Here is a scenario that explains clearly what genomic medicine can do for us specifically when it comes to cancer treatment. Two people of the same age go to an oncologist with the same type of cancer at the same stage. Taking all the clinical evidence available into account the doctor chooses the same treatment approach for both these patients. Four months later, the doctor finds that while one patient has responded well to the treatment, the other patient has not been so fortunate and now the doctor must look for a second line of treatment. Meanwhile, the problem has already become more complex because the tumour has progressed to a more advanced stage. Now, the patient is faced with longer treatment and at a higher cost. This is a common scenario for many oncologists and I am sure you are tempted to ask the same questions that oncologists ask: why did one patient respond to treatment while the other did not? My answer would be that right now we have no way of predicting a sure positive treatment outcome for our cancer patients. All we know is that we need to treat cancer the right way, the first time. This is where genomic medicine comes in. The word “genome” refers to all the DNA present in a person’s body. Our DNA is the “instruction manual” present in most of the body’s cells and contains intricate details, in the form of a DNA sequence, that instruct the cells how to behave. Changes in the sequence of this DNA can cause several diseases, including many of the cancers. Analysis of the genome can give much insight on how cancers develop, progress and how they can be controlled and treated. “Genomic medicine”, derived from these insights uses a patient’s genomic information to arrive at a diagnosis or decide on the most suitable treatment.
I firmly believe that more and more cancer treatment centres and hospitals across the country must incorporate genomic medicine in their regular clinical practice because it can revolutionise cancer screening, diagnosis and treatment. Genetic testing also gives us the option of screening those with a hereditary risk of cancer to identify high-risk patients who would benefit from regular monitoring. Earlier, doctors asked for multiple tests, each of which looked for a single mutation in a single gene leading to a “one size fits all” view of possible therapies. Today, we can carry out “massively parallel deep sequencing” of genes to reveal the multigene mutation profile of a tumor at “one go”, giving us a comprehensive understanding of the processes that drive an individual’s cancer.
Whenever we speak of any new way to diagnose or treat a condition in the Indian context, accessibility is an important consideration. Advanced technologies are usually made available in larger hospitals and centres in metro and Tier-1 cities because of the higher number of patients and skilled healthcare professionals in these areas. In my opinion, we must also establish cancer care centres in Tier 2 and Tier 3 cities, which can offer genomic medicine, help to raise awareness about cancer, treat patients the right way the first time and bring down the overall cost of cancer treatment.
Affordability is a very important consideration in the Indian context since most patients do not have an adequate insurance cover and must bear heavy out-of-pocket expenditure when it comes to health. Over the years, the cost of sequencing a person’s genome has reduced rapidly, thanks to new technologies such as next-generation sequencing. For example, genome sequencing that would cost just above $4,000 (over Rs 2.5 lakh) in mid-2015 fell to less than $1,500 (less than Rs 1 lakh) by the end of the year. I predict that in a few years from now, we will be able to sequence a patient’s genome for as little as Rs 10,000-Rs15,000, which will put genomic medicine in the reach of a much larger proportion of the Indian population.
As of now, most research studies that have identified genomic variations and their implications for cancer care have largely been conducted amongst Caucasian populations. We need to carry out India-specific research to look for variations that are specific to our people. This is why we must set up an Indian cancer genome bank, along the lines of the Indian Genome Variation Consortium which was established a few years ago.
Ultimately, genomic medicine can only become a part of a countrywide oncology practice when it is accessible and affordable for all Indians.
-BS Ajaikumar, Chairman and CEO, HealthCare Global Enterprises Ltd.