Fertility-sparing treatment for low-grade endometrial stromal sarcoma: a retrospective cohort study

Background: Little is known about the oncologic results of patients with low-grade endometrial stromal sarcoma (LGESS) with fertility preservation. This study was to investigate the prognosis of fertility-sparing surgeries and relevant obstetrical outcomes. Methods: All eligible patients in the study center were retrospectively reviewed if they consented to surgical treatment for primary LGESS from February 2012 to June 2019 in the study center. Follow-up of fertility and oncologic outcomes was carried out until June 1, 2020. Results: Among 135 patients accepted surgical therapy for primary uterine LGESS, 21 (15.6%) and 42 (31.1%) had fertility-sparing surgery and ovarian preservation, respectively. After a median follow-up of 38.5 (range 5-98) months, differences existed in the recurrent rates among patients with and without fertility-sparing surgery (47.6% versus 15.8%, p =0.002), or with and without ovarian preservation (42.9% versus 10.8%, p <0.001). Fertility-sparing surgery and ovarian preservation significantly increased the recurrent risks in the whole cohort (hazard ratio [HR] 3.5 and 5.2, 95% confidential interval [CI] 1.6-7.6 and 2.4-11.3, p =0.002 and <0.001) and in stage I patients (HR 2.6 and 3.1, 95% CI 1.0-6.4 and 1.3-7.4, p =0.041 and 0.011). No factor was found to be associated with increased mortality risk. Among 9 patients attempting pregnancy, 7 (77.8%) achieved 8 live births. Three advanced stage patients with fertility-sparing surgery all experienced recurrence without successful conception. Conclusion: Fertility-sparing surgery for LGESS results in a significantly increased risk of recurrence but not of mortality, and has promising results in terms of live births in stage I patients.