Low-grade endometrial stromal sarcoma treated with the aromatase inhibitor letrozole

Low-grade endometrial stromal sarcoma is an indolent steroid responsive tumor. Successful hormonal treatment, most commonly with megestrol acetate, has been reported.

A 76-year-old woman underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy 25 years earlier allegedly for a benign condition. She presented to us with postrenal kidney failure and a huge pelvic mass compressing both ureters. After transvaginal trough-cut biopsy of the mass, the diagnosis of low-grade endometrial stromal sarcoma with a high expression of alpha-estrogen receptor was made. The patient was treated with letrozole only with a spectacular response.

To the best of our knowledge, this is the first case for which letrozole was used on long-term basis as first-line hormonal treatment for a recurrent low-grade stromal sarcoma.