Carcinoids of the pancreas - An analysis of 156 cases

BACKGROUND. The aim of the current study was to clarify the actual clinicopathologic status of extremely rare pancreatic carcinoids. To date, statistical evaluation of such carcinoids has been hampered because an insufficient number of cases has prevented any reliable statistical analyses. METHODS. The Niigata Registry for Gut-Pancreatic Endocrinomas contains a total number of 156 cases of pancreatic carcinoids among 165 endocrinocarcinomas registered worldwide. This figure of 156 cases comprises 144 typical and 12 atypical carcinoids, which were compared statistically with carcinoids in other representative sites, according to various clinicopathologic criteria. RESULTS. Pancreatic carcinoids made up 1.4% of the total number of registered cases (n = 11,343) and were characteristic in the following five ways. 1) They exhibited a high metastatic rate (66.7%), somewhat lower than that for the ileocecum (76.1%), identical to that for the ileum (66.9%), and far higher than that for the total average of 35.7%. 2) They displayed the largest average tumor size (68.6 mm), followed by that for the ovary (68.2 mm), and ileocecum (46.5 mm) against a total average of 30.2 mm. 3) They revealed a relatively high incidence of the carcinoid syndrome (23.3%), almost equal to that for the ileocecum (24.1%), and exceeded by that for the small intestine (35.8%), when compared with that for the total average of 11.0%. 4) They showed a high rate of immunohistochemical detection for serotonin (92.9%), lower than that for the testicle (100.0%), but higher than the total average of 54.9%. 5) Five-year survival rate was extremely low (28.9% +/- 16.7%) compared with those for the appendix (89.7% +/- 2.0%) and the small intestine (82.1% +/- 3.3%). It was noteworthy that silver impregnations in the pancreatic carcinoid series indicated a result identical to that for the total average: Grimelius argyrophilia, 84.8% versus 85.4%; argyrophil cell type, 59.1% versus 58.5%; and argentaffin cell type, 22.7% versus 22.3%. CONCLUSION. It may be said that in the treatment of patients with pancreatic carcinoids, appropriate procedures should be carried out with these distinguishing characteristics always kept in mind.