Endometriosis-Associated Neoplasms: A Review of Clinicopathologic Features and Common Diagnostic Challenges

Context.—: Neoplastic potential of endometriosis is well established, albeit rare, and endometriosis-associated neoplasms are frequently encountered in clinical practice. Objective.—: To summarize and review common diagnostic issues with endometriosis and endometriosis-associated neoplasms, as well as review clinical, pathologic, and molecular characteristics of these tumors and discuss differential diagnoses. Data Sources.—: Literature review and cases from the authors' personal practice. Conclusions.—: Endometriosis-associated neoplasms are a frequently encountered heterogeneous group of ovarian neoplasms with some unifying features, including younger age and lower stage at presentation. The most common tumors are endometrioid carcinomas, clear cell carcinomas, and seromucinous borderline tumors. The diverse morphologic features and variant histologic patterns can significantly complicate interpretation and compromise reproducibility. This review offers a systematic approach in overcoming these diagnostic challenges that are facilitated by the integration of histologic, immunohistochemical, and molecular findings.