SCRT in TNT With or Without Chlorophyllin

The current standard treatment for locally advanced rectal cancer includes neoadjuvant (treatment given before Surgery) radiotherapy \& chemotherapy followed by surgery if needed or wait and watch in patients whom tumour has completely regressed. It has been observed that even after receiving this intensive treatment patients, almost 70% of patients develop acute toxicity (during or within 3 months) of grade 2 or higher (needing medication for toxicity). This affects their treatment tolerance, completion and quality of life. In this study Researchers are going to see if addition of drug Chlorophyllin (derived from green plant leaves) along with standard treatment would help in reducing the acute toxicity. Chlorophyllin is present in all green leaves of plants giving them green color. The drug is derived from green plant leaves. As it is a plant-based product it is safe for humans and has no known side effects of its own. This is a randomized study which has two arms; Arm 1 is test arm where participants will receive drug of interest (Chlorophyllin) and in other arm participants will receive Placebo. Upon successful completion of study, outcomes from both the study arm will be compared and participants will be followed by standard protocol for 3 years.