Objective: To evaluate the effects of hormone replacement therapy (HRT) and oral contraceptives (OCs) on lung cancer risk in women.
Methods: We retrieved studies by systematically searching Medline and other computerized databases. Pooled odds ratios (OR) were appropriately derived from fixed-effects or, in the presence of heterogeneity, random-effects models.
Results: Twelve studies were identified including 3 cohort studies and 9 case-control studies. The OR value associated with HRT was 0.88 (95% CI: 0.77-1.01). Subgroup analyses by smoking revealed that the OR value associated with HRT in smokers' and non-smokers' women were 0.76(95% CI: 0.61-0.95) and 0.78 (95% CI: 0.64-0.95), respectively. There was no statistical relationship between lung cancer risk and OCs (OR = 0.95; 95% CI: 0.83-1.20).
Conclusion: The results suggest a potential decreased risk of female lung cancer might be associated with HRT. Additional well-designed studies are warranted to validate these findings.