High-Grade serous carcinoma of the fallopian tube: two cases presenting as inguinal lymph node metastasis

Abstract

Primary fallopian tube high-grade serous carcinoma (HGSCa) has historically been considered an uncommon neoplasm. Recent evidence, however, suggests that most extrauterine HGSCa arise within the fimbriae of the fallopian tube, via an intraepithelial precursor lesion known as serous tubal intraepithelial carcinoma (STIC), which is thought to metastasise to the ovary and pelvic peritoneum. HGSCa typically present with advanced disease and the prognosis is notoriously poor. Presentation of HGSCa as lymph node metastasis is distinctly unusual, even more so in the absence of detectable pelvic disease. We describe two cases of HGSCa of fallopian tube origin presenting as inguinal lymph node metastasis, both with clinically silent pelvic disease at presentation. Although an uncommon mode of presentation, these cases reinforce the need to maintain a high index of suspicion for HGSCa, even in the absence of gynaecological symptoms. Accurate diagnosis is achievable with careful morphological assessment teamed with an immunoperoxidase panel which includes Wilms’ tumour 1 (WT1) and may provide an opportunity for definitive surgery before bulky pelvic disease supervenes. This new model of tumourigenesis of HGSCa may have significant implications for the management of BRCA mutation carriers and potentially all women undergoing pelvic surgery.