Untangling the Labyrinth: An Integrated View of the Mesothelial and Epithelial Linings of the Female Adnexa Based on Newly Characterized Anatomic and Histologic Junctions.

Epithelial junctions such as the cervical transformation zone and the gastroesophageal and anorectal junctions are hotspots for carcinogenesis. Three junctional regions in the female adnexa have been recently described and characterized: the fallopian tube-peritoneal junction at the distal end of the fimbriae, the ovarian surface epithelial-peritoneal junction at the ovarian hilus, and the fimbria ovarica connecting the distal fallopian tube to the ovarian surface. As most extrauterine high-grade serous carcinomas have been determined to arise in the distal fallopian tube, this new paradigm renders such junctions of critical importance in understanding the anatomic and histologic origin and pathogenesis of these tumors. This review contextualizes these junctions to promote a new understanding of adnexal anatomy and histology in relation to current concepts of tubo-ovarian carcinogenesis.