IMMUNOHISTOCHEMICAL STUDY OF 100 PANCREATIC TUMORS IN 28 PATIENTS WITH MULTIPLE ENDOCRINE NEOPLASIA, TYPE-I

One hundred pancreatic tumors ranging in size from 0.3 to 7 cm were st udied in 28 patients (17 male and 11 female patients, mean age 35 year s) with multiple endocrine neoplasia, type I. An immunohistochemical s tudy was performed on deparaffinized sections using the following anti bodies: neuron-specific enolase, chromogranin A or synaptophysin, insu lin, glucagon, somatostatin, pancreatic polypeptide (PP), vasoactive i ntestinal peptide (VIP), gastrin, adrenocorticotropic hormone, alpha-s ubunit of human chorionic gonadotropin, gonadotropin-releasing factor, serotonin, and calcitonin. Among the 100 tumors (all multiple), seven were unclassified, 10 were plurihormonal, and 83 produced a predomina nt hormonal secretion (with 50-90% of the same cell type), including 3 7 ''A-cell tumors'' (glucagon). 27 ''B-cell tumors'' (insulin), 11 PP- cell tumors, one G-cell tumor (gastrin) and one vasoactive intestinal peptide (VIP)-cell tumor. These multiple tumors had a different predom inant hormonal secretion in the same patient in 23 of the 28 cases. Th ere was a preferential association of A-cell turner and B-cell tumor, Hyperplasia of the islets of Langerhans was not detected in adjacent p ancreas. Nesidioblastosis was observed in 30% of cases.