Diagnosis and follow-up of simple ovarian cysts detected by ultrasound in postmenopausal women.

OBJECTIVE: To determine the malignancy rate in ultrasound-diagnosed, anechoic, small, simple ovarian cysts in postmenopausal women, and to investigate the natural history of these cysts by ultrasound follow-up.

METHODS: Eighty-three postmenopausal women with small, completely anechoic, thin-walled ovarian cysts (less than 5 cm, mean of orthogonal diameters) were diagnosed at our ultrasound unit during the period 1983-1992. Forty-three underwent surgery; the remaining 40 were offered follow-up ultrasonography as part of the present study, and, of them, five died, two were unavailable because of intercurrent disease, and one moved abroad, leaving 32 to be included in our study.

RESULTS: There were no cases of ovarian cancer in the surgery group. In the nonsurgery (follow-up) group, the time since detection of the lesion ranged from 1-9 years. On follow-up ultrasonography, 12 of the 32 cysts had disappeared and only one had increased in size. According to histopathology records, no ovarian cancer was diagnosed in any of the seven cases in which the patient was not available for reexamination by ultrasound.

CONCLUSION: Nonpalpable ovarian cysts are commonly detected by ultrasound in asymptomatic women, but the risk of malignancy appears to be very low. We recommend ultrasound follow-up of stationary lesions and that surgery be confined to symptomatic cases or those in which there is a family history of ovarian, breast, or colon cancer.