Endometriosis Linked to Higher Risk of Melanoma, but Not Other Skin Cancers, Study Suggests

Endometriosis Linked to Higher Risk of Melanoma, but Not Other Skin Cancers, Study Suggests

Women with a history of endometriosis may have an increased risk of developing melanoma, but no association was seen in other skin cancers, according to the results of a large prospective analysis.

The study, “Endometriosis and the risk of skin cancer: a prospective cohort study,” was published in the journal Cancer, Causes & Control.

Recent studies have suggested that women with a history of endometriosis may have a higher risk for skin cancer. But in the majority of these studies, the data was collected retrospectively, or the number of participants was rather small. Taken together, both conditions could have introduced some bias in the analysis.

Skin cancers are classified according to two major types: the non-melanoma skin cancers (NMSCs) and cutaneous melanoma, the most dangerous form due to its high potential for metastasis. How endometriosis was correlated particularly with the NMSCs had not been thoroughly researched.

The authors performed a prospective analysis to investigate the link between endometriosis and the risk of non-melanoma and melanoma skin cancers.

They analyzed data from the 1990 E3N study, which enrolled 98,995 French women born from 1925 to 1950. The participants were asked to answer a self-administered questionnaire on their lifestyle and medical history at the time of enrollment and follow-up questionnaires sent every two to three years thereafter.

During these periods, all the cases of surgically confirmed endometriosis and skin cancer diagnoses were collected and registered. A pathologist confirmed the skin cancers.

During 18 years, from 1990 to 2008, a total number of 535 cases of melanoma were confirmed, along with 247 squamous-cell carcinomas and 1,712 basal-cell carcinomas, the two forms of NMSCs.

The prospective analysis showed that a history of endometriosis was associated with a higher skin cancer risk, specifically in melanoma, confirming the results of previous studies. No association was observed between endometriosis and squamous-cell carcinoma or basal-cell carcinoma.

“For NMSCs, associations with endometriosis were restricted to BCC among never-users of pre-menopausal progestogens,” researchers wrote. They also found that women with a family history of skin cancer had a higher risk for endometriosis.

Overall, “in the largest and most comprehensive analysis of endometriosis and skin cancer to date, our data support an association between a personal history of endometriosis and skin cancer risk and suggests that the association is most robust for cutaneous melanoma,” the study concluded.