| [ Summary ] |
Out of 12,152 reported cases of endocrinocarcinomas recorded in the Niigata Registry for Gut-Pancreatic Endocrinomas, 345 colonic, 1,730 rectal, 1,047 appendiceal and 94 ileocecal cases were selected for the present analysis. These cases were divided into two main groups of carcinoids and variant neoplasms, the latter including endocrine SCC, ECC, NEC, etc. The carcinoid group was composed of two series of typical carcinoids and atypical varieties. Statistical analyses, with a P-value evaluation were performed chiefly on cases with metastases, postoperative recurrence, and those with five-year survival rates. Special emphasis was placed on colonic and rectal cases in the carcinoid group. Limited carcinoid cases with submucosal invasion (sm cases) were analyzed in detail for their rates of metastases in relation to tumor-size, calculated on a millimeter scale. In rectal sm cases (n=768), those with lesions of 5 mm or less, showed a metastasis rate of 3.7% in comparison with 6.0% for all sm cases in the same tumor size category in the digestive system (n=1,559). The rate of recurrence after curative resection of carcinoid lesions was 16.5% in the colon (n=115), and 10.7% in the rectum (n=923) as compared to 9.8% in the entire number of carcinoid cases of the digestive system (n=3,481). The five-year survival rate for rectal carcinoid cases (n=823) was 63.5% for those with metastases (n=199) and 98.4% for those without metastases (n=624), exhibiting significant statistical differences between these two (p<0.0001). |