Colorectal cancer is a term used to describe malignant tumors that form in the colon (large intestine) and rectum, both vital parts of the digestive system. While colon cancer and rectal cancer are often grouped together, each has distinct anatomical locations and some clinical characteristics that may vary. Fortunately, both types are highly treatable when detected early. In this article, we’ll explore the causes of colorectal cancer, common symptoms of colon and rectal cancer, risk factors, and the latest treatment options available.
What is Colon Cancer?
Colon cancer develops when small cell growths called polyps, which form on the inner lining of the large intestine, gradually turn into cancer over time. Approximately 90% of all colorectal cancer cases originate from these polyps. The likelihood of developing such polyps increases significantly after the age of 50, which also raises the overall risk of colon cancer.
What Are the Causes of Colon Cancer?
Although the exact cause is unknown, certain lifestyle and genetic factors play a role in the development of colon cancer. The most common risk factors include:
- A diet high in fat and low in fiber
- A family history of colon cancer, especially in first-degree relatives
- Inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease
- A sedentary lifestyle and obesity
- Smoking and alcohol consumption
What Are the Symptoms of Colon Cancer?
Colon cancer often shows no symptoms in its early stages. However, as the disease progresses, it may present with the following signs:
- Blood in the stool (bright red or dark-colored)
- Changes in bowel habits, such as constipation or diarrhea
- Narrowing of stool (thin or ribbon-like stools)
- Tenesmus (a feeling of incomplete bowel evacuation)
- Fatigue, Weakness, and Anemia Due to Iron Deficiency
What Is Rectal Cancer?
Rectal cancer refers to malignant tumors that develop in the last 12–15 cm of the large intestine, known as the rectum. Because of its anatomical proximity to pelvic structures, rectal cancer may differ from colon cancer in terms of surgical approach and treatment planning.
Risk Factors for Rectal Cancer
Rectal cancer typically occurs in individuals over the age of 40. While its risk factors are similar to those of colon cancer, certain conditions may specifically increase the risk of developing rectal cancer:
- Hereditary cancer syndromes (e.g., FAP, Lynch syndrome)
- Family history of colorectal cancer or polyps
- A personal history of breast, ovarian, or endometrial cancer
- Previous exposure to radiation
Symptoms of Rectal Cancer
- Changes in bowel habits
- Rectal bleeding, including bright red or dark-colored blood in stool
- Abdominal discomfort such as gas, cramping, or bloating
- Unexplained weight loss
- Persistent Fatigue
Early Detection Saves Lives: Colonoscopy as the Gold Standard
Most colorectal cancers begin as non-cancerous polyps and can be detected before becoming malignant. For early diagnosis, colonoscopy remains the gold standard. Screening should begin at age 50, or earlier (e.g., at 40 or 10 years before the age at which the disease was diagnosed) if there is a family history of colon cancer.
Other Diagnostic Methods
- Fecal occult blood test (FOBT)
- Digital rectal examination (DRE)
- Proctoscopy
- Biopsy
- CEA test (carcinoembryonic antigen)
Treatment Options for Colorectal Cancer
Surgical Intervention:
Surgery is the primary treatment for both colon and rectal cancers. The affected section, along with surrounding tissues and lymph nodes, is removed. In rectal cancer, surgical planning is more complex due to the need to preserve muscles that control bowel movements near the rectum.
Laparoscopic (Minimally Invasive) Surgery