21 May 2012:
The prevalence of simple ovarian cysts in postmenopausal women may range from 3% to 15%. Simple cysts are usually followed conservatively, but concern about progression to malignancy may lead to surgical exploration, which in most cases would likely be for benign conditions. A recent retrospective study from the USA  evaluated 619 patients with 743 simple ovarian cysts; 305 patients (49.27%) were lost in follow-up. Therefore, 314 patients (50.73%) with 378 cysts were followed further by ultrasound study. In all, 175 (46.30%) of the 378 cysts that could be followed further had spontaneous resolution and 166 cysts (43.91%) persisted unchanged over the follow-up period. Thirty cysts (7.94%) turned into complex cysts and four cysts (1.06%) significantly increased in size. One cyst significantly decreased in size, although it did not resolve. Only one patient developed papillary serous carcinoma (high grade) of the ovary. This occurred 3 years after her last ultrasound for simple cyst surveillance. Thus, simple ovarian cysts during the menopause can be followed conservatively because their risk for malignant transformation is low. The majority of these cysts either resolve spontaneously or persist unaltered on follow-up.