“Vaccination is the solution for India to contain cervical cancer”January 6, 2020
It is high time for India, home to the second largest population with cervical cancer, to get its act together. The country that contributes about 20% of the world’s estimated 3.6 lakh cervical cancer deaths every year also has the dubious distinction of having the highest death-to-incidence ratio. This is largely due to late-stage reporting. We need to move quickly to increase awareness about the disease. If the country wants to hit its target of eliminating the disease, extensive screening and vaccination are the only way forward, says Dr Rengaswamy Sankaranarayanan, Chief of the Cancer Screening Group at the International Agency for Research on Cancer in Lyon, France
How alarming is the incidence of cervical cancer in India?
Globally, we estimate that in 2018, around 530,000 new cases of cervical cancer have been recorded, out of which 96,000 are contributed by India and about 110,000 are contributed by China. We also estimate that about 360,000 cervical cancer deaths happen around the world, out of which about 70,000 are contributed by India, forming a major proportion. The number of people dying from cervical cancer, or the death-to-incidence ratio, is high in India because most of our women present it at the late stage of 3 and 4. With most detected cases being stage 3 and stage 2, cure rates are very low and the disease ultimately kills them. But if you can detect these cancers early, like at stage 1, cure rates can exceed 90-95%. More than that, we can even detect them in what we call stage zero — before we call it carcinoma in situ or severe dysplasia or high grade squamous epithelial lesion. These are called stage zero cancers. If you detect them at that stage, which is possible only by screening, you can treat them with very simple forms of outpatient treatment — by excising it, or by applying a probe which is made to cool to -60oC or by applying a probe which is heated to 100oC, also known as thermocoagulation. This way, you can achieve a 100% cure rate and prevent cancer.
How can awareness and screening programmes be made available to everyone in the country?
It is true that we need to give proper awareness and screening opportunities for every eligible woman in India. But for that, we need to have trained healthcare providers and good treatment facilities, and that is something which can only be done by the government.
What are the challenges of treatment in India and what are the solutions?
Women have to come forward, and this will depend upon awareness and the proximity of available services. Suppose somebody has to travel 100 kms to get a screening? People will not go. So, these are all very important. [Right now] it is only available in very few places. Tamil Nadu is the only state which has developed a screening programme. They have screening outlets. In all the 1,652 primary health centres in the state, screening for oral cancer, breast cancer, cervical cancer, and high blood pressure and diabetes are available. They have appointed nurses specifically to do this. We have to train nurses and appoint them specifically for detecting non-communicable diseases.
For developing proper screening, we will need to invest a lot, and even if mass screening is done, it may create problems since there won’t be enough centers to treat the patients immediately.
If you do a screening programme without adequate facilities for diagnosis and treatment, it will lead to overcrowding, and result in a negative impact. Screening involves several steps. It involves diagnosis, treatment and repeated screening every 5 or 10 years. So it is a long affair. Compared to that, vaccination is a one-time affair. You give it when the girls are young, before they get sexually active. If a woman is infected with a virus, the vaccine does not work, so they have to be caught before the initial sexual activity. If you catch a girl between 9-11 year old, you can prevent 70-80% of cervical cancer cases caused by HPV type 16 and 18 even with a single vaccine. If you give two doses at 6 months apart or 12 months apart, which is what WHO currently recommends, you can prevent a lot of cancers. So, that is one-time prevention. This is a big advantage. Just like India is polio-free because of the oral polio vaccination, and we have eliminated neonatal tetanus because every newborn child and pregnant mother is vaccinated with tetanus toxoid. Similar is the case of the triple vaccine which we give in the first year of life, which prevents diphtheria, whooping cough and tetanus. It is all because of the intervention with vaccines.
How can we make it cost-effective?
At the moment, vaccines are costly because whenever you develop a new drug, the companies would like to take back a certain amount to make a profit. Then several people will start making it and, as the demand increases, competition goes up, and the drug price will fall. So now, it is possible for governments in developing countries to buy a vaccine by negotiation for each dose at around 5-10 dollars. Besides, there is a new vaccine being evaluated in India, while in China, 11 vaccines are being evaluated. They will soon come to the market. When all these vaccines come in, naturally cost will go down, and that will make accessibility to vaccines better. That is what we are waiting for.
Is prescribing HPV vaccine an answer for India to fight against cervical cancer?
India is, in fact, a conglomeration of many countries. Various states are in different stages of development. When we take the case of Kerala as an example, it is completely different from many of the other states. The unique feature about Kerala is that cervix cancer incidence is already lower in that state. For every 100,000 women in Kerala, about 9 women develop cervical cancer every year. But when you go to rest of India, for 100,000 women anywhere between 25-40 women develops cervix cancer. So, for the rest of India, what I am recommending is that in addition to vaccination, they should provide at least a single round of screening between the ages of 35 and 39, preferably with HPV testing, because HPV is the cause for cervical cancer. So, if you find a woman already infected with HPV, then you can focus on early detection and detection of stage zero in these people, so that you can prevent it. For the rest of India, I propose a combination of vaccination plus at least a once-a-lifetime screening for females between 30-49, depending upon how much money the government can contribute.
How reliable is pap smear test in cervical cancer screening?
Pap-smear is a time-tested early diagnosis test. It worked very well in the early years, but it requires considerable quality assurance. It involves staining with different chemicals, and the way you take the smear and stain it and read it, all requires a lot of quality assurance. Unless you are careful with all these, pap smear results are not that good.
Are we moving towards the elimination of cervical cancer?
With vaccination, we aim to bring about the elimination of cervical cancer. If you bring down the level of cervix cancer below 4 per 100,000, then it is elimination, but if you stop vaccination and other measures, it will come back again.