Hepatectomy Combined with Diaphragmatic Resection for Hepatocellular Carcinoma with Diaphragmatic Involvement: A Propensity Score-Matched Analysis

Purpose We evaluated the short- and long-term surgical outcomes of hepatectomy combined with diaphragmatic resection for hepatocellular carcinoma (HCC) with diaphragmatic involvement. Methods We retrospectively reviewed the surgical outcomes of HCC patients with diaphragmatic resection (DR group) and HCC patients without diaphragmatic resection (non-DR group). We applied 1:1 propensity score matching (PSM) to these subjects. Results The study included 46 patients in DR group and 828 patients in non-DR group. The DR group cases were pathologically more advanced, and both overall and relapse-free survival among the patients in this group with pathological diaphragmatic invasion were similar to cases with pathological diaphragmatic fibrous adhesion. There were 40 patients from each group subjected to PSM. In these matched cohorts, there was no statistically significant difference between the two groups regarding perioperative outcomes, overall survival, and relapse-free survival. Multivariate analyses of our matched HCC patients revealed that alpha-fetoprotein expression and tumor size were independent prognostic factors for overall survival and poor differentiation for relapse-free survival, whereas neither diaphragmatic invasion nor diaphragmatic resection were prognostic indicators. The most frequent site of recurrence in non-DR group was the liver, whereas the most frequent site of recurrence in DR group was the lung before and after PSM. Conclusions The short- and long-term surgical outcomes of DR HCC cases are equivalent to their non-DR counterparts under a matched clinicopathological background. Hepatectomy combined with DR is an acceptable treatment for HCC with either diaphragmatic fibrous adhesion or diaphragmatic invasion.