Postoperative radiotherapy following null-margin hepatectomy in patients with hepatocellular carcinoma adhering to the major vessels: A propensity score-matched survival analysis cohort study

Background & Aims: This study aims to analyze the prognosis of null-margin (<= 1.0 mm) hepatectomy (NH) in patients with hepatocellular carcinoma (HCC) adhering to the major vessels and explore the value of postoperative radiotherapy (RT) in these patients. Methods: HCC patients who underwent null-margin or wide-margin (>= 1.0 cm) hepatectomy (WH) by our team from January 2008 to March 2016 were recruited and analyzed retrospectively. The patients were divided into the NH, NH + RT, and WH groups. Propensity score matching (PSM) was performed to balance baseline characteristics. Results: A total of 357 patients were recruited. Of these, 84, 49, and 224 patients were given NH alone, NH plus RT, and WH, respectively. After PSM, the 5-year overall survival (OS) and disease-free survival (DFS) rates of the NH group were significantly worse than those of the WH group (51.5 % vs. 71.4 %, P = 0.003; 32.2 % vs. 50.9 %, P = 0.005). The OS and DFS rates of the NH + RT group were significantly higher than those of the NH group (75.6 % vs. 56.1 %, P = 0.012; 46.6 % vs. 30.2 %, P = 0.015) and similar to those of the WH group (75.6 % vs. 75.1 %, P = 0.354; 46.6 % vs. 56.6 %, P = 0.717). In addition, patients in the NH + RT group experienced significantly lower early (P = 0.023) and intrahepatic (P = 0.015) recurrences than those in the NH group. Conclusions: Patients with HCC adhering to the major vessels who underwent NH alone had a poorer prognosis, and the addition of RT to NH provide a significant survival benefit for these patients, which may yield outcomes comparable to the efficacy of WH.