Ovarian Sex Cord-Stromal Tumors: An Update With Emphasis on Genetics, Evolving Entities, and Selected Diagnostic Issues

Ovarian sex cord-stromal tumors are a diverse class of neoplasms including both benign tumors and those with malignant potential. These tumors can cause a variety of diagnostic issues for pathologists due to their morphologic diversity and the relative rarity of some neoplasms in this group. The basic clinicopathologic features of these tumors are well known and illustrated. Thus, herein we discuss select entities, emphasizing recent advances, molecular genetic findings, and commonly encountered diagnostic issues. These include issues regarding FOXL2 and DICER1 mutational analysis, high grade/anaplastic transformation in granulosa cell tumors, evolving understanding of Sertoli-Leydig cell tumors, and recent insights into the enigmatic gynandroblastoma. Relevant features of Sertoli cell, signet ring, and microcystic stromal tumors are also discussed, along with the unique immunohistochemical and genetic features of select tumors that mimic sex cord-stromal neoplasms. The latter category includes endometrioid carcinomas with sex cord-like morphology which are frequently PAX8-negative, as well as recently described entities defined by specific gene alterations including GLI1, EWSR1/FUS::CREB1/CREM, and STK11.