Histological tumor micronecrosis in resected specimens after R0 hepatectomy for hepatocellular carcinomas is a factor in determining adjuvant TACE: A retrospective propensity score-matched study.

BACKGROUND: Tumor micronecrosis is a less investigated pathological feature of hepatocellular carcinoma (HCC). This study was aimed at evaluating the value of micronecrosis for guiding adjuvant transcatheter arterial chemoembolization (TACE) in HCC management. METHODS: We retrospectively reviewed the data of patients with HCC who underwent curative liver resection in our center from 2014 to 2018. The patients were divided into micronecrosis (+) and micronecrosis (-) groups. In each group, overall survival (OS) and disease-free survival (DFS) were compared between patients who underwent adjuvant TACE and those who did not. Propensity score matching (PSM) was conducted at a ratio of 1:1 to control selection bias. Univariate and multivariate analyses were performed to determine independent prognostic factors. Mass cytometry was applied to compare the immunological status of HCCs between the two groups. RESULTS: A total of 897 patients were included, with 417 and 480 patients in the micronecrosis (+) and micronecrosis (-) groups, respectively. No significant difference was detected in baseline parameters after PSM. In the micronecrosis (+) group, patients who underwent adjuvant TACE had significant longer OS than did those who did not (P = 0.004). However, patients in the micronecrosis (-) group did not benefit from adjuvant TACE. Although adjuvant TACE prolonged the DFS of patients with severe micronecrosis (P = 0.034), it may adversely affect the DFS of patients without micronecrosis (P = 0.131). Multivariate analysis showed that TACE was an independent prognostic factor for patients with micronecrosis but not for those without micronecrosis. The abundance of exhausted and regulatory T cells was significantly higher in patients with micronecrosis. CONCLUSIONS: For HCC patients with micronecrosis, adjuvant TACE after curative resection could improve the prognosis, while its survival benefits were limited in HCC patients without micronecrosis. TACE should be selectively performed in patients with micronecrosis, especially those with an Nscore = 2. The immunosuppressive status of HCC patients with micronecrosis may explain the effectiveness of adjuvant TACE in such scinario.