in cancer cells and immune infiltrates. Conclusions: The combination therapy showed manageable safety profiles and antitumor activity in previously treated MAP pts. Further evaluation of anti-tumor activity of pelareorep and anti-PD-1 antibody ± chemotherapy combos is planned. Clinical trial information: NCT02620423.

Phase I clinical trials in refractory colorectal cancer (CRC): Do older adult patients benefit?

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Background: Current clinical trial data are largely driven by younger participants, yet half the population diagnosed with CRC are 70+. Upon progression, many CRC patients (pts) with refractory cancer are referred to phase 1 clinical trials; however, tolerability and clinical benefit is unclear in the elderly. Given our robust phase 1 program, we assessed the efficacy and safety of early therapeutics in the elderly CRC pts. Methods: A historical cohort analysis included mCRC pts enrolled amongst 44 phase I trials from 3/2004 - 9/2012. Median Progression free survival (mPFS) and overall survival (mOS) were estimated from Kaplan-Meier curves and groups were statistically compared with the log rank test. The magnitude of association between dichotomous factors and survival was estimated with the hazard ratio (HR). Results: 139 pts, median age 59 (33-81), 70+ 16.5% (n = 23); KRAS mut 39.4 %. ≥3 prior lines of therapy 73.9 %; Prior EGFR-I 75.5% (100% of KRAS wt). Location: Right 20.9 %, Left 61.9 %, Transverse 4.3 %, Unknown 12.9 %. Phase I agents: VEGF I 19.4%, EGFR/Growth Factor I 9.3%. mOS for < 70 (n = 108) vs 70+ (n = 22): 6.5 vs 4.2 months (HR 1.88, p 0.007). mPFS for < 70 (n = 116) vs 70+ (n = 23): 2.0 months vs x 1.5 months (HR 1.73, P 0.03). There was not a statistical difference between < 70 versus 70+ in regards to dose cohort, number of cycles completed, or adverse events. Survival analysis in terms of risk factors in pts 70+ are in the Table below. Conclusions: Elderly CRC pts are underrepresented (16.5%) in phase 1 clinical trials and have worse survivals than non-elderly pts. Elderly CRC pts with liver and hematologic toxicities had a trend toward worse PFS but no OS. Phase I studies should incorporate prospective assessments to identify risk factors of morbidity and mortality in elderly CRC pts. [Table: see text]

Comparative efficacy and safety of sorafenib in elderly versus non-elderly patients with advanced hepatocellular carcinoma (HCC) with varying liver dysfunction

430

Background: Sorafenib is the only FDA-approved systemic therapy for advanced HCC. The incidence of HCC increases with age, peaking above 70 years; however, we have limited efficacy and safety data in the elderly. Given the prevalence of HCC in South Texas, we assessed the efficacy and safety of sorafenib in the elderly. Methods: Retrospective analysis of HCC patients (pts) receiving sorafenib from 2008-2013. PFS and OS were estimated from Kaplan-Meier curves and groups were statistically compared with the log rank test. The magnitude of association between dichotomous factors and survival was estimated with the hazard ratio (HR). Adverse events (AEs) were graded according to the Common Terminology Criteria for Adverse Events version 4.0. Differences between age groups (65+, < 65) for dose reduction (yes, no), and AEs were analyzed using Fisher’s Exact Test. Results: A total of 118 pts were included. Median age 57 (range 41-93; 65+ 26%). males 81%. Hispanic 73%, Non-Hispanic White 24%. ECOG PS 0–1 93 %. Causes of cirrhosis: Hepatitis C 66%, Hepatitis B 4%, EtOH 58%. Portal vein thrombosis 36%, Extrahepatic disease 38%. Child-Pugh score: A 56%, B 44%. BCLC class: B 13%, C 87%. Among 113 pts 34% were started at 400 mg daily versus 66% started at 800 mg daily. mOS was 11.2 months (mo) (95% CI: 7.8-14.0), mPFS 5.2 mo (95% Cl: 3.9-7.1). In subgroup analysis, mOS for < 65 was 10.2 mo vs 13.5 mo for 65+ (HR 0.67, 95% CI: 0.39-1.16, p = 0.15). mPFS for < 65 was 4.6 mo vs 6.2 mo for 65+ (HR 0.92, 95% CI: 0.58-1.45, p = 0.71). Among 109 pts, dose reductions in < 65 vs 65+ were 64.6 vs 70% (P = 0.66); survival differences were not statistically significant. Among 75 pts there was a trend to improved survival in 65+ patients with AST/Platelet Ratio (APRI) < / = 1.68, but not statistically significant. Sorafenib was tolerated in the elderly. In regards to nausea, fatigue, diarrhea and hand foot syndrome, difference in toxicity was not statistically significant in < 65 versus 65+. Conclusions: In advanced HCC, elderly pts should be offered sorafenib, as it has efficacy and is tolerated in the elderly. Further prospective studies in the elderly are warranted, with evaluation of APRI as a prognostic marker.

