[Histological classification of schistosome egg polyp and its clinical significance: an analysis of 272 cases]

272 cases of schistosome egg polyp collected from the mass-screening for colon carcinoma in Jiashan County have been divided into 3 groups (i.e. fibrous type, mixed type and epithelial hyperplastic type) according to the amount of fibrous stroma. The epithelial hyperplastic type (E type) was characterized by gland elongation, hypertrophy, variation in size, disorder in arrangement and high percentage of atypical hyperplasia (64.9%). Coexistence and transitional change of hyperplastic and adenomatous glands were noticed. By HID/AB staining, sialomucin increased prominently in E type. CEA and PNA receptors by ABC method were detected in 18/20 and 6/20 of E type respectively. The results of mucin expression were similar to those of adenoma. It is likely that the spectrum of E type polyp, atypical hyperplasia and adenoma exists. The authors suggest that patients with E type polyp of schistosome egg, especially those with atypical hyperplasia, should be treated as "risky" population of colon carcinoma.