Abstract

A rare case of primary choriocarcinoma of the jejunum occurred in a 45 year old Chinese man. This tumour was associated with massive melaena and a markedly raised serum human chorionic gonadotrophin (beta-hCG) concentration. Necropsy examination showed no primary lesion in other possible sites including testes, mediastinum, and pineal gland. Histologically, the tumour showed morphology typical of choriocarcinoma with no adenocarcinomatous element identified. The presence of choriocarcinoma in non-gonadal sites may be explained by retrodifferentiation or metaplasia of a conventional carcinomatous component to primitive trophoblasts. Serum beta-hCG level may represent a useful marker in earlier diagnosis and monitoring of this potentially treatable disease.