Characteristics and predictors of survival outcomes of patients with large pathology-defined T1b hepatocellular carcinoma undergoing resection.

As tumor size increases, the risk of microscopic vascular invasion (MVI) and satellite nodules increases for patients with hepatocellular carcinoma (HCC). However, large pathology-defined T1b (pT1b) HCC (i.e., single tumor > 5.0 cm without MVI) has been noted in a small proportion of patients with HCC undergoing liver resection (LR). We aimed to determine the characteristics and predictors of survival outcomes of this special population. We consecutively included 126 patients with HCC at pathological stage T1b N0M0 of the 8th edition of the American Joint Committee on Cancer staging and a tumor size of > 5.0 cm who underwent LR between 2007 and 2021 at our institution. Variables based on a priori selection, i.e., alpha-fetoprotein (AFP) level, cirrhosis status, resection extent, and tumor differentiation, were included in a multivariate analysis using the Cox proportional hazards model. Of the 126 patients, 27 (21.4%) had cirrhosis, 3 (2.4%) showed poor tumor differentiation, 88 (70.0%) underwent major resection, and 40 (31.7%) had an AFP level of ≥ 20 ng/ml. Five-year overall survival was 78.8% (95% confidence interval [CI] = 78.4%-79.2%); 5-year recurrence-free survival was 60.3% (95% CI = 59.8%-60.8%). Multivariate analysis showed that poor tumor differentiation was the only factor associated with mortality (hazard ratio [HR] = 38.46; 95% CI = 7.577-195.27; p < 0.001) and recurrence (HR = 9.153; 95% CI = 2.371-35.331; p = 0.001). The survival outcomes of this special population were good. About 80% of these patients were non-cirrhotic. Poor tumor differentiation was the only factor associated with survival outcomes.