Clinicopathological Characteristics of Microscopic Tubal Intraepithelial Metastases from Adenocarcinoma and Small Cell Neuroendocrine Carcinoma of the Uterine Cervix.

Background/aimSome metastatic tumors that involve the fallopian tube show intraepithelial spread, mimicking primary tubal neoplasm and representing a potential diagnostic pitfall. In this study, we aimed to investigate the clinicopathological characteristics of tubal intraepithelial metastasis (IEM) from cervical carcinoma.Patients and methodsWe analyzed the clinical features, histological features, and immunophenotypes of IEMs in five patients with cervical carcinoma.ResultsThis study included usual-type (1/5), mucinous-type (1/5), and gastric-type (2/5) endocervical adenocarcinomas and small cell neuroendocrine carcinoma (1/5) cases. None of the patients had ovarian metastasis, but metastatic tumor cells spread along the tubal mucosal surface and partially replaced the lining epithelium. Histological features of metastatic tumors closely resembled those of the primary tumors in all cases.ConclusionTubal IEM can mimic various tubal lesions including serous tubal intraepithelial carcinoma. Morphological consistency between the primary and metastatic tumors and immunostaining help guide the differential diagnosis of challenging intraepithelial lesions of the fallopian tube.