Non-functioning endocrine tumors of the pancreas: case report and review of literature

The case is reported of a man with non-functional tumor of the pancreas mimicking a pancreatic adenocarcinoma. CT scan showed an enlargement of the pancreatic head (about 3 cm), described as pancreatic carcinoma. Ca19-9 was over 47. The patient underwent surgery in June 2001 and a duodenopacreatectomy with pylorus preservation was performed. The histopathological staging was: non-functioning endocrine pancreatic tumor NSE, cromogranin A and sinaptophysin positive, insulin and glucagon positive in some foci. Ki-67 p.i. less than 3% . LyInph nodes were negative. No adjuvant therapy was performed. Presently the patient is hospitalized for a pneumothorax related to an enphysema progression, but free from neoplastic disease. Pancreatic endocrine neoplasms (PEN) present different onset teatures with numerous and varied treatment dilemmas. No consensus is actually present in literature as far as prognosis is concerned due to the still unclear definition of PEN malignancies. The histopathological prognostic criteria are: lymph nodes involvement, metastases, vascular invasion, complete resection, size of the primary tumor. Recently, a system has been proposed that has yet to be independently validated. The criteria are: size, mitotic activity, vascular invasion and the tumors are classified as “Inicroadenoma”, “macroadenoma”, “border line”, “low grade carcinoma”. Studies on molecular and genetic features of pancreatic endocrine tumors have also been performed. Investigations were carried out on MENI genes at chromosome llq13, Von Hippel Lindau gene, the 4 genes alterated in ductal pancreatic cancer, (p53, K-ras, p16, DPC4), but despite these efforts, little is still known about PENs genetic anomalies. Presently a prognostic histopathological classification may represent a reliable system to approach these neoplasms, but future genetic studies should unable us to better define the prognosis and therapy of these unusual types of cancers.