Characteristics of hepatocellular carcinoma associated with extrahepatic primary malignancies in southern Japan

Objectives: This study was conducted to clarify the characteristics of patients with extrahepatic primary cancers (EHPC) associated with hepatocellular carcinoma (HCC), as well as to investigate the influence of EHPC on both patient survival and disease-free survival after hepatic resection. Methods: Forty-one of 463 patients who underwent hepatic resection were included. The clinicopathological factors, including survival, were compared between patients with and without EHPC. We also compared the same factors among the prehepatectomy, synchronous, and posthepatectomy groups. Different types of extrahepatic cancers were also investigated in detail. Results: Gastric and colorectal cancers were the most common EHPC. No definite relationship was observed between HCC and other specific cancers such as B-cell lymphoproliferative disorders. There also were no differences in either the liver function tests, alpha-fetoprotein, or prognostic pathological indicators such as portal vein invasion and intrahepatic metastases. In addition, we found no difference in patient survival between the patients with and without EHPC. However, disease-free survival rates in patients with EHPC were significantly higher than in those without EHPC. Patients in the prehepatectomy group were older than those in the synchronous and posthepatectomy groups, and no positive hepatitis B surface antigen was found in the prehepatectomy group. Patient survival was significantly higher in the posthepatectomy group than in the prehepatectomy group; however, no significant difference in disease-free survival was found among the three groups. Only one patient died of EHPC. Conclusions: No specific clinicopathological factors were observed in patients with HCC associated with EHPC. Furthermore, EHPC had no adverse effect on either patient survival or disease-free survival after hepatic resection. The predominant cancer was gastric cancer, whereas the most frequent cause of death was HCC itself. Therefore, a strict follow-up of HCC-as well as screening for the most common cancers, such as gastric cancers in southern Japan-should be required for patients with HCC associated with EHPC.