Background With hysteroscopy, concerns have surfaced regarding intraperitoneal spread of endometrial cancer (EC); no studies have evaluated the effect of hysteroscopy on the disease course of a large series of patients with exclusively high risk histology.

Methods Patients who underwent hysterectomy for grade 3 EC at Mayo Clinic in Rochester, MN between January 2009-June 2016 were included, noting hysteroscopy within 6 months. Follow-up was restricted to five years. Cox proportional hazards models were fit to evaluate associations between hysteroscopy exposure and progression.

Results Among 831 patients, 133 underwent hysteroscopy. Patients with versus without hysteroscopy did not differ in mean age (67.7 vs. 67.8 years), BMI (31.6 vs. 31.3 kg/m2), ASA ≥3 (35.3% vs. 38.3%), or serous histology (47.4% vs. 48.7%). Advanced disease (III/IV) was less common among hysteroscopy patients (30.1% vs 43.8%, p=0.003). No difference was observed between those with hysteroscopy versus without (all p>0.05) in positive cytology (22.0% [26/118] vs. 29.7% [191/643]), stage IV disease (16.5% [22/133] vs. 21.9% [153/698]), any positive cytology OR adnexal invasion OR stage IV (28.6% [38/133] vs. 36.1% [252/698]), the aforementioned OR peritoneal recurrence within 2 years (30.8% [41/133] vs. 39.3% [274/698]). After stratifying by stage, hysteroscopy did not increase risk of progression (HR 1.06, 95% CI 0.59–1.92 for stage I/II; HR 0.96, 95% CI 0.62–1.48 for stage III/IV).

Conclusion In this retrospective study of high grade EC, we did not observe any significant association between pre-operative hysteroscopy EC and incidence of positive cytology, peritoneal disease, or progression.