BACKGROUND The clinical features and prognosis of hepatocellular carcinoma (HCC) with peritoneal metastasis have not been fully evaluated.

AIMS This study aimed to investigate the risk factors, clinical features, and prognosis of HCC with peritoneal metastasis.

METHODS Patients who were diagnosed as HCC with peritoneal metastasis and the same number of randomly selected, risk factor-matched HCC controls without peritoneal metastasis were included. The risk factors and overall survival were compared between peritoneal metastasis-positive and -negative groups after adjustment of other variables.

RESULTS HCC rupture was an independent risk factor for peritoneal metastasis in HCC patients (P = 0.008). When the risk factors (age, sex, Child-Pugh score, and intrahepatic tumor stage) were matched, peritoneal metastasis failed to independently affect overall survival (P = 0.511). In the peritoneal metastasis-positive group, advanced Child-Pugh class [hazard ratio (HR), 1.99; 95% confidence interval (CI), 1.07-3.72; P = 0.030] and progressive intrahepatic HCC status (HR, 19.04; 95% CI, 2.55-142.13; P = 0.004) were independent risk factors for early death. Complications such as ileus, bleeding, and hydronephrosis due to rectovesical mass were reported in 1.5-7.4% in the peritoneal metastasis-positive group.

CONCLUSIONS Peritoneal metastasis was not found to be an independent prognostic factor of HCC, and among HCC patients with peritoneal metastasis, those with advanced Child-Pugh class and with uncontrolled intrahepatic HCC showed poor survival. Therefore, the maintenance of favorable hepatic function and control of intrahepatic HCC should still be emphasized in HCC patients with peritoneal metastasis.