The field of cancer treatment is seeing significant advancements through immunotherapy, particularly with PD1 blockade therapy. In a recent medical trial in the USA, 12 patients were diagnosed with rectal cancer were completely cured without the need for surgery or chemotherapy using monoclonal antibody dostarlimab. This pioneering study was conducted by doctors at the Memorial Sloan Kettering Cancer Centre in New York.
Findings of the Trial: Revolutionising Rectal Cancer Treatment
This groundbreaking trial showed that immunotherapy alone could entirely cure mismatch repair deficient cancer without resorting to standard treatments like chemotherapy, radiotherapy, or surgery. Mismatch repair deficient cancer is common among colorectal, gastrointestinal, and endometrial cancers. Patients with this condition lack certain genes needed to correct naturally occurring errors in DNA as cells multiply.
Immunotherapy utilises the patient’s own immune system to combat cancer. It enhances or alters how the immune system operates, enabling it to detect and destroy cancer cells. Immunotherapy falls under a category known as PD1 blockades, now recommended for treating such cancers over traditional methods.
The Importance of PD1 Therapy
PD1, a type of protein, regulates several functions of the immune system, including suppressing T cell activity. PD1 blockade therapy aims to liberate T cells from this suppression. T cells are white blood cells vital for building immunity against common pathogens or antigens.
Previously, PD1 therapy was used post-surgery, but the study demonstrated that surgery might not be necessary. While traditionally administered for cancers that have metastasised, or spread beyond their original location, PD1 therapy is now recommended for all mismatch repair deficient cancers. This is due to its quicker improvement rates and lesser toxicity compared to conventional chemotherapy and radiotherapy. Avoidance of these conventional treatments can enhance a patient’s quality of life by preserving fertility, sexual health, and bladder and bowel functions.
Immunotherapy’s Accessibility in India
Despite its clear advantages, the challenge with immunotherapies is their high cost, making them unaffordable for the majority in India. An immunotherapy treatment can cost around Rs 4 lakh per month, with patients needing the treatment for six months to a year.
The field of precision medicine, employing specific immunotherapy drugs for distinct types of cancers, is still in its infancy in India. This approach, which takes into account individual variability in genes, environment, and lifestyle, would allow medical professionals and researchers to more accurately predict which treatments and prevention strategies will work for different patient groups.
Relevance to UPSC Civil Services Examination
The recent advancements in cancer treatments and their potential implication for public health often form part of the civil services examination. For instance, the term ‘ACE2’, involved in the spread of viral diseases such as COVID-19, appeared in the examination in 2021. ACE2 is an enzyme that generates smaller proteins by breaking down larger ones, regulating cell functions. The SARS-CoV-2 virus uses its spike-like protein to bind to ACE2 – similar to a key fitting into a lock – before entering and infecting cells. Understanding such medical terminologies and their implications are crucial for aspirants preparing for examinations.