Efficacy of fertility-sparing treatment with LNG-IUS is associated with different ProMisE subtypes of endometrial carcinoma or atypical endometrial hyperplasia.

objectiveTo determine whether proactive molecular risk classifier for endometrial cancer (ProMisE) could be used to assess the prognosis of patients with atypical endometrial hyperplasia (AEH) or early-stage endometrial cancer (EC) treated with levonorgestrel-releasing intrauterine system (LNG-IUS).

methodsA retrospective cohort study was conducted among 93 AEH or early-stage EC patients who received LNG-IUS to preserve fertility . By immunohistochemistry and gene sequencing, 4 subtypes of ProMisE were identified (p53 wild type [p53 wt], mismatch repair-deficient [MMRd], p53-abnormal, and POLE-mutated). The primary outcome was the time to complete response (CR) after LNG-IUS therapy. Secondary outcomes included the recurrence rate after CR and success rate of conception.

resultsAmong the 93 patients, 15 (16.1%) were classified as MMRd, 6 (6.5%) as POLE-mutated, 5 (5.4%) as p53-abnormal, and 67 (72.0%) as p53 wt. Comparison of serum cancer antigen 125, family history of tumor, and positive rates of programmed cell death 1 ligand 1 protein and Ki67 protein in 4 groups showed statistically significant differences (p<0.05). Patients with the p53-abnormal subtype had the lowest overall CR rate (40%) and the highest recurrence rate (2/2). Patients with POLE-mutated subtype had the best prognosis, and all 6 patients achieved CR. When patients achieved complete remission, assisted reproductive technology was more likely to help them conceive than natural conception (p<0.05).

conclusionPatients with early-stage EC or AEH who are more likely to benefit from fertility-sparing treatment can be identified using ProMisE classifier. Patients with POLE-mutated are suitable for fertility-sparing treatment with LNG-IUS.