Colorectal or colon cancer is cancer that affects a person’s rectum, colon, or both, better relatable as the large intestine. The incidences of colon cancer are on the rise among young adults with poor dietary habits being one of the contributors. According to the Indian Council of Medical Research (ICMR), colon cancer is the third-most common cancer among men, worldwide. In India, the annual incidence rates for colon cancer and rectal cancer in men are 4.4 and 4.1 per 1,00,000, respectively. The annual incidence rates for colon cancer in women are 3.9 per 1,00,000.

People with ulcerative colitis & Crohn's disease are at a higher risk. The factors that can increase the chance of being affected by colorectal cancer are smoking, obesity, alcohol consumption, sedentary lifestyle, older age, and a diet high in fat, red meat, processed meat, and low in fibre apart from genetic reasons. A diet too rich in red meat is related to a higher risk of colon cancer. Also, it’s highly suggested to avoid processed non-vegetarian food products to lower the risk. 

With screening and early detection, these patients can be cured in the majority of the cases. Methods to screen colorectal cancer are digital rectal examination, stool test to detect blood & colonoscopy in high-risk individuals. Colonoscopy is a test that is used to look inside the rectum and full length of the colon. The screening can start after 50 years of age but can be early in people having a strong family history of colorectal cancer. About 5 per cent of people who develop colorectal cancer have inherited gene changes (mutations) that cause family cancer syndromes and can lead to them getting the disease. The most common inherited syndromes linked with colorectal cancers are Lynch syndrome (hereditary non-polyposis colorectal cancer, or HNPCC) and familial adenomatous polyposis (FAP), but other rarer syndromes can also increase the risk of colorectal cancer. 

Once the diagnosis of cancer is confirmed, then a CT scan or a PET scan is done to evaluate the extent of the spread of cancer and based on the report, the oncologist will suggest the future course of treatment. Colorectal cancer can be treated by surgery, chemotherapy & radiotherapy in various combinations depending on the stage of cancer. When detected early & on timely treatment, most of the rectal cancers can be operated in a way where natural anal orifice can be maintained allowing normal passage of stools. With the improvement in radiation & surgical techniques, the treatment is now much safer, tolerable, and effective. In localised & early-stage cancer the survival rates are around 90 per cent. For stage IV cancer where the disease is spread to other parts of the body, chemotherapy becomes the main treatment modality. Post- treatment periodic follow up is advised & is very important to assess the recovery rate & timely interventions if ever required. 

Prevention is always better than cure and one can reduce the risks of developing colorectal cancer by leading an active lifestyle comprising of regular exercises, consuming a rich plant based diet comprising of fruits, vegetables, nuts, and whole grains, as well as fish, and avoid processed meat and red meat as much as possible. A periodic screening for colorectal cancer is very important along with the above mentioned precautions. One should be equally aware regarding the disease, share with closed ones, and thus reduce the incidences of colon cancer by being alert. 

Dr Manish Chomal, Medical Director, Senior Consultant & Head - Radiation Oncology Services, HCG Hospital, Jaipur