Ninety-three patients with malignant disease underwent orthotopic liver transplantation between May 1968 and April 1987 in the Cambridge/King's College Hospital program. Of 50 patients with primary hepatocellular carcinoma (HCC) (19 with cirrhosis, 31 without cirrhosis, including 7 with fibrolamellar variant), 37 (74%) survived for more than 3 months, and in this group evidence of tumor recurrence was obtained in 24 (64.9%), the longest survivor being 11.8 years post-transplant, and three survived for more than 5 years. Although there is no correlation between the frequency of tumor recurrence and underlying cirrhosis, or histologic type (except fibrolamellar variant), it was observed earlier in those with moderate/poorly differentiated tumors and also when prednisolone and azathioprine was used for immunosuppression. Tumor recurred in all but two of those with peripheral or central cholangiocarcinoma (one alive at 6.1 years) with median survival times of 34 weeks and 56 weeks for the central and peripheral types, respectively. Among the unusual primary tumors, one with epithelioid haemangioendothelioma developed tumor recurrence at 2 years, one of two patients with apudoma is tumor-free at 2.2 years, and the one patient with bile-duct papillary cystadenocarcinoma is alive at 1.7 years. For the secondary hepatic malignancy group, survival times were shorter with little palliation except for two patients with carcinoid syndrome who were free of associated symptoms at 6 and 10 months. Despite the overall high frequency of tumor recurrence in most categories of hepatic malignancy, liver transplantation gave worthwhile survival with a number of patients cured and in the others considerable palliation of symptoms.