Serologic, radiographic, and tissue-based markers associated with major pathologic response after treatment with neoadjuvant immunotherapy in patients with resectable hepatocellular carcinoma.

Abstract

561 Background: Neoadjuvant immunotherapy can induce a major pathologic response (MPR) in patients with resectable hepatocellular carcinoma (HCC), which may be associated with prolonged recurrence-free survival. This study aimed to understand which variables correlate with achieving an MPR. Methods: Patients with resectable HCC who received either neoadjuvant nivolumab plus ipilimumab or nivolumab alone and underwent surgery were included. 18 patients had baseline and post-treatment computed tomography, alpha-fetoprotein (AFP), and elastography. 17 of these patients had baseline and post-treatment tissue available for immunohistochemistry. Patients were classified into two groups: MPR, defined as necrosis of >70%, and no MPR. Data was summarized using descriptive statistics and compared using Wilcoxon rank sum test. P value <0.05 was considered statistically significant. Results: Statistically significant differences in objective response (OR) and changes in CD8, Granzyme B, and PD-1 expression were identified upon comparison of patients with an MPR to those without an MPR (Table 1). Additionally, numerical differences in baseline tumor size, change in AFP, and both non-tumor and tumor liver fibrosis (at baseline, after treatment, and interim change) were identified upon comparison of patients with an MPR to those without an MPR. Conclusions: Our data show that large baseline tumor size, greater OR, reduction in AFP, increase in liver and tumor fibrosis, and increase in CD8, Granzyme B, and PD-1 expression after receipt of neoadjuvant immunotherapy are associated with achieving an MPR in patients with resectable HCC. [Table: see text]