Human papillomavirus infection and risk of breast cancer in Iran: a meta-analysis

Background: Breast cancer is the most common malignancy and a leading cause of death in women. Viruses are known to be the risk factors for breast cancer. This systematic review and meta-analysis aimed to evaluate the association between human papillomavirus (HPV) and the development of breast cancer in Iranian women.Methods: The international databases, including Web of Science, Embase, PubMed, Cochrane, and Scopus, were searched in this study. Furthermore, relevant studies published on the association between HPV and breast cancer were identified using the appropriate keywords. The data were analyzed in Stata software (version 14) using the random-effects model. Results: In total, 18 studies were found eligible to be included in this study. The total sample size was determined at 2466 cases with the mean ages of 47.25 and 39.9 years for experimental and control groups. The overall findings showed a significant relationship between developing breast cancer and HPV infection. The results also revealed that the HPV infection increased the risk of breast cancer in women 5.02 fold more than those without HPV infection (95% CI: 3.46-7.29, I2=65.2%, P=0.003). In addition, the prevalence of HPV infection among women with breast cancer was estimated at 25.66% (95% CI: 17.34-34.95, I2=86%, P=0.000).Conclusion: HPV infections, especially high-risk HPVs, are significantly frequent in breast cancer samples and should be considered an important risk factor for developing breast cancer.