Cancer cervix: Epidemiology and disease burden.

Abstract

Cervical cancer remains a major public health problem, ranking as the fourth most common cause of cancer incidence and mortality in women worldwide. Wide variations in cervical cancer incidence and mortality were observed with highest incidence rates in Sub Saharan Africa and with 85% of deaths occurring in developing regions of the world. Non-existent or inadequate screening in public health care settings and limited access to the standard treatment options explains the large geographic variation in cervical cancer rates. Persistent infection with high-risk Human papillomavirus (HPV) types is the major risk factor for cervical cancer. High parity, long-term use of oral contraceptive pills, tobacco consumption, co-infection with other sexually transmitted agents, lifestyle factors such as multiple sexual partners, younger age at first sexual intercourse, immunosuppression, and diet have been identified as the co-factors most likely to influence the risk of acquisition of HPV infection and its further progress to cervical carcinogenesis. Differential screening rates and changes in epidemiological patterns have contributed to decreasing trends in cervical cancer in some developed regions of the world. Lower rates were also observed in North Africa and the Middle East, which may be attributed to cultural norms and conservative sexual behaviors. Across world regions, HPV prevalence was highest in women younger than 35 years of age, declining to a plateau in middle age and showed significant association between national age standardized incidence rates and corresponding estimates of HPV prevalence. The five most common HPV types in HPV-positive women worldwide were HPV16, HPV18, HPV31, HPV58, and HPV52, representing 50% of all HPV infections with HPV-16 and HPV-18 infections accounting for about 70% of the total infection burden. Tracking changing trends in the cervical cancer epidemiological patterns including HPV genotypes will immensely contribute toward effective prevention and control measures for cervical cancer elimination.