Is it possible for a virus to cause cancer? Can there be any link between human papilloma virus or HPV and cervical cancer, or is it just another myth associated with cancer! Here are the facts:
More than 90% of patients with cervical cancer show the presence of HPV DNA in the affected cells.
Does it mean that any woman who acquires HPV infection will have cervical cancer? Before reaching any conclusion, some more facts should be known:
Human Papilloma Virus (HPV) and Its Types
HPV or human papilloma virus has more than 70 sub types, most of which have an affinity for the genital epithelium. These sub types have been divided into three categories, depending on their ability to produce malignant changes in the cells:
1. Low risk HPV types
- These include the types 6, 11, 42, 43 and 44
- Mostly associated with genital warts and the early stages of cervical intra-epithelial neoplasia or CIN, which is the precursor of cervical cancer
2. Intermediate risk HPV types
- Types 33, 35, 51 and 52
- Found in advanced cases of CIN
3. High risk HPV types
- Types 16, 18, 31, 39, 45, 56, 58, 59 and 68
- Found in advanced cases of CIN and invasive cervical cancer
- HPV 16 is mostly associated with squamous cell carcinoma
- HPV 18 is mostly associated with adenocarcinoma
HPV Infection Alone Can Not Be Responsible for Cervical Cancer: Why?
HPV infection is very common among women and only a small percentage of infected women develop cancer of cervix:
- About 40% women in their twenties, harbour HPV in the genital epithelium.
- In about 90% of infected women with normal immunity, the infection resolves spontaneously and does not produce cancer.
- So, HPV alone cannot be responsible for cervical cancer.
- Other risk factors, which work with HPV to produce cancer of cervix are immunosuppression due to HIV or other sexually transmitted diseases, cigarette smoking, multiple births at short intervals or the prolonged use of oral contraceptive pills.
What Happens When a Woman Becomes Infected With HPV?
If a woman acquires HPV infection, there are three possibilities:
1. HPV may exist in a latent form, without producing any changes.
2. The virus may undergo replication, leading to active infection.
3. In presence of other risk factors for cervical cancer, the DNA of HPV may unite with the human genome, resulting in malignant changes.
Conclusion
Though most of the women infected with HPV will not develop cervical cancer; however, in presence of additional risk factors, like immunosuppression, HPV does attack the human genome to produce cancer. So, link between HPV and cervical cancer definitely exists, but the presence of other risk factors is also necessary for the malignant changes to take place.
Also read:
Early Detection Of Cervical Cancer - Identify The Warning Signs
14 Risk Factors For Cervical Cancer
