Although age, stage, region of origin, and urinary level of 5-hydroxyindoleacetic acid predicted survival by univariate analysis, only the latter three were independent predictors of survival by multivariate analysis. Of the patients with metastatic disease at diagnosis, those with midgut tumors had better survival than those with foregut or hindgut tumors. Although region of origin is certainly an important factor in determination of prognosis, stage of disease at presentation is more predictive of survival. Pancreatic and midgut carcinoids are metastatic at diagnosis more often than those arising in other locations, leading to a worse overall prognosis. Among patients with distant metastases, patients with midgut primary tumors have improved survival despite increased hormone production compared with patients with tumors arising in other primary sites.
Tissue growth depends on both cell proliferation and cell death.
This study was designed to examine the growth characteristics of rectal carcinoid tumors. Fifty rectal carcinoid tumors were studied clinicopathologically and experimentally. EGF receptor expression was examined by a colorimetric in situ mRNA hybridization technique. The Ki-67 LI indicated a low cellular proliferative activity in rectal carcinoid tumors. AI was very low, and was significantly correlated with proliferative rate.