Fertility-preserving treatment with progestin, and pathological criteria to predict responses, in young women with endometrial cancer

There are therapeutic dilemmas regarding conservative management of endometrial cancer in young women. We planned a prospective study to conservatively treat women aged under 40 years with clinical stage 1A, grade 1 endometrioid adenocarcinoma from 1999 to 2005. There were nine women (aged 28–40) who fulfilled the criteria, and medroxyprogesterone acetate (400 mg/day) was continued for 6 months. Curettage materials were pathologically evaluated according to our criteria including partial response (PR) (a small amount of cancer tissue with remarkable hormonal effects or atypical hyperplasia). To predict complete response (CR) to progestin, immunohistochemical staining for insulin-like growth factor type 1 receptor, phosphatase and tensin homolog deleted on chromosome ten, progesterone receptor (PgR), estrogen receptor and Ki67 were assessed. Seven (78%) and two cases presented complete and PRs, respectively. Two patients developed recurrent disease 10 and 22 months after the last dilatation and curettage, and both had synchronous ovarian cancer. However, all nine patients were alive and disease-free for a mean of 39 months. Of eight married patients, four (50%) conceived and three delivered full-term singletons. CR was related to positive expression of PgR ( P = 0.008). Patients with an initial PR can obtain CR after further treatment, and the PgR may be useful in predicting CR to fertility-preserving treatment in young women with endometrial cancer.