Molecular Characterizations of Gynecologic Carcinosarcomas: A Focus on the Immune Microenvironment.

Gynecologic carcinosarcomas, specifically of endometrial and ovarian origin, are aggressive and rare tumors. Treatment data are limited and are often extrapolated from other histologies and smaller retrospective studies. While the optimal therapy approach remains contentious, treatment is often multimodal and may include surgery, chemotherapy, radiation, or a combination of multiple strategies. However, despite aggressive treatment, these tumors fare worse than carcinomas of the same anatomic sites irrespective of their stage. Recent studies have described in-depth molecular characterizations of gynecologic carcinosarcomas. Although many molecular features mirror those seen in other uterine and ovarian epithelial tumors, the high prevalence of epithelial-mesenchymal transition is more unique. Recently, molecular descriptions have expanded to begin to characterize the tumor immune microenvironment. While the importance of the immune microenvironment has been well-established for other tumor types, it has been less systematically explored in gynecologic carcinosarcomas. Furthermore, the use of immunotherapy in patients with gynecologic carcinosarcomas has not been extensively evaluated. In this review, we summarize the available data surrounding gynecologic carcinosarcomas, with a focus on the immune microenvironment. We end with a discussion of potential immunotherapy uses and future directions for the field.