OBJECTIVETo study the serous lesions of the fimbria of the fallopian tube in patients with pelvic serous adenocarcinoma and investigate its significance in the serous carcinogenesis.

METHODSTo observe the morphological features of the fimbria of the fallopian tube in 43 cases of pelvic serous adenocarcinoma (31 cases of ovarian carcinoma and 12 cases of peritoneal carcinoma). Immunohistochemical examination of p53 expression was performed on samples of 69 fallopian tubes of 40 cases.

RESULTSFimbria carcinoma was identified in 44 tubes in 31 of 43 cases. Fourteen of the carcinoma foci were ≤ 5 mm. In 68.3% of the fimbria carcinomas demonstrated involvement of the mucosa. Twenty eight tubes of 20 cases exhibited intraepithelial carcinoma. Twenty three of 44 tubes of the fibria carcinomas showed fimbria adherence and unclear appearance. The early histological changes of the fimbria epithelium included proliferation of local secretory cells, homogeneity, and straightening of the mucous folds. Clusters of tumor epithelial cells or single gland with atypical features floated between mucosal folds were found in 71.4% of the fimbria with intraepithelial carcinoma. The positive expression rate of p53 in the fimbria carcinomas and the fimbria intraepithelial carcinomas were 86.4% and 60.7%, respectively.

CONCLUSIONSFimbria carcinomas is an important component in pelvic serous adenocarcinomas. The fimbria intraepithelial carcinoma is also very common among the cases of pelvic serous adenocarcinoma. The fimbria may be an important primary site of pelvic serous adenocarcinomas.