ECL cell tumor and poorly differentiated endocrine carcinoma of the stomach: Prognostic evaluation by pathological analysis

Background & Aims: Gastric endocrine tumors show a wide spectrum of clinical behavior, and prognostic assessement of individual tumors is difficult. The aims of this work were to identify predictors of tumor malignancy and patient outcome and to provide a rationale for treatment guidelines. Methods: Gastric endocrine tumors (86 enterochromaffin-like cell carcinoids and 16 poorly differentiated carcinomas) were investigated for 15 clinicopathologic variables and for expression of Ki67, P53, and BCL-2 proteins. Data were analyzed by univariate and multivariate statistics for evidence of tumor malignancy and patient survival. Results: Histological grades 2 and 3, size ≥3 cm, 9 or more mitoses, or ≥300 Ki67-positive cells per 10 high-power fields identified 26 of 33 (79%) malignant (metastatic or deeply invasive) tumors, and size