Clinical and laboratory data for nine patients with hepatocellular fibrolamellar carcinoma treated at our institution have been summarized with emphasis on the relevance of plasma neurotensin levels as a tumor marker. The mean age of the patients was 22 years. Seven underwent hepatic resection, and two of these had later surgical removal of recurrent disease. Plasma neurotensin levels were initially elevated in five of the seven patients in whom it was measured. Neurotensin levels were within normal limits in three of four patients with recurrent disease, but were elevated in one patient who also had elevated plasma neurotensin levels preoperatively. In addition, a review of 80 patients reported since 1980 was performed. The mean age of these patients was 23 years, and only 6 percent were older than 50. The male to female ratio was 3:4. Eight percent were positive for hepatitis B antigen and 11 percent had elevated alpha-fetoprotein levels. Four percent had cirrhosis of the liver. The resectability rate was 58 percent. Five year survival for patients who underwent hepatic resection was 56 percent. Patients treated nonsurgically had a median survival of 13 months, and none of these patients lived for 5 years. Fibrolamellar hepatoma seems to be a distinct clinical entity that mainly occurs in young patients. The prognosis in patients treated with a curative resection is good. Plasma neurotensin levels may be of value as a tumor marker, but further studies are necessary to substantiate this theory.