NEW YORK (Reuters Health) – In women over 55, simple ovarian cysts are common, usually resolving or persisting without progression, according to data from the prospective Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO).
The presence of simple cysts, often found incidentally during transvaginal ultrasound (TVU) exams, did not affect the risk of ovarian cancer, according to lead author Dr. Robert T. Greenlee and colleagues — bolstering recent recommendations that unilocular simple cysts in postmenopausal women be followed without intervention.
Dr. Greenlee, from the Marshfield Clinic Research Foundation, Wisconsin, and associates followed 15,735 postmenopausal women through 4 years of annual TVU screening. All were between 55 and 74 years old at enrollment, and all had CA-125 measurements and TVU studies at baseline. Both tests were repeated annually. In addition, for a woman to be included in the study, both ovaries had to be visualized at least once by TVU.
Simple cysts were defined as having a volume < 10 cm3 and with no solid areas, septae, or papillary projections within the cyst cavity.
In a paper published online January 25 in the American Journal of Obstetrics and Gynecology, the investigators report that the prevalence of at least 1 simple cyst detected during the first fully visualized TVU screening was 14.1%. Potential correlates of prevalent simple cysts were younger age (55 to 59), education past high school, and early menopause. The odds were also higher in women with a history of benign ovarian cysts, menopause before age 40, and a first pregnancy at or beyond age 30.
Among women without a cyst of any kind on their first fully visualized TVU screening, the incidence of simple cysts was approximately 8% per year, remained fairly constant, and did not vary by age.
One-third of ovaries with simple cysts were cyst-free the following year. Even when 2 or more cysts were present, all resolved a quarter of the time. Only 6% progressed in complexity from 1 year to the next.
Women with and without simple cysts were at similar risk of invasive ovarian cancer after nearly 8 years of follow-up evaluation, the authors write. Furthermore, traditional ovarian cancer risk factors, such as increasing age, family history of breast or ovarian cancer, nulliparity, and infertility, were not associated with simple cysts. Finally, changes in average CA-125 were not correlated with increases in the number or progression of simple cysts.
Thus, Dr. Greenlee and his group conclude,