Percutaneous biopsy of portal vein thrombus: A new staging technique for hepatocellular carcinoma

OBJECTIVE. Accurate staging of hepatocellular carcinoma is necessary to determine appropriate treatment. In particular, neoplastic invasion of the portal vein is a contraindication for hepatic resection or transplantation. Unfortunately, imaging cannot always differentiate benign from malignant portal vein thrombi. We therefore undertook a study to determine the efficacy and safety of sonographically guided percutaneous biopsy of portal vein thrombi as a staging technique for patients with hepatocellular carcinoma. SUBJECTS AND METHODS. We performed percutaneous biopsy of portal vein thrombi in 12 men and two women (43-76 years old) who were being considered for hepatic resection or transplantation. All of the patients had hepatic cirrhosis and 13 had histologically proved intrahepatic hepatocellular carcinoma. Biopsies were performed under continuous color Doppler sonographic guidance by using 20-gauge aspiration needles with occlusive stylets. Each needle was positioned with its tip embedded in the thrombus before the stylet was removed. During aspiration, the needle was carefully controlled to keep its tip within the lumen of the portal vein. To evaluate for possible false- positive results, an additional identical needle was passed in and out of only the hepatic parenchyma in five patients. RESULTS. Adequate specimens were obtained in all 14 patients. Twelve specimens contained malignant hepatocytes, and two contained benign thrombi. One of the benign thrombi in a patient who had a 3-cm hepatocellular carcinoma of the parenchyma was confirmed by examining the resected liver after transplantation. The other patient who had a benign thrombus had no clinical or imaging evidence of hepatocellular carcinoma. No complications associated with biopsy occurred. None of the control needles contained hepatocytes. The patients' discomfort during biopsy was approximately the same as the discomfort experienced during previous liver biopsies. The average length of the procedure was 20 min. CONCLUSION. Sonographically guided percutaneous biopsy of portal vein thrombi is a safe, accurate, useful, and well-tolerated diagnostic procedure for the staging of hepatocellular carcinoma.