Cost and morbidity of surgical management of resectable gallbladder cancer (GBC): Results from the National Inpatient Sample database

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Background: GBC is the most common biliary tract cancer. Based on a retrospective, single-institution data, extended cholecystectomy (EXT) has been recommended over simple cholecystectomy (CHOL) in tumors T2 and above. Retrospective data indicate increased morbidity/mortality with removal of more than 3 segments of the liver compared to CHOL and the effect on long-term survival is unclear. Therefore, we sought to identify short-term outcomes of hospitalization, such as cost and morbidity, for surgical treatment of GBC. Methods: The National Inpatient Sample/Healthcare Cost and Utilization Project (NIS/HCUP) for years 2010, 2011, 2012 and 2013 was surveyed for GBC hospitalizations. Hospitalizations for non-surgical management of GBC were excluded. Results: We identified 5,612 cases; mean age in EXT was 66.8 years vs. 72.4 in CHOL (p<0.001). Patients insured through Medicare were less likely to have EXT (OR: 1.5, 95% CI 1.125-2.064; p=0.007). No difference based on race (OR: 1.14, 95% CI 0.854-1.519; p=0.38). Surgical/Medical morbidity is presented in Table 1. In-hospital mortality was 3.3 vs. 4.1% for EXT and CHOL, respectively (p=0.55). Mean length of stay was higher in the EXT group (9.8 vs. 8.3 days, p=0.03), cost ($32,782 vs. 22,667.3, p=0.003) and total charges ($111,714.7 vs. 81,432.9, p<0.001). Conclusions: EXT for resectable GBC is associated with higher cost of care, probably related to higher risk for surgical site infection and stump leak. Until more evidence for overall survival benefit from EXT in this rare tumor emerges, referral of patients to high-volume centers with the hepatobiliary surgery expertise is recommended. [Table: see text]

Is more surgery better for patients with gallbladder cancer? A survival analysis of extended versus simple cholecystectomy

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Background: Gallbladder cancer (GBC) is a rare cancer; the minority of patients have resectable tumor at diagnosis. Based on retrospective, single-institution data, extended cholecystectomy (EXT) has been recommended over simple cholecystectomy (CHOL) in >T1 tumors; however, effect of EXT on survival is unclear. Thus, we evaluated the survival of patients with resectable GBC at our institution. Methods: Retrospective analysis from 1/1/2005 to 1/1/2016 for patients with GBC. Patients with advanced or metastatic disease were excluded. The Recurrence-free survival (RFS) and overall survival (OS) were calculated using the Kaplan-Meier method. Results: 68 patients with GBC; 26 (38%) with early disease. Twelve patients had EXT. Patient/tumor characteristics are shown in Table. Median RFS was 22 months (95% CI: 9-not reached) and OS was 25 months (95% CI: 15-not reached) for the entire cohort. Median RFS was increased in CHOL (30 months) relative to EXT (9 months); p=0.73. OS appeared similar between the two groups (25 vs. 23 months for CHOL and EXT group, respectively). Conclusions: EXT appears to improve RFS with no effect on OS in patients with early GBC. Due to the limitations of small sample size and retrospective analysis, multi-institutional collaborations are necessary to better identify optimal management. [Table: see text]

