What is Rectal cancer? Facts about the recent research study on rectal cancer

We spoke to Dr. Amit Rauthan, HOD and Consultant - Medical Oncology, Manipal Hospital, who talks about Immunotherapy, which has become an important treatment modality in cancer management.

The management of carcinoma rectum requires a multi-disciplinary team approach. Surgery, chemotherapy and radiotherapy are all essential modalities in treating rectal cancers. 

There is a small subgroup of rectal cancers, which is called MMR deficient or MSI high rectal cancer, which is seen in less than 3-4 % of rectal cancers. This is a unique subgroup as immunotherapy shows very good response to treatment here. 

Various immunotherapy medicines are available in India and are being used in patients with stage IV MMR deficient cancers. At our centre, we have treated patients with stage IV MMR deficient colon, stomach and uterus cancers with immunotherapy medicines and have seen good responses in many patients. Till now, immunotherapy is approved for advanced-stage diseases only.

The recent much-talked-about study presented in the ASCO 2022 meeting in the USA was a novel approach as this was done as initial treatment in early-stage rectal cancers with MMR deficiency. 

Though the study had only 14 patients, it showed that all patients had a complete response. None of these patients received surgery, chemotherapy or radiotherapy till date. This approach will need longer follow-ups and studies will need to be done on a larger number of patients to enable this approach to become first-line therapy.  

Immunotherapy has become an important treatment modality in cancer management as it does not have the side effects of chemotherapy, and also, responding patients can show very durable responses.