Colon and rectum are parts of your large intestine. A cancerous lesion within that area is referred to as colorectal cancer. This type of cancer usually arises by the formation of a clump of cells, called a polyp. These polyps can then progress into cancerous tumors. It is thus quite important to get screened for these, so they can be treated before their development into tumors.
A tumor develops when the DNA within cells undergo mutation and start replicating abnormally. The exact cause behind colorectal cancer is not known, but following are some risk factors:
- Old age
- High fat, low fiber diet
- Sedentary lifestyle
- Positive family history
- Past history of colonic polyps or colorectal cancer
- Inflammatory conditions of bowel
- Inherited syndromes that increase risk
- Diabetes or obesity
- Radiation therapy
Most cases begin as asymptomatic and each case may vary in its presentation depending on the size and precise location of the tumor. Some common symptoms include:
- Abdominal discomfort or pain
- Bloody stool
- Change in bowel habits or consistency of the stool
- Diarrhea or constipation
- Unexplained weight loss
- Weakness or fatigue
Screening is highly recommended for individuals to avoid the morbidity associated with colorectal cancer. Stool analysis and Colonoscopies are two screening methods most widely used. For diagnosis, endoscopic examination of the intestine, as well as blood tests and CEA (Carcinoembryonic antigen) a chemical produced by the colon, may be used.
Treatment is mainly based on three options: surgery, chemotherapy, and radiotherapy. The choice of treatment varies on the basis of specification of the tumor.