BENGALURU: The ‘miracle cure’ of 12 rectal cancer patients during clinical trials conducted at Memorial Sloan Kettering Cancer Center (MSK), with the Dostarlimab drug, has been appreciated by oncologists in India. They claim this trial has reiterated the importance of focusing on immunology in cancer, while so far, our focus has been on killing cancer cells.
Dr U S Vishal Rao, Head and Neck Oncologist, and Editor, Precision Cancer says, “It is definitely a big step towards efficient cancer care. Preliminary data on Dostarlimab PD1 monotherapy has been very encouraging, and this reiterates that we are moving towards a shift in thinking and activating the immune system that takes care of cancer cells on its own.”
Rectal cancer is a tumour that arises from the lowermost part of the digestive tract, just proximal to the anal canal. It usually spreads to lymph nodes which then spreads to other distant organs as the disease advances. It is usually ignored, presuming it to be piles, and detected only during the advanced stage.
The standard mode of treatment has been chemotherapy and radiation, followed by surgery and sequential chemotherapy. However, during this trial, after immunotherapy, all patients were cancer-free for up to two years.
Explaining the process, Dr Narayana Subramaniam, Consultant & HOD, Head & Neck Oncology, SSCHRC, says, “Immunotherapy allows more focused targeting of tumours with less collateral damage to the body’s normal tissue, resulting in higher response rate to medication and fewer side-effects. A 100 per cent response rate, even in a small sample size like 12 patients, is an excellent outcome.” He adds that in an Indian context, this trial reiterates two very important realities. First, as a country, we need to do more clinical trials to discover more effective and successful cancer treatments with as few side-effects as possible. Trials have been wrongly considered an avenue for experimental treatments, though they are highly regulated and structured.
Oncologists said the trials could pave the way for treating other forms of cancer in future, with studies going on for stomach, prostate and pancreatic cancers. Experts also said there is a need for further studies on larger groups of patients across the globe to establish it as a standard care for rectal cancer.
Dr Shekar Patil, renowned oncologist, says the future of cancer cure lies in molecular testing and targeted treatment. “About 5-10 per cent of patients with this condition have micro satellite instability (MSI) but 90 per cent of them don’t have high MSI. So immunotherapy drugs or some third-generation drugs act very well on such patients. Unless large studies are conducted by administering Dostarlimab on multiple patients, we cannot take these results as definitive. We need to do more studies,” he said.
Dr. Amit Rauthan, HOD and Consultant - Medical Oncology, Manipal Hospital Old Airport Road said, “This is an interesting study for patients with rectal cancer. However, this is effective only in the small segment of rectal cancer patients who are called MMR deficient or MSI - high rectal cancer, not applicable to all. Till now the study has shown very encouraging results, however, we need to have longer follow-ups and monitor to see if the patients are cured completely.”