Overview

Colorectal cancer (CRC) is a type of cancer that begins in the colon or rectum, parts of the large intestine. It often starts as small, noncancerous polyps that can develop into cancer over time. Colorectal cancer is one of the most common cancers worldwide, particularly in developed countries. The risk of developing CRC increases with age, and it is often diagnosed in individuals over the age of 50. Early detection through screening is crucial, as it significantly improves the chances of successful treatment.

Causes

The exact causes of colorectal cancer are not fully understood, but several risk factors have been identified. These include genetic predisposition, with certain inherited syndromes like Lynch syndrome and familial adenomatous polyposis (FAP) increasing the risk. Lifestyle factors such as a diet high in red and processed meats, low physical activity, obesity, smoking, and heavy alcohol consumption are also linked to higher CRC risk. Additionally, chronic inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis, can increase the likelihood of developing colorectal cancer.

Treatments

The treatment of colorectal cancer depends on the stage of the disease. Early-stage CRC is typically treated with surgery to remove the cancerous polyps or sections of the colon or rectum. If the cancer has spread to nearby lymph nodes, chemotherapy may be recommended to kill any remaining cancer cells. Radiation therapy is also used, particularly for rectal cancer, to shrink tumors before surgery or to kill cancer cells that may remain post-surgery. In advanced stages, targeted therapies and immunotherapies may be employed, focusing on specific genetic mutations or enhancing the body's immune response to fight the cancer.