The prognostic and therapeutic implications of cytologic atypia in patients with endometrial hyperplasia.

From 1970 to 1992, 136 patients with a histologic diagnosis of endometrial hyperplasia underwent total abdominal hysterectomy at the University of Kentucky Medical Center. Slides of the curettage or biopsy specimens were reviewed and classified according to the International Society of Gynecologic Pathologists System as simple or complex endometrial hyperplasia with or without cytologic atypia. Slides of the hysterectomy specimens were likewise reviewed independently and classified according to the same system. Eighty-two patients had a preoperative diagnosis of simple or complex endometrial hyperplasia without atypia. There were no cases of occult endometrial carcinoma in the hysterectomy specimens of these patients. Simple or complex hyperplasia with atypia was present in 54 patients and endometrial adenocarcinoma was observed in 19 of these cases (35%). The International Federation of Gynecology and Obstetrics stage and histologic grade of these patients was as follows: Stage IA grade 1--5; Stage IB grade 1--10; Stage IB grade 2--1; Stage IC grade 1--1; Stage IC grade 2--1; and Stage IIIA grade 2--1. The risk of associated endometrial cancer in patients with atypical hyperplasia was independent of age, diabetes mellitus, hypertension, or the use of exogenous estrogens. All patients with endometrial cancer have been followed for 1-12 years (mean 3.0 years) after therapy and no patient has experienced tumor recurrence. These data suggest that there is a significant risk of endometrial cancer in patients with histologic evidence of atypical endometrial hyperplasia on curettage or biopsy. At the time of surgery, patients with atypical endometrial hyperplasia should have careful inspection of the uterine specimen. Any endometrial tissue suspicious for malignancy should be examined histologically, and if cancer is confirmed, complete surgical staging should be performed.