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Gastrointestinal malignancies are challenging cancers with considerable economic and societal impacts on health care systems worldwide. While advances in surgical approaches have provided benefits to a proportion of patients, only modest improvements have been attained in the treatment of patients with advanced disease, resulting in limited improvement in survival rates in these patients. Oncolytic adenoviruses are being developed to address gastrointestinal malignancies. Each platform has evolved to maximize tumor-cell killing potency while minimizing toxicities. Tumor-specific bioengineered adenoviruses using chimeric promoters, prodrug convertase enzymes, lethal genes, tumor suppressor genes, and pseudo-typed capsids can provide the innovations for eventual success of oncolytic virotherapy. This article will review the developments in adenoviral platforms in the context of specific gastrointestinal cancers. From the bench to the implementation of clinical trials, this review aims to highlight advances in the field from its early days to the current state of affairs as it pertains to the application of adenoviral oncolytic therapy to gastrointestinal cancers.

88 Background: BL-8040 is a novel CXCR4 antagonist being developed for multiple oncology indications. Preclinical studies demonstrated that BL-8040 increases the number of immune cells in peripheral blood and promotes CD8+ T cell infiltration into orthotropic pancreatic mouse tumors, reducing tumor load. BL-8040 is being evaluated in a Phase 2a, multicenter, open label trial in patients with metastatic pancreatic cancer (the COMBAT study). Patients are undergoing a 5-day period of monotherapy in which they receive daily doses of BL-8040, followed by 21-day cycles in which patients receive one dose of pembrolizumab and 3 doses/week of BL-8040 until disease progression or discontinuation. To date, 32 patients have been enrolled. Methods: On Day 1 and Day 5, blood samples were taken at pre- and post-dosing, to evaluate peripheral immune cell subset frequency by flow cytometry. In addition, core biopsies were taken from liver metastases, where possible, to assess immune cell infiltration into tumors and the tumor microenvironment (TME). Results: Here we present interim PD biomarker data from the BL-8040 monotherapy portion of the trial. Flow cytometry shows that BL-8040 monotherapy caused an approximately two-fold reduction in frequency of peripheral T regulatory cells, but had no effect on the frequency of T cells, NKT cells or cell populations that contain B cells (CD3- CD56-). Additionally, BL-8040 remained bound to CXCR4 on peripheral immune cells throughout the period of monotherapy. Analysis of available biopsies (N = 7) shows an up to 15-fold increase in the CD3+ population, and up to two-fold increase of CD8+ cells, in the tumor periphery and TME of 43% (3/7) of the patients after five days of BL-8040 monotherapy compared to baseline. Conclusions: In summary, the PD biomarker results in humans support the proposed mechanism of action for BL-8040 that was based on preclinical mouse models. Analysis of tumor biopsies is ongoing, with an emphasis on investigating the effects of BL-8040 on tumor-resident immune cells and the TME. Clinical trial information: NCT02826486.

Purpose FGFR genetic aberrations (GAs) occur in an estimated 10% to 16% of intrahepatic cholangiocarcinomas (CCAs). The natural history of CCA with FGFR GAs, the prognostic role of coexisting GAs, and the outcome with FGFR-targeted inhibitors are unknown. Patients and Methods Patients with CCA with FGFR GAs were identified using next-generation sequencing or fluorescence in situ hybridization from four tertiary cancer centers and compared with FGFR wild-type counterparts. Data reviewed included demographic, treatment, overall survival (OS), and GA data. Fisher’s exact test, Kaplan-Meier plots, and log-rank tests were used for statistical analysis. Results Three hundred seventy-seven patients with CCA were identified, and 95 had FGFR GAs. FGFR2 GA was most common (n = 74, with 63 fusions) and seen in intrahepatic CCA. In patients with CCA, FGFR GAs occurred more frequently in younger patients (≤ 40 years; 20%) compared with older patients (> 40 years; 6.7%; P < .001), presented at an earlier stage (TNM stage I/II v III/IV: 35.8% v 22%, respectively; P = .001), and were associated with a longer OS compared with patients without FGFR GAs (37 v 20 months, respectively; P < .001). This difference remained significant after excluding 36 patients treated with FGFR inhibitors. There was no OS difference ( P = .60) between CCA with FGFR2 fusions (n = 63) versus other FGFR GAs (n = 29). Patients with FGFR GAs had a better OS with FGFR-targeted therapy compared with standard treatment ( P = .01). BAP1 mutation was the most common coexisting mutation without prognostic impact, whereas TP53 ( P = .04) and CDKN2A/B ( P = .04) were correlated with a shorter OS. Conclusion CCA with FGFR GAs represents a unique subtype occurring in younger patients with an indolent disease course. FGFR-targeted therapy may have a positive impact on OS in this subgroup.

Primary sclerosing cholangitis (PSC) is a risk factor for cholangiocarcinoma (CCA) and gallbladder carcinoma (GBCa). Surveillance for GBCa is recommended, but the clinical utility of surveillance for other hepatobiliary cancers (HBCa) in PSC, namely CCA and hepatocellular carcinoma (HCC), remains unclear. We aimed to determine whether surveillance is associated with better survival after diagnosis of HBCa in patients with PSC. Medical records of PSC patients seen at the Mayo Clinic Rochester from 1995 to 2015 were reviewed. Patients were included if they had ≥1 year of follow‐up and developed HBCa. Patients were categorized according to their surveillance status (abdominal imaging, carbohydrate antigen 19‐9, and alpha‐fetoprotein). The primary endpoints were HBCa recurrence, HBCa‐related death, and all‐cause mortality. Overall survival was assessed by the Kaplan‐Meier survival method; HBCa‐related survival was assessed using competing risk regression. Tests of significance were two‐tailed, and a P value <0.05 was considered statistically significant. From 1995 to 2015, a total of 79 of 830 PSC patients were diagnosed with HBCa. Cumulative follow‐up was 712 and 283 person‐years pre‐ and post‐HBCa diagnosis, respectively. Seventy‐eight percent of patients (54/79) developed CCA, 21% (17/79) HCC, 6% (5/79) GBCa, 3% (2/79) both CCA and HCC, and 1% (1/79) both HCC and GBCa. Fifty‐one percent (40/79) were under HBCa surveillance, and 49% (39/79) were not. Patients in the surveillance group had significantly higher 5‐year overall survival (68% versus 20%, respectively; P < 0.001) and significantly lower 5‐year probability of experiencing an HBCa‐related adverse event (32% versus 75%, respectively; P < 0.001) compared with the no‐surveillance group. Conclusion: This study demonstrates that HBCa surveillance significantly improves outcomes, including survival, in patients with PSC. (Hepatology 2018;67:2338‐2351).

Purpose No standard treatment exists for patients with cholangiocarcinoma for whom first-line gemcitabine-based therapy fails. Fibroblast growth factor receptor 2 ( FGFR2) fusions/translocations are present in 13% to 17% of intrahepatic cholangiocarcinomas. BGJ398, an orally bioavailable, selective pan-FGFR kinase inhibitor, has shown preliminary clinical activity against tumors with FGFR alterations. Methods A multicenter, open-label, phase II study ( ClinicalTrials.gov identifier: NCT02150967) evaluated BGJ398 antitumor activity in patients age ≥ 18 years with advanced or metastatic cholangiocarcinoma containing FGFR2 fusions or other FGFR alterations whose disease had progressed while receiving prior therapy. Patients received BGJ398 125 mg once daily for 21 days, then 7 days off (28-day cycles). The primary end point was investigator-assessed overall response rate. Results Sixty-one patients (35 women; median age, 57 years) with FGFR2 fusion (n = 48), mutation (n = 8), or amplification (n = 3) participated. At the prespecified data cutoff (June 30, 2016), 50 patients had discontinued treatment. All responsive tumors contained FGFR2 fusions. The overall response rate was 14.8% (18.8% FGFR2 fusions only), disease control rate was 75.4% (83.3% FGFR2 fusions only), and estimated median progression-free survival was 5.8 months (95% CI, 4.3 to 7.6 months). Adverse events included hyperphosphatemia (72.1% all grade), fatigue (36.1%), stomatitis (29.5%), and alopecia (26.2%). Grade 3 or 4 treatment-related adverse events occurred in 25 patients (41%) and included hyperphosphatemia (16.4%), stomatitis (6.6%), and palmar-plantar erythrodysesthesia (4.9%). Conclusion BGJ398 is a first-in-class FGFR kinase inhibitor with manageable toxicities that shows meaningful clinical activity against chemotherapy-refractory cholangiocarcinoma containing FGFR2 fusions. This promising antitumor activity supports continued development of BGJ398 in this highly selected patient population.

Genotype, particularly Ras status, greatly affects prognosis and treatment of liver metastasis in colon cancer patients. This pilot aimed to apply word frequency analysis and a naive Bayes classifier on radiology reports to extract distinguishing imaging descriptors of wild-type colon cancer patients and those with v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. In this institutional-review-board-approved study, we compiled a SNaPshot mutation analysis dataset from 457 colon adenocarcinoma patients. From this cohort of patients, we analyzed radiology reports of 299 patients (> 32,000 reports) who either were wild-type (147 patients) or had a KRAS (152 patients) mutation. Our algorithm determined word frequency within the wild-type and mutant radiology reports and used a naive Bayes classifier to determine the probability of a given word belonging to either group. The classifier determined that words with a greater than 50% chance of being in the KRAS mutation group and which had the highest absolute probability difference compared to the wild-type group included: “several”, “innumerable”, “confluent”, and “numerous” (p < 0.01). In contrast, words with a greater than 50% chance of being in the wild type group and with the highest absolute probability difference included: “few”, “discrete”, and “[no] recurrent” (p = 0.03). Words used in radiology reports, which have direct implications on disease course, tumor burden, and therapy, appear with differing frequency in patients with KRAS mutations versus wild-type colon adenocarcinoma. Moreover, likely characteristic imaging traits of mutant tumors make probabilistic word analysis useful in identifying unique characteristics and disease course, with applications ranging from radiology and pathology reports to clinical notes.