Serous endometrial intra-epithelial carcinoma: an observational study

Background Serous endometrial intra-epithelial carcinoma is described as a malignant, superficial spreading lesion with risk of extra-uterine spread at time of diagnosis, and poor outcome. Objective To evaluate the surgical management of patients with serous endometrial intra-epithelial carcinoma and its impact on oncologic outcomes and complications. Methods This Dutch observational retrospective cohort study evaluated all patients diagnosed with pure serous endometrial intra-epithelial carcinoma in the Netherlands, between January 2012 and July 2020. The pathological examination was reviewed by two pathologists with expertise in gynecological oncology. Clinical data were obtained when the diagnosis was confirmed. Primary outcome is progression-free survival, secondary outcomes are duration of follow-up, adverse events related to surgery, and overall survival. Results A total of 23 patients from 13 medical centers were included, of whom 15 (65.2%) presented with post-menopausal blood loss. In 17 patients (73.9%) the intra-epithelial lesion was present in an endometrial polyp. All patients underwent hysterectomy, of whom 12 patients (52.2%) were surgically staged. None of the staged patients showed extra-uterine disease. Two patients received adjuvant brachytherapy. There were no recurrences of disease (median follow-up duration of 35.6 months (range 1.0-108.6) and no disease-related deaths in this cohort. Conclusion In patients with serous endometrial intra-epithelial carcinoma, median progression-free survival reached nearly 3 years and no recurrences have been reported. Our results do not endorse World Health Organization 2014 advice to treat serous endometrial intra-epithelial carcinoma as high-grade, high-risk endometrial carcinoma. Full surgical staging might possibly lead to overtreatment.