HIGH GRADE SEROUS CARCINOMA OF THE FALLOPIAN TUBE PRESENTING AS A CERVICAL MASS: A DIAGNOSTIC CHALLENGE

Abstract

Background: High grade serous carcinoma (HGSC) is a highly aggressive Müllerian neoplasm that most commonly arises from the fallopian tube fimbriae or ovary and spreads to the peritoneum. Secondary metastasis to the uterine cervix presenting as a clinically apparent cervical mass is an exceptionally rare occurrence that can mimic primary cervical carcinoma both clinically and histologically, posing significant diagnostic difficulty.

Case Presentation: We report a case of a 50-year-old postmenopausal woman who presented with per-vaginal bleeding. Per speculum examination revealed an exophytic cervical growth. Initial biopsy of the cervical lesion was interpreted as poorly differentiated squamous cell carcinoma. Radical hysterectomy was subsequently performed. Gross examination revealed a greyish-white exophytic cervical mass with concurrent involvement of the right fallopian tube. Histopathology demonstrated pleomorphic tumour cells arranged in clusters, nests, and micropapillary formations with abundant mitotic figures and necrosis. Immunohistochemical staining showed strong diffuse positivity for WT-1, PAX8, and CK7 in both the cervical and fallopian tube lesions, confirming Müllerian serous origin and supporting the fallopian tube as the primary site.

Conclusion: This case illustrates a rare phenomenon: primary fallopian tube HGSC presenting with clinically dominant cervical metastasis, initially misdiagnosed as squamous cell carcinoma of the cervix. It underscores the critical importance of an expanded immunohistochemical panel and comprehensive specimen evaluation in cases where tumour morphology appears inconsistent with a primary site diagnosis.