Good advice is welcome at any time, specially when it comes to getting screened for cancer. Because the earlier it is detected, the more successfully it can be arrested. For example, stage 1 breast cancer and cervical cancer among women has a survival rate of more than 90 per cent while in stage 3 it is about 50 per cent. In the case of ovarian cancer, stage 1 has 80 per cent survival rate whereas stage 3 has a survival rate of less than 20 per cent.
Cervical cancer is most common cancer among Indian women with 1.32 lakh new cases and 70,000 deaths every year. The risk factors for cervical cancer in India include multiple sexual partners, early sexual debut and male factors, whereas religion, literacy rate and number of pregnancies do not seem to have a major bearing on cancer risk. However, smoking and other sexually transmitted infections increase the risk of development of cervical cancer.
Screening for cervical cancer in an organised manner has been shown to reduce its incidence in the West to less than one per cent. HPV infection is seen to be highest in the third decade of life, and is found in 75-85 per cent of precancerous lesion and over 99 per cent of cervical cancers. The virus is transmitted through sexual contact and current estimates suggest that 50 per cent of sexually active women have been infected with one or more types of HPV. A causal link between HPV infection and cervical cancer are well established. There is enough evidence, which demonstrates beyond doubt that HPV infection is the first necessary cause of cervical cancer.
South Asia prevalence of HPV-16 infection is seen among over 50 per cent women and for HPV-18 it is 25 per cent. Prevalence of HPV infection is greatest (approximately 20 per cent) among women aged less than 25 years and this virus can be acquired by mere skin-to-skin contact. Therefore anyone who has a normal sex life is at risk of exposure to high-risk HPV types. Condoms reduce the risk but are not fully effective.
For every million women infected with high-risk HPV, 100,000 will develop cervical cytological abnormality on pap smear, 8,000 will develop precancerous lesion and 1,600 will develop invasive cervical cancer. Most people are exposed to high-risk HPV infections at some point. It is seen that the progressive development of cervical cancer from HPV infection takes place over 10 years period, though in few cases it could take place in just 1-2 years.
Cervical Cancer in India
The incidence of cervical cancer in India is 27 per cent of the worldwide total or 125,952 cases. Mortality is 70,528 deaths per year or 30 per cent of the global total. HPV positivity is seen in 99.4 per cent in cervical cancer specimens from Chennai. The overall 5 year survival rate for cervical cancer is 40 per cent, this rate is influenced by clinical stage and treatment mode.
The ?pap smear? is a cytology test that screens for cervical cancer and acts as a secondary prevention mechanism. However, a large number of individual women will develop cervical cancer despite the screening programme due to presence of big cervical erosion. Due to lack of health check ups and majority of women still having home deliveries and totally unaware, incidences of cervical cancer are still extremely high among Indian women.
The incidence of cervical cancer is increasing across the globe specially due to lack of screening facilities, and there is only a partially met need for the control of cervical cancer. There is no nationally organised cervical cancer screening programme in India as in West.
Indian public specially women needs to be made aware and conscious about annual gynaecological check-up as most Indian women and girl students are unaware of cervical cancer risk and know nothing about it. A study of more than 3,000 female students shows that they were no better informed about the disease than their male counterparts. Less than one per cent could relate this cancer to be sexually transmitted.
Vaccination can also protect against HPV infection, which is the proven necessary cause of cervical cancer. Vaccination is a primary prevention tool that can be used among young girls and women with no clinical evidence of disease and should be integrated in existing health services, once it is available in world market i.e late 2006-2007.
(The writer is Chairperson of Women Wing of IMA.)