Delays in treatment for colorectal cancer patients in an NCI-designated cancer center serving a Hispanic majority community

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Background: Timeliness of cancer treatment is an important aspect of health care quality. Colorectal cancer (CRC) care requires the coordinated multidisciplinary effort of various aspects of the health care system, which can lead to delays between initial diagnoses to definitive therapy. Little is known about the time from diagnosis to cancer-directed treatment, neither about the factors that cause delays or its effect on patient outcomes. Delays to curative surgery beyond 12 weeks are associated with increased mortality in CRC. Longer time to adjuvant chemotherapy is associated with worse survival among patients with resected CRC. The objective of our study is to identify delays in initiation of CRC treatment and its causative factors. Methods: We retrospectively reviewed the medical records of CRC patients who were either initially diagnosed or had initial surgical resection at University Hospital and had further treatment at Cancer Therapy and Research Center, between 7/1/2010 and 12/22/2014. Data were collected on patient and disease characteristics, treatment timelines and outcomes, till pre-specified data cut-off date of 8/1/16. Results: Of 256 patients treated for CRC, majority were males (59 %), Hispanic (59 % ) and uninsured (34 %). Most had non-metastatic disease (70%). 72 % were still alive at the time of data cut-off. The median time from diagnosis to treatment (TDT) was 21 days, with most of te patients getting first treatment between 0-30 days of diagnosis (60 %). Median time from first treatment to first progression or recurrence was 12 months (range 0.9- 42 mos.). Median overall survival (OS) was 17 months (0.1- 51 months). There were no statistically significant difference between the progression or recurrence free survival and OS in patients with TDT < 30 days, 30-89 days and > 90 days. Compared to non-Hispanics, Hispanic patients were more likely to have a TDT of 31-89 days (31% vs 37%, p = 0.0003) and > / = 90 days (3% vs 7%, p = 0.0001). Conclusions: Hispanic patients were more likely to have a longer time from diagnosis to treatment compared to non-Hispanic patients. The factors for such disparities in health care quality and their effect on survival needs to be explored further.

A study of REOLYSIN in combination with pembrolizumab and chemotherapy in patients (pts) with relapsed metastatic adenocarcinoma of the pancreas (MAP)

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Background: REOLYSIN is an immuno-oncology-reoviral agent that induces an inflamed tumor phenotype secondary to viral infection of cancer cells. In combination with chemotherapy, it achieves 1 & 2 year-survival rates of 46% & 24% in MAP pts, respectively. Tumor analysis from pts showed reovirus protein replication, T-cell infiltration and upregulation of PD-L1. Similarly, the combination of REOLYSIN with anti-PD-1 antibody documented survival benefit in a pre-clinical model. We hypothesized that REOLYSIN in combination with chemo and pembrolizumab in pts with MAP would be clinically efficacious. Methods: A phase 2 study (NCT02620423) enrolled MAP pts who progressed after first line treatment. Pts received REOLYSIN (4.5 x 10 10 TCID 50 IV, D1 & D2), plus pembrolizumab (2mg/kg IV, D8) plus either 1)5-FU (LV (200 mg/m2 /5-FU 200 mg /m2 IV bolus, 5-FU 1200mg/m2 continuous IV infusion D1) or 2) gemcitabine (1000 mg/m2 IV, D1), or 3) irinotecan (125 mg/m2 IV, D1) q3w, until disease progression/unacceptable toxicity. The primary endpoint was safety. Secondary objectives included tumor response & evaluation for reovirus replication/immune analysis. We report results of safety cohort analysis. Results: 11 pts were enrolled with REOLYSIN, pembrolizumab and gem (n = 6), 5-FU (n = 3), or iri (n = 2). Grade 1 or 2 TEAEs occurred in all pts: fever (64%), headache (55%), chills (46%), fatigue (46%), dehydration (27%), and nausea (27%). In one pt (gem arm), transient Gr 2 increased transaminases was reported on two occasions. Grade 3 or 4 TEAEs occurred in 8 pts (73%): abdominal pain, anemia, arthralgias, biliary obstruction, chills, DVT, diarrhea, fever, hyperglycemia, leukopenia, myalgias, nausea, neutropenia, pulmonary emboli, vomiting. Of the 5 efficacy evaluable pts, one had PR (6 m duration) and 2 SD (lasting 126 and 221 days). Seven died secondary to PD. On-treatment biopsy show reovirus infection in cancer cells and immune infiltrates. Conclusions: The combination therapy showed manageable safety profiles and antitumor activity in previously treated MAP pts. Further evaluation of anti-tumor activity of REOLYSIN and anti-PD-1 antibody ± chemotherapy combos is planned. Clinical trial information: NCT02620423.

