Low-grade endometrial stromal sarcoma arising from extrauterine deep infiltrating endometriosis: a rare, but important differential diagnosis and short review of the literature.

Background: Low-grade endometrial stroma sarcoma is a very rare mesenchymal neoplasm, that is usually found inside the uterine corpus. It is very uncommon that LG-ESS arises from extrauterine foci. Case presentation: We report the case of a 31-year-old patient diagnosed with extrauterine LG-ESS arising from deep infiltrating endometriosis. Primary symptoms, diagnostic workflow, operating method, and the outcome will be described, as well as a short review of the current literature about the optimal treatment for young LG-ESS patients within the reproductive window. Conclusions: Long-term surveillance is imperative for patients with LG-ESS given the potential for late recurrences. Although extrauterine LG-ESS represents an exceedingly rare gynecologic malignancy, establishing standardized treatment approaches is critical to optimize therapeutic efficacy and improve patient outcomes.