Chlamydia Trachomatis Infection-Associated Risk of Cervical Cancer: A Meta-Analysis

As whether Chlamydia trachomatis infection increases the risk of cervical cancer is controversial in the literature, we performed a meta-analysis. Based on a comprehensive search of publications in the Medline, Cochrane, and EMBASE databases, we identified and extracted data from all relevant articles examining C. trachomatis infection and the risk of cervical cancer. The quality of each included study was assessed according to the 9-star Newcastle–Ottawa scale. The strength of association between the C. trachomatis and risk of cervical cancer was estimated by odds ratio (OR) and 95% confidence intervals (CIs). This review was registered at PROSPERO with registration No. CRD42014015672. A total of 22 studies with 4291 cervical cancer cases and 7628 controls were identified. Overall, C. trachomatis was significantly linked to increased cervical cancer risk in prospective studies (OR = 2.21, 95% CI: 1.88–2.61, P < 0.001), as well as in retrospective studies (OR = 2.19, 95% CI: 1.74–2.74, P < 0.001). Additionally, with a multivariate logistic regression analysis adjusted for HPV and age, C. trachomatis infection was identified as an independent predictor of cervical cancer in 11 studies (OR = 1.76, 95% CI: 1.03–3.01, P = 0.04). Coinfection of human papilloma virus and C. trachomatis has a higher risk of cervical cancer (OR = 4.03, 95% CI: 3.15–5.16, P < 0.001). A subgroup analysis based on histological type indicated an elevated risk for both squamous cell carcinoma (OR = 2.21, 95% CI: 2.00–2.45, P < 0.001), and adenocarcinoma (OR = 1.61, 95% CI: 1.21–2.15, P = 0.001), in associated with C. trachomatis. Subgroup analysis by where C. trachomatis infection was detected showed a significantly higher risk of cervical cancer associated with C. trachomatis infection detected in serum (OR = 2.20, 95% CI: 2.01–2.42, P < 0.001), cervical tissue blocks (OR = 2.88, 95% CI: 1.21–6.83, P = 0.02), and cervical secretion (OR = 2.71, 95% CI: 1.41–5.20, P = 0.003), especially in serum with no obvious heterogeneity. In conclusion, our novel data demonstrate that individuals infected with C. trachomatis have a higher risk of cervical cancer. Therefore, it is necessary to expand C. trachomatis infection screening and treat women with C. trachomatis promptly, particularly those with human papilloma virus infections. This approach will not only protect against pelvic inflammatory disease and infertility, but may also prevent cervical cancer.