Personal History of Endometriosis and Risk of Cutaneous Melanoma in a Large Prospective Cohort of French Women

Background:

An association between melanoma and endometriosis

has been reported, but most findings relied

on case-control studies or a limited number of melanoma

cases, and therefore the available evidence is weak.

Moreover, the effect of other benign gynecological diseases

on melanoma risk is unknown.

Methods:

We prospectively studied data from the Etude

Epide´miologique auprès de femmes de la Mutuelle Ge´ne

´rale de l’EducationNationale cohort, which includes 98 995

French women, insured by a national health scheme mostly

covering teachers, aged 40 to 65 years at inclusion. Data

on history of endometriosis and other benign gynecological

diseases were regularly collected, starting in 1990. Relative

risks and95%confidence intervals were computed using

Cox proportional hazards regression models.

Results:

During 12 years of follow-up, 363 melanoma cases were ascertained among 91 965 subjects. A history of endometriosis (n=5949) was significantly associated with a higher risk of melanoma (relative risk, 1.62; 95% confidence interval, 1.15-2.29). There was also a significantly increased risk among women with a history of fibroma (n=24 375), compared with those who had no such history (relative risk, 1.33; 95% confidence interval, 1.06-1.67). A history of ovarian cyst, uterine polyp, breast adenoma/fibroadenoma, or breast fibrocystic disease was not significantly associated with risk.

Conclusions:

These data provide the strongest evidence to date of a positive association between a history of endometriosis and melanoma risk. The association between

fibroma and melanoma, which has not been previously described, warrants further investigation.