In this case report we describe the treatment of a 95-year-old woman with endometrioid adenocarcinoma. She suffered from cardiovascular comorbidity and did not want surgical treatment. Instead a levonorgestrel-releasing intrauterine device (Mirena) was inserted. She had progression of the tumor but with a minimum of symptoms and side effects. At the final examination there were no signs of extra uterine disease. The levonorgestrel-releasing intrauterine device may be an acceptable alternative to surgery in severely comorbid patients, or if the patient refuses surgical treatment.