Background: Parallel to the rising incidence of malignant melanoma in fair-skinned populations, intensive efforts are currently devoted to identifying risk factors for melanoma in addition to the well-known cutaneous factors and those variables related to UV-exposure.
Objective: Systematic review of published results to elucidate the role of oral contraceptives in the development of malignant melanoma.
Data sources: Literature retrieval systems MEDLINE and CANCERLIT as well as reference lists of already collected studies.
Study selection: All 18 (non-duplicate) case-control studies on the above relationship.
Data extraction: From the published data, study-specific odds ratios (OR) and accompanying confidence intervals (CI) were recalculated. For a quantitative meta-analytical summarisation two different models have been applied: a "fixed effects" (FE) and a "random effects" (RE) model.
Data synthesis: Study-specific ORs ranged from 0.13 up to 1.85; however, the majority of studies (14 of 18) yielded similar ORs within the interval [0.82, 1.15]. The summary ORs estimated from FE- and RE-models were both 0.95 (95% CI: [0.87, 1.04] for the FE-model, [0.87, 1.05] for the RE-model).
Conclusion: The systematic review of case-control studies revealed no evidence for an aetiological role of oral contraceptives in the development of malignant melanoma.
PIP: A systematic review of the research literature was conducted to elucidate the role of oral contraceptives (OCs) in the development of malignant melanoma. The retrieval systems MEDLINE and CANCERLIT identified 18 case-control studies of this relationship and study-specific odds ratios (ORs) were recalculated in the meta-analysis. These ORs ranged from 0.13 to 1.85; however, the majority of studies yielded ORs within the 0.82-1.15 range. The summary ORs estimated from both fixed effects and random effects models were each 0.95; the 95% confidence intervals were 0.87-1.04 and 0.87-1.05, respectively, indicating no association. Separate analyses of the OC-malignant melanoma association by year of study publication, type of case group, source of the control group, and type of exposure ascertainment corroborated this lack of significant effect.