Stromal eosinophilia in colonic epithelial neoplasms

OBJECTIVE: The purpose of this retrospective study was to determine the fre quency and intensity of eosinophilia infiltration (or tissue eosinophilia) in the stroma of colonic adenomas, hyperplastic polyps, and colorectal aden ocarcinomas. Eosinophilic infiltration in various malignancies has been rep orted but has not been evaluated in benign colorectal adenomas and hyperpla stic polyps. METHODS: We analyzed 488 colonic neoplasms:176 tubular adenomas, 55 tubulov illous adenomas, 82 villous adenomas, 15 early carcinomas in polyps, 95 inv asive adenocarcinomas, and 65 hyperplastic polyps for the presence of eosin ophilic infiltration. The eosinophilic infiltration was graded as negative (less than or equal to 5%), mild to moderate (>5-40%), or marked (>40%), de pending on the percentage of eosinophils relative to total inflammatory cel ls in the stroma. RESULTS: Mild to moderate eosinophilia was noted in 75% of all adenomas. Th e transitional zone in all cases of invasive adenocarcinoma (zone between n ormal tissue and adenocarcinoma) revealed a high percentage of tissue eosin ophilia. There was a striking absence of TE in the stroma of invasive adeno carcinomas. Only 5% of hyperplastic polyps had any eosinophilic infiltratio n. CONCLUSIONS: These data suggest that, in the spectrum of colonic neoplasms, stromal eosinophilia is most prominent in adenomas and seems to decrease w ith progression through the adenoma-carcinoma sequence. The ramifications o f this study may alter management plans and provide some prognostic informa tion for clinical evaluation. (C) 2000 by Am. Cell. of Gastroenterology.