Left Versus Right: Does Location Matter for Refractory Metastatic Colorectal Cancer Patients in Phase 1 Clinical Trials?

PURPOSE

Location of the primary tumor is prognostic and predictive of efficacy with VEGF-inhibitors (I) versus EGFR-I given first-line to metastatic colorectal cancer (mCRC) patients. However, little is known regarding the effect of location on prognosis and prediction in refractory mCRC. We assessed the efficacy of VEGF-I and EGFR-I in regards to location of the primary tumor in patients with refractory mCRC enrolled in early phase studies.

METHODS

A historical cohort analysis of mCRC patients, including 44 phase I trials our institution, from March 2004 to September 2012. Median Progression free survival (mPFS) and overall survival (mOS) were estimated from Kaplan-Meier curves and groups were statistically compared with the log-rank test.

RESULTS

One hundred thirty-nine patients with a median age 59 (33-81). 73.9% received 3+ lines of therapy. All KRAS wild-type patients had received prior EGFR-I.

LOCATION

right 20.9%, left 61.9%, and transverse 4.3%. For survival analysis, transverse CRC were included with right. Of the 112 patients, mOS was left (N = 80) 6.6 months versus right (N = 32) 5.9 months, P = 0.18. mPFS was left (n = 86) 2.0 months versus right (N = 35) 2.0 months, P = 0.76. In subgroup analysis, survival was significant for KRAS wild-type patients with left-sided mCRC had mOS of 6.2 months with other agents versus 9.4 months with EGFR-I (P = 0.03).

CONCLUSIONS

In phase 1 clinical trials, although location alone was not prognostic in heavily pretreated patients, left-sided mCRC had improved survival with EGFR-I. Despite progression on EGFR-I, left-sided KRAS wild mCRC patients should be considered for phase 1 studies of agents targeting growth factor pathways.

Influence of different sources of injected selenium on certain enzymes, glutathione and adenosylmethionine concentration in buffalo (Bubalus bubalis) calves

Sodium selenite and selenomethionine were investigated as possible causative factors for the induction of Degnala disease syndrome in twelve buffalo (Bubalus bubalis) calves divided into three groups of four. Group 1 was the control group and received no additional selenium. Sodium selenite and selenomethionine were given daily as intramuscular injections on a selenium-equivalent basis, with a weekly increment in the dose of 0.05 mg Se/kg live weight from 0.05 to 0.20 mg Se/kg live weight per day, in groups 2 and 3 respectively. Only one animal from group 3 manifested the lesions of Degnala disease. The blood Se concentration and erythrocyte glutathione peroxidase (EC 1.11.1.9; GSH-Px) activity were both greater in groups 2 and 3 than in control group 1. The overall blood Se concentration was 0.22 (SE 0.01), 0.38 (SE 0.12) and 0.77 (SE 0.20) micrograms Se/ml in groups 1 to 3 respectively with corresponding GSH-Px activities of 63.84 (SE 7.38), 88.37 (SE 12.38) and 165.32 (SE 40.62) enzyme units/mg protein. Erythrocyte glutathione reductase (NAD(P)H) (EC 1.6.4.2) activity was not affected by treatment but reduced glutathione content was lower in groups 2 and 3. Liver adenosylmethionine, estimated at autopsy, was lowest (22.87 (SE 6.17) mumol/g) in group 3, and greatest (102.63 (SE 9.39) mumol/g) in group 1 (P less than 0.01). Organic Se sources seemed to accumulate in tissues more than inorganic sources, and might be the causative toxic factors of Degnala disease.