IVF impact on the risk of recurrence of endometrial adenocarcinoma after fertility-sparing management.

RESEARCH QUESTION: Do IVF treatments after conservative management of endometrial atypical hyperplasia or grade 1 endometrial adenocarcinoma (AH/EC) increase the risk of disease recurrence? DESIGN: This is a prospective cohort study from a national registry from January 2008 to July 2019. Sixty patients had an AH/EC and received progestin treatment using chlormadinone acetate for at least 3 months. After remission, 31 patients underwent IVF and 29 did not. The primary outcome was the recurrence rate at 24 months according to the use of IVF. The secondary outcome was the identification of risk factors for recurrence. RESULTS: The probability of 2-year recurrence was 37.7% (SD 10.41%) in the IVF group and 55.7% (SD 14.02%) in the no IVF group (P = 0.13). Obesity, nulliparity, polycystic ovary syndrome, age and tumoural characteristics were not associated with recurrence. Pregnancy was a protective factor for recurrence, with 2-year recurrence probabilities of 20.5% and 62.0% in the pregnancy and no pregnancy groups, respectively (P = 0.002, 95% CI 0.06-0.61). In contrast, the number of cycles, maximum serum oestradiol concentration during ovarian stimulation, ovarian stimulation protocol, total dose of gonadotrophin administered and thickness of the endometrium showed no significant differences in terms of the risk of recurrence in the IVF subgroup. CONCLUSION: IVF treatment after fertility-sparing management of AH/EC does not increase the risk of recurrence. Therefore, it is an acceptable strategy to decrease the time to pregnancy. Overall, the recurrence rate is high enough to justify close monitoring once remission occurs.