CARCINOID-TUMORS OF THE PANCREAS - STATUS-REPORT BASED ON 2 CASES ANDREVIEW OF THE WORLDS LITERATURE

Conclusion. The diagnosis of a pancreatic carcinoid should be based on the measurement of serotonin in serum or its demonstration in the tum or and/or by the measurement of its derivative (5-HIAA) in urine. Carc inoid of the pancreas is a rare but definite entity; usually having me tastasized by the time of diagnosis. The term ''serotonin-producing tu mor of the pancreas'' has been suggested as an alternative designation for ''pancreatic carcinoid.'' Background. The literature on carcinoid tumors of the pancreas is confusing because much of it preceded the d evelopment of the more specific immunological, chemical and staining t echniques currently available. Methods. 43 case reports were collected from the world's literature, based on a demonstrable pancreatic neuro endocrine tumor plus a positive finding of at least one of the followi ng without another dominant hormone being demonstrated: elevation of 5 -Hydroxytryptamine (5-HT) (serotonin) in the serum or detected in tumo r tissue, and/or elevation of 5-Hydroxyindole acetic acid (5-HIAA) in the urine. In addition to these two hormone-specific assays, informati on was collected on the silver-staining properties of the tumor; prope rties which have traditionally been associated with carcinoid tumors. Positive silver staining in tumor cells (argyrophilic and/or argentaff in reaction) is strongly indicative of the carcinoid tumor but the fin dings are less specific than the hormone assays and immunohistologic s tains. Results. In this review of 43 cases, including two current ones , the pancreatic carcinoid tumor has the following important features: 1. It is a rare tumor that is usually diagnosed late when the tumor i s large and has metastasized. Thirty-eight (88.4%) have been malignant . They are, therefore, associated with a high incidence of the ''carci noid syndrome.'' 2. To date, prognosis in therapy is poor, based on de layed diagnosis, a resultant low incidence of resectability, and an un certain duration of survival after resection. 3. Pancreatic carcinoid tumors remain difficult to differentiate from other endocrine tumors. The measurement of urinary 5-HIAA excretion or the demonstration of el evated serotonin level in the tumor or in serum is essential to its di stinction. Silver staining of the tumor, although of historic importan ce, has been superceded by the hormone-specific studies. 4. To disting uish it from other endocrine tumors of the pancreas, the terms ''pancr eatic serotoninoma'' or ''serotonin-producing tumor of the pancreas'' have been suggested as possible alternatives. Its growth characteristi cs may be related more to its cell of origin than to its extent of hor mone secretion. Not all of the tumors result in recognizable hypersero toninemia.