[Epidemiology of apparently benign ovarian cysts]

The incidence of ovarian cysts in the general population is difficult to estimate. Certain cysts are functional and generally not operated, except in case of complications. Others are organic cysts which are usually, but not always operated. Data is available only from surgical series or pathology reports. An analysis of the literature shows that for operated cysts, approximately 75% are organic, 25% are function and 1 to 4% of the supposed benign cysts are found to be malignant. In France, the PMSI database on public and private institutions is available on the net (www.le-pmsi.fr). The number of hospital stays for benign ovarian tumors or ovarian cysts was to the order of 45,000 in 1998 and 1999. Twenty-one percent of these patients were discharged without surgery. Most had a functional cyst of the ovary. This leaves 32,000 women who underwent surgery annually for an ovarian cyst. Nearly 7000 women were hospitalized for follicular or yellow body cysts, i.e. 15%, with an incidence of 29/100,000 women over the age of 15 years. The abstention rate for hospitalized women with a follicular cyst or a yellow body cyst was 30 to 40%. For endometrioma, there were 5218 hospitalizations in 1999 (2137 in the public hospitals and 3081 in private clinics) (11% of the hospitalizations). The rate of abstention was 11% (15% in the public hospitals and 8% in private clinics). Approximately 4100 women thus underwent surgery, including 13% for ovarian cysts. According to data in the literature, serous and mucinous cysts account for 20 to 30% of the operated cysts and dermoid cysts for 10 to 20%. The type of cyst cannot be identified with the international WHO classification used in the PMSI.