Controversies in Gynecologic Cancer Staging: An AJCC Cancer Staging Manual, Eighth Edition Perspective

Staging systems provide a common language to support clinical research and decision making in patients with cancer. The eighth edition of the AJCC Cancer Staging Manual incorporates updates that reflect evolving clinical practices and scientific insights. The present article summarizes changes that have been made for gynecologic subsites and outlines continued challenges. Gynecologic American Joint Committee on Cancer/ International Union Against Cancer staging continues to conform closely to current International Federation of Obstetrics and Gynecology staging. The eighth edition is aligned with the major revision made to International Federation of Obstetrics and Gynecology staging of ovarian cancer in 2014 and contains a unified staging system for ovarian, fallopian tube, and primary peritoneal cancer. Continuing challenges for ovarian cancer include determining the relative significance of intraoperative rupture, surface involvement, and positive washings, which are rank ordered in the new staging system. Another challenge is assignment of a tubal versus ovarian primary site for high-grade serous carcinoma, which cannot be done in a reliable way. In uterine carcinoma, endometrial intraepithelial carcinoma is now recognized as a T1 cancer, and nodal micrometastases have been defined with their own N stage. Also, isolated tumor cells in lymph nodes have been incorporated in the staging of all gynecologic carcinomas. The staging of uterine sarcoma is largely unchanged. Future revisions may consider grouping these tumors with soft tissue sarcomas at large. Staging of cervical cancer is largely unchanged. Nomenclature of early invasive carcinoma and the challenges in defining tumor dimension in cervical carcinoma are discussed. The nodal staging of vulvar cancer now incorporates a vocabulary for isolated tumor cells and micrometastases. Despite the current interest in molecular staging, the eighth edition expert panel did not identify any specific biomarkers for inclusion in stage classification, but several are recommended for collection as ancillary data elements, including p16 status in vulvar, vaginal, and cervical tumors. In the eighth edition, as in the seventh, anatomic factors remain the cornerstone of gynecologic cancer staging.