Natural history of sonographically detected simple unilocular adnexal cysts in asymptomatic postmenopausal women.

OBJECTIVE

To determine the natural history of simple unilocular adnexal cysts in asymptomatic postmenopausal women.

METHODS

Eight thousand seven hundred ninety-four asymptomatic postmenopausal women underwent transvaginal ultrasound as part of routine gynecological check-up at our institution between January 1995 and June 2002. All patients in whom a simple unilocular adnexal cyst was found out were offered surgical treatment or conservative follow-up with serial transvaginal ultrasound at 6-month intervals. In all these cases, serum CA-125 levels was determined.

RESULTS

Two hundred twenty-three simple adnexal cysts in 215 women were found out (prevalence: 2.5%). Annual incidence did not change significantly. Sixty-six (30.6%) women were lost after initial diagnosis. One hundred and forty-nine patients with 153 cysts were entered ultimately in the study. Forty-five (30%) underwent surgery (34 after initial diagnosis and 11 during follow-up). A total of 49 cysts were removed. The most frequent histological diagnosis was serous cystadenoma (84%). There was a case of a stage IA ovarian carcinoma (2% of the cysts removed, 0.6% of all the cysts included in the study). One hundred and four patients with 104 cysts underwent conservative follow-up throughout the study period. Forty-six (44%) of these cysts resolved spontaneously (74% of them within 2 years). In 14 (30%) of these women, a new cyst was diagnosed when follow-up went on. In 58 patients, cysts persisted during all study period (median follow-up: 48 months, range: 6-90 months), 69.6% of them remained unchanged, 17.2% increased, and 17.2% decreased. Patients in whom cysts resolved spontaneously had a shorter menopausal time (P=0.001) and tend to be younger (P=0.06). No differences were found regarding cysts' features.

CONCLUSION

The risk of malignancy of simple adnexal cysts in asymptomatic postmenopausal women is low. Almost half of them will resolve spontaneously during follow-up. Most of those that persist remain unchanged. Asymptomatic postmenopausal women having simple adnexal cysts can be managed conservatively with a very reasonable degree of reassurance.