Microwave ablation for the treatment of hepatocellular carcinoma that met up-to-seven criteria: feasibility, local efficacy and long-term outcomes.

<bold>Objectives: </bold>This study aimed to evaluate the feasibility, local efficacy and long-term outcomes of microwave (MW) ablation for the treatment of hepatocellular carcinoma (HCC) that met up-to-seven criteria.<bold>Methods: </bold>Between January 2007 and January 2012, 142 HCC patients with 294 nodules, which conformed to up-to-seven criteria, were enrolled into this retrospective study. All patients were followed up for more than 3 years after receiving MW ablation. Technical success, complications, local tumour progression (LTP) and distant recurrence (DR) were monitored. Recurrence-free survival (RFS), overall survival (OS) and prognostic factors were analysed.<bold>Results: </bold>Primary technical efficacy was achieved in 95.2% (280/294) of the carcinomatous nodules, and major complications occurred in four (2.8%) patients. Among the 294 tumours, LTP was observed in 44 (15.0%) tumours. Among the 142 patients, DR was observed in 97 (68.3%) patients. The estimated OS rates after MW ablation at 1, 3 and 5 years were 97.2%, 75.4% and 50.6%, respectively; and the corresponding RFS rates were 76.1%, 33.1% and 19.5%, respectively.<bold>Conclusions: </bold>MW ablation is a safe and effective treatment with a high rate of primary technical efficacy for patients with HCC that met up-to-seven criteria.<bold>Key Points: </bold>• The first study expanding MW ablation to HCC category beyond Milan criteria. • The first report that used up-to-seven criteria as indications for MW ablation. • HCC of up-to-seven criteria viewed as a subgroup of BCLC stage B. • MW ablation is safe and effective for treating HCC within up-to-seven criteria. • MW ablation is preferable in treating unresectable HCC within up-to-seven criteria. [ABSTRACT FROM AUTHOR]