Objective: The rate of lung cancer in female patients is increasing, with different features from male patients being displayed. Hormonal factors could play a role. The association between the development of uterine myoma (UM) and female hormones has also been reported. The relationship between female lung cancer and UM may be due to the effect of female hormones.
Methods: Data from 50 711 Taiwanese women with UM were retrieved from the National Health Insurance Research Database between 2000 and 2012. They were propensity-score matched with 50 711 women without UM (control group). A multivariate Cox proportional hazard regression model was used to compare the incidence of lung cancer between groups and to determine the hazard ratio of lung cancer in the UM group.
Results: The risk of lung cancer was significantly higher in women with myoma (adjusted hazard ratio: 1.62, 95% confidence ratio = 1.24-2.12). Stratified analyses demonstrated that the significantly increased risk of lung cancer was more likely to be found in certain groups, such as women who (a) are of younger age, (b) have a mid-level income, (c) have the highest urbanisation level, (d) are office workers and (e) with a longer follow-up period of myoma. Furthermore, myomectomy did not affect the risk pattern.
Conclusion: The results from this nationwide population-based cohort study suggested that UM is associated with a higher risk of developing lung cancer. However, the exact underlying mechanism accounted for this remains unclear, and our findings still need to be verified by further comprehensive studies elsewhere.
© 2021 John Wiley & Sons Ltd.