Colorectal cancer, also known as bowel cancer, colon cancer, or rectal cancer, is one of the most common types of cancer worldwide. It’s a malignancy that begins in the colon or rectum, parts of the large intestine in the digestive system. This disease can affect men and women of all ethnic backgrounds. However, it’s more common in individuals over 50, and its incidence increases with age.
The Biology of Colorectal Cancer
Colorectal cancer starts with the growth of precancerous polyps on the inner lining of the colon or rectum. These growths can evolve over time into malignant tumors. The two most common types of polyps are adenomas and hyperplastic polyps, with the former having a greater risk of developing into cancer.
Like all forms of cancer, colorectal cancer begins when the body’s cells divide and grow uncontrollably. Changes or mutations in the DNA within cells can disrupt the normal cell life cycle, leading to this unregulated growth. If these abnormal cells accumulate, they can form a tumor and, in some cases, spread to other parts of the body (metastasis).
Several factors may increase your risk of colorectal cancer, including age, personal and family history of colorectal polyps or colorectal cancer, certain genetic syndromes (such as Lynch syndrome or familial adenomatous polyposis), long-standing inflammatory diseases of the colon (like ulcerative colitis and Crohn’s disease), diet (especially a diet low in fiber and high in fat), physical inactivity, obesity, smoking, and heavy alcohol use.
Colorectal cancer symptoms can be quite varied and depend on the location of the tumor in the bowel, and whether it has spread elsewhere in the body. Symptoms may include changes in bowel habits, persistent abdominal discomfort, rectal bleeding or blood in the stool, weakness and fatigue, or unexplained weight loss. However, it’s essential to remember that these symptoms can also be due to conditions other than colorectal cancer, such as infection, hemorrhoids, or inflammatory bowel disease.
Screening and Diagnosis
Screening for colorectal cancer is crucial because it can help detect the disease at an early stage, even before symptoms develop. The most common screening tests are the fecal occult blood test (FOBT), fecal immunochemical test (FIT), stool DNA test, sigmoidoscopy, and colonoscopy. These tests seek to identify abnormal changes or detect hidden blood in the stool, which could be an indication of cancer.
Colorectal cancer treatment depends on the stage of the cancer, the location of the tumor, and the patient’s overall health. The main treatment modalities include surgery, chemotherapy, and radiation therapy.
Surgery is often the first-line treatment for early-stage colorectal cancer. The surgeon may remove the tumor along with a small amount of surrounding healthy tissue. For later-stage cancers, more extensive surgery may be required.
Chemotherapy uses drugs to kill cancer cells, typically after surgery (adjuvant therapy) to kill any remaining cancer cells, or before surgery (neoadjuvant therapy) to shrink large tumors.
Radiation therapy uses high-energy rays to kill cancer cells and may be used in combination with chemotherapy as neoadjuvant therapy or to alleviate symptoms in advanced colorectal cancer.
Advances in medicine have also led to the development of targeted therapies and immunotherapies, which aim to more specifically target cancer cells, minimizing harm to healthy cells.
Despite its prevalence, colorectal cancer is one of the most preventable forms of cancer. Regular screening, a balanced diet rich in fruits, vegetables, and whole grains, regular physical activity, and avoiding tobacco and excessive alcohol, can significantly reduce the risk of developing this disease.
Moreover, colorectal cancer is also highly treatable if detected early. This is why it’s crucial to participate in regular screenings and promptly address any symptoms with your healthcare provider.
In recent years, advancements in technology and medical research have led to improved diagnostic tools and treatments for colorectal cancer. Personalized treatments, based on the genetics of each patient’s tumor, have shown significant promise in improving survival rates and minimizing side effects.
Lastly, surviving colorectal cancer doesn’t end with the completion of treatment. Survivors often need ongoing care, monitoring, and support to manage potential side effects of the disease and its treatment, adjust to life after cancer, and maintain good health.
With increased awareness, early detection, and advancements in treatment, we can make significant strides in reducing the impact of colorectal cancer. It’s a battle worth fighting, and together, we can make a difference.