Cervical cancer is undisputedly linked to one or two subtypes of human papilloma viruses (HPV-18 or HPV-16). However, infections of human herpes virus-2 (HSV-2) and the bacterium Chlamydia or behaviors such as smoking, drug use or promiscuous sex life play accessory roles in the development cervical cancer.
Early reports, up until about 2002, suggested that HSV-2 or Chlamydia caused cervical cancer because so many women who developed the disease were infected with either or both of these pathogens. Now it appears that such sexually transmitted infections, if they have an impact at all, may be indirectly important by causing inflammation in cervical cells and nudging them toward developing cancer when HPV is already present.
Smoking, drug addiction and oral contraceptive use are other risk factors that have been previously linked to cervical cancer. However, a 2008 report from researchers at Turku University Hospital in Finland looked at nearly 2,000 women from Latin America and Eastern Europe and found that smoking or drug use themselves did not increase the risk for early or late stage cervical cancer. Use of contraceptives was also not a direct factor.
Instead, the authors suggest that these activities seem to be closely associated with more risky sexual behaviors such as having multiple partners, which in turn, increases the chances of contracting cancer-causing stains of HPV, the real cause of cervical cancer.
The Finnish authors state that their results “have significantly contributed to solving several of the open issues in the natural history of high risk HPV infections, including their risk factors.”
These findings emphasize the importance for women to get regular testing for HPV along with their conventional Pap smears. “Screening for cervical cancer precursors will be mandatory until the foreseeable future,” the researchers write, “even in this era of HPV vaccination.”
Almonte, M., et al., 2008. “Risk factors for human papillomavirus exposure and co-factors for cervical cancer in Latin America and the Caribbean” Vaccine.