Laroia, Sandeep

AbstractFinding a feeding vessel with diameter greater than 0.9 mm during transarterial chemoembolization (TACE) for hepatocellular cancer (HCC) has been shown to predict tumor necrosis on subsequent pathology. However, whether this translates into a useful clinical predictor for post-chemoembolization response and survival is unknown. This study aimed to determine whether the presence of an arterial feeder on pre-TACE cross-sectional imaging is associated with treatment response and survival after TACE for unresectable HCC. Retrospective medical record search for all chemo-embolizations performed for HCC from 2015 to 2016 yielded 138 patients who underwent 275 TACE sessions spanning 2011 to 2017. Patients consisted of 98 males (71%) with mean age of 62 (range, 37–86). Each patient underwent an average of two TACE sessions (range, 1–11). Endpoints included target tumor response and overall response defined by the mRECIST criteria, as well as patient survival. Preprocedural MRI/CT was reviewed for the presence of arterial feeder. Multivariable logistic regressions and Cox proportional hazard regressions were used to assess the effects of arterial feeder presence on treatment response and survival, respectively, adjusting for other covariates. Overall response was seen in 69% of patients. Arterial feeder was present on preprocedural cross-sectional imaging for 28% of TACE sessions. Median survival was 26.5 months (interquartile range, 13.2–38.1). The presence of arterial feeder led to better target tumor response (OR = 11.9, p < 0.0001), overall response (OR = 9.3, p < 0.0001), and improved survival (HR = 0.55, p = 0.02). The presence of an arterial feeder on pre-TACE cross-sectional imaging is associated with target tumor response, overall response, and survival after TACE.

TPS276 Background: Immune checkpoint inhibitors have revolutionized the treatment of a number of cancers. In colorectal cancers, their efficacy is limited to mismatch repair deficient or microsatellite stability-high (dMMR/MSI-High) tumors only. These constitute only 4-5% of all metastatic colorectal cancers (mCRC). Novel approaches are needed to make immunotherapy a viable option for mismatch repair proficient or microsatellite stable (pMMR/MSS) tumors. Increasing exposure of neo-antigens to the immune system could be one potential strategy to enhance the response of immunotherapy. Yttrium 90-radioembolization (Y90-RE) in combination with immunotherapy may work synergistically to enhance efficacy of each other. Additionally, radiation can potentially make the tumor microenvironment conducive to effector T-cell recruitment and function. Therefore, we hypothesize and propose the clinical trial of combining immunotherapy with Y90-RE as a feasible and safe strategy that will improve outcomes in patients with mCRC with liver-predominant metastases. Methods: This clinical trial will be conducted as a single-center, open-label, Phase I/II trial to evaluate initially the feasibility and safety of Y90-RE in combination with a fixed dose of immunotherapy (durvalumab) in subjects with liver-predominant, mCRC (Table). It will be offered in the refractory setting. The trial will be performed in 18 subjects with mCRC with liver metastasis and the safety of immunotherapy (durvalumab) with Y90-RE will be investigated in an accelerated titration design. This would allow a maximum tolerated dose with the minimum number of subjects. Correlative studies pertaining to serial circulating tumor DNA (ctDNA - liquid biopsies) testing as well as immune-panel based profiling will be performed alongside pre- and post-biopsies to study changes in the tumor microenvironment. Clinical trial information: NCT04108481. [Table: see text]