Mixed ductal-pancreatic polypeptide-cell carcinoma of the pancreas.

AIMS

Mixed ductal-endocrine carcinomas of the pancreas are rare tumours with 10 cases reported in the English literature. We report the first case with a polypeptide-cell component.

METHODS AND RESULTS

: The tumour was fortuitously discovered in a 72-year-old woman during the exploration of an endometrial adenocarcinoma. It measured 100 mm and was located in the tail of the pancreas. On microscopic examination two intermingled endocrine and exocrine components were present. The endocrine component consisted of trabeculae and solid nests composed of cells immunoreactive for chromogranin A, synaptophysin and pancreatic polypeptide, but negative for p53 and Bcl-2 proteins. The exocrine component was composed of tubules lined by atypical cylindrical cells immunoreactive for CK19, CEA, p53 and Bcl-2. The stroma of the endocrine component contained amyloid deposits.

CONCLUSION

Mixed ductal-endocrine carcinomas of the pancreas are often described in middle-aged patients. The tumours are usually large and located in the head of the pancreas. An endocrine syndrome is rare and the prognosis is often unfavourable. We report the first case of mixed endocrine-exocrine carcinoma of the pancreas with a pancreatic polypeptide-cell component. The histogenesis of mixed carcinoma of the pancreas is still uncertain but the over-expression of p53 and Bcl-2 could play a major role in the neoplastic progression of the ductal component.