Optimal postoperative adjuvant treatment strategy for HBV-related hepatocellular carcinoma with microvascular invasion: a propensity score analysis.

Background: Microvascular invasion (MVI) is the most important risk factor associated with early postoperative recurrence in patients with hepatocellular carcinoma (HCC). However, the efficacy of postoperative adjuvant treatment for preventing recurrence in HCC patients with MVI has not been assessed. This study investigated the efficacy of postoperative adjuvant radiotherapy (RT) and transcatheter arterial chemoembolization (TACE) in HCC patients with MVI. Materials and methods: From July 2008 to December 2016, 117 hepatitis B virus (HBV)-related HCC patients with MVI were retrospectively divided into two groups based on postoperative adjuvant treatments. Propensity score matching (PSM) was performed to adjust for significant differences in baseline characteristics. Relapse-free survival (RFS) and overall survival (OS) of the two groups were analyzed before and after PSM. Results: Of all patients, the RT group had significantly smaller tumor size and milder MVI classification. PSM analysis created 46 pairs of patients. After matching, the two groups of patients were similar in baseline characteristics. Multivariate analysis indicated that tumor size, MVI classification, and postoperative treatment strategies were independently associated with RFS; tumor size and MVI classification were independently associated with OS. Similar multivariate analysis results were demonstrated after matching propensity score. Survival analysis revealed that the estimated median RFS and OS of patients with RT and TACK were 25.74 +/- 8.12 vs 9.18 +/- 1.67 months (P=0.003) and 60.69 +/- 7.36 vs 36.53 +/- 5.34 months (P=0.262), respectively. The RT group had significantly longer RFS than the TACE group. Conclusion: Postoperative adjuvant RT offers better RFS for HCC patients with MVI than TACE.