Unraveling the controversy: exploring the link between sex hormones and skin cancers through a meta-analysis and systematic review.

Oral contraceptive use was associated with a higher incidence of cutaneous melanoma.

• OR 1.08, 95% CI 1.03-1.13, p < 0.01
• 42 eligible studies were identified for meta-analysis from a search yielding 1016 articles across PubMed, Embase, and Web of Science
• Data searched until July 3, 2024
• Relative risk, odds ratios, and hazard ratios with 95% CIs were synthesized after adjusting

Oral contraceptive use was positively associated with a higher incidence of squamous cell carcinoma.

• OR 1.37, 95% CI 1.15-1.63, p < 0.01
• This was described as a 'positively related statistic difference' for SCC
• Data extracted included study methods, demographics, and reproductive factors

Hormone replacement therapy was associated with a higher incidence of cutaneous melanoma.

• OR 1.18, 95% CI 1.13-1.24, p < 0.01
• This represented the strongest association observed for CM across hormone exposures examined
• Eligible trials confirmed diagnoses and collected hormone use information

Hormone replacement therapy was associated with increased incidence of non-melanoma skin cancer.

• OR 1.13, 95% CI 1.03-1.24, p = 0.01
• Non-melanoma skin cancer (NMSC) was examined as a secondary outcome alongside cutaneous melanoma
• Primary outcomes included both cutaneous melanoma and non-cutaneous melanoma incidence

Menopausal hormone therapy was associated with an increased incidence of cutaneous melanoma.

• OR 1.09, 95% CI 1.00-1.18, p < 0.05
• The confidence interval lower bound of 1.00 indicates a borderline statistically significant association
• MHT was analyzed separately from HRT in the meta-analysis

Age at first birth greater than 30 years was positively correlated with increased incidence of cutaneous melanoma.

• OR 1.21, 95% CI 1.00-1.46, p = 0.05
• Reproductive factors including age at first birth were extracted as part of the data synthesis
• The confidence interval lower bound of 1.00 indicates a borderline statistically significant association

In women whose menopause age was older than 50 years, gradually decreasing endogenous sex hormones were associated with higher risks of skin cancers.

• Endogenous sex hormones were considered alongside exogenous hormone exposures
• Menopause age older than 50 years was identified as a factor associated with increased skin cancer risk
• This finding relates to the gradual decrease of endogenous sex hormones during menopause

The systematic review and meta-analysis identified 42 eligible studies from an initial search yield of 1016 articles.

• Databases searched included PubMed, Embase, and Web of Science (WOS)
• Search was conducted until July 3, 2024
• Skin cancers examined included cutaneous melanoma, basal cell carcinoma, and squamous cell carcinoma
• Trial registration number: CRD42024517445