Increased incidence of bone metastases in hepatocellular carcinoma

Objectives Recently, we often encounter hepatocellular carcinoma patients w ith bone metastases. We therefore examined the changes in the incidence of bone metastases in hepatocellular carcinoma from 1978 to 1997 and tried to identify the characteristic clinical features. We also discuss the reasons for the increased incidence of bone metastasis in hepatocellular carcinoma. Methods A total of 673 patients with hepatocellular carcinoma during the pe riod 1978-1997 were studied. Bone metastasis was screened by bone scintigra phy, and bone lesions were confirmed by plain radiography, computed tomogra phy and/or magnetic resonance imaging. The serum levels of the C-terminal t elopeptide of type 1 collagen, which represent osteoclastic bone resorption , were also measured. Results The incidence of bone metastasis during the decade 1988-1997 was si gnificantly higher than that during the period 1978-1987. The median surviv al time of patients with hepatocellular carcinoma during 1988-1997 was also significantly longer than that during 1978-1987. Portal thrombus was found in about half of the patients with bone metastases. The most common site o f bone metastases was the vertebra followed by the pelvis, rib and skull in that order. All bone lesions depicted by plain radiograph, computed tomogr aphy and/or magnetic resonance imaging were of the osteolytic type, and the serum levels of C-terminal telopeptide of type 1 collagen were significant ly elevated in the patients with bone metastases. Conclusions The increased incidence of bone metastasis in hepatocellular ca rcinoma in the decade 1988-1997 is first attributed to the prolonged surviv al rate of hepatocellular carcinoma patients due to recent progress in both the diagnosis and treatment of the disease. Dissemination of hepatocellula r carcinoma cells to the vertebra through the portal vein-vertebral vein pl exuses due to the presence of portal thrombus and/or portal hypertension ma y be related to a higher incidence of bone metastasis in hepatocellular car cinoma. Both an early diagnosis and timely treatment of bone metastases are thus called for in the follow-up of hepatocellular carcinoma patients. (C) 2001 Lippincott Williams & Wilkins.