Primary endocrine tumours of the liver

BACKGROUND: In patients with hepatic endocrine tumours, a primary neoplasm is not always found elsewhere despite extensive investigations, raising the possibility that the hepatic lesion is the primary tumour. The aim of this study was to assess the incidence, characteristics and prognosis of patients with primary hepatic endocrine tumours. METHODS: Patients with histologically confirmed hepatic endocrine tumours identified since 1993 were reviewed. All those with no primary tumour identified by computed tomography of the thorax, abdomen and pelvis, upper and lower digestive endoscopy, duodenopancreatic endoscopic ultrasonography or somatostatin receptor scintigraphy (SRS) were included. Clinical and tumour characteristics were assessed retrospectively. RESULTS: Of 393 patients with digestive endocrine tumours, 17 (seven men; median age 55 (range 26-69) years) had hepatic endocrine tumours without evidence of an extrahepatic primary lesion either at diagnosis or during a median follow-up of 43 (range 12-108) months. Ten patients had multiple and seven had single tumours. The tumours were non-functional in 13 patients and well differentiated in 14 patients. SRS was positive in the liver in 11 patients. Curative resection was performed in seven. Overall actuarial survival rates were 100, 69 and 51 per cent at 1, 3 and 5 years respectively. Only poor differentiation was associated with an unfavourable outcome (relative risk 20.8; P < 0.001). CONCLUSION: Primary hepatic endocrine tumours were identified in almost 5 per cent of patients with digestive endocrine tumours. Poor differentiation was the only factor associated with unfavourable outcome.