Tobacco smoke is a well-established human papillomavirus (HPV) cofactor for the development of cervical pre-cancer and cancer, but the molecular mechanisms by which smoking increases the risk of cervical cancer remain unknown. Some 19 kinds of HPV have been linked to cervical cancer; HPV-16 is the most deadly. Benzo[a]pyrene (BaP), is a major carcinogen in cigarette smoke, that may interact with HPV.
HPV or Human Papilloma Virus is the name for a group of viruses that affect your skin and the moist membranes lining your body, for example, in your cervix, anus, mouth and throat. |
Researchers Anthony S. Gunnell and his colleagues at Sweden’s Karolinska Institute suspected smoking and HPV-16 might work together. So they compared the medical records of 375 women who had the earliest stage of cervical cancer to the records of 363 women with similar characteristics who did not have the cancer. Based on Pap smear taken an average of nine years before the women developed cervical cancer, the researchers were able to tell whether the women had had an HPV-16 infection. They also were able to see whether the women had had high or low levels of HPV in their blood — something doctors call high or low viral load.
The results:
- Among smokers, those who had tested positive for HPV-16 were 14.4 times more likely to get cervical cancer than those who did not have the infection.
- Among smokers, those who had had high HPV-16 viral load were 27 times more likely to get cervical cancer than those who did not have the infection.
- However, among nonsmokers, those who had tested positive for HPV-16 were only six times more likely to get cervical cancer than nonsmokers who did not have the infection. Having high vs. low HPV-16 viral load did not affect that statistic.
- Women who had continued to smoke further multiplied their chances of getting cervical cancer.
The researchers suggest smoking may help HPV-16 grow faster — possibly by slowing helpful immune responses. They also suggest smoking may speed the process by which HPV-16 causes cancer.
Smoking increases the risk of cervical cancer!
Numerous recent studies have found abundant evidence of the link between smoking and cervical cancer.
- Current smokers are at significantly increased risk of developing cervical cancer when compared to never smokers.
- Risk increases with the number of cigarettes smoked per day.
- Risk increases the earlier you start smoking.
- Risk increases with age at diagnosis of the cancer
- Past smokers have a lower risk for cervical cancer than current smokers.
- Smoking poorly impacts survival in women with cervical cancer.
Link between smoking and HPV
- Smoking increases your risk of being infected with a high-risk HPV infection.
- For a woman with a high-risk HPV infection, smoking increases the risk of developing a cervical precancerous lesion.
- Smokers keep HPV cervical infections longer and are less likely to clear them, when compared to women who have never smoked.
A study performed in Washington showed that after two years, women who quit smoking had the same risk of cervical cancer as women who never smoked. The same study showed that women with active cervical cancer during the screening period were more likely to be those who smoked at least 10 cigarettes a day than nonsmokers.
Women who have HPV should not smoke or should cut down on how much they smoke if they want to reduce their cancer risk.
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