Fertility sparing treatment of complex atypical hyperplasia and low grade endometrial cancer using oral progestin

•Our CAH or G1EC patients < 45 y had a 55% complete response rate to oral progestin.•Increasing age was associated with a lower likelihood of complete response.•The benefit of continuing progestin > 1 y in the absence of a histologic response may be limited.

ObjectiveOral progestin is an alternative to hysterectomy for women with complex atypical hyperplasia (CAH) or grade one endometrial cancer (G1EC) who wish fertility preservation. We evaluated treatment efficacy and fertility outcomes in this population.MethodsWomen < 45 y treated with oral progestin for CAH or G1EC were identified from two cancer centers. Data were obtained from medical records and telephone questionnaires. Time until complete response (CR), and from CR until recurrence was censored for patients without events and analyzed for associations with patient and treatment characteristics; cumulative incidence functions were used to estimate event probability over time.Results44 patients were identified, 19 (43%) with CAH and 25 (57%) with G1EC. Median age was 36.5 y (26-44). 24 (55%) achieved CR (median time: 5.7 months). Older age was associated with a lower likelihood of CR (HR 0.84, p = 0.0003, 95% CI, 0.8-0.9). CR probability appeared to plateau after 12 months of therapy. Among those with CR, 13 (54%) recurred (median time 3.5 y). 24 patients (55%) underwent hysterectomy; 3 (13%) were upstaged. 11 (25%) underwent fertility treatment with the following outcomes: 6 (55%) no pregnancy, 2 (18%) at least one live infant, and 3 (27%) spontaneous abortion. One achieved a live birth without intervention.ConclusionOral progestin is an effective temporizing fertility-sparing treatment for women with CAH/G1EC. Fertility specialist involvement is recommended due to the low live birth rate without intervention. Progestin therapy should be re-evaluated at 1 year in non-responders due to a low probability of success. Hysterectomy is recommended after childbearing due to a high recurrence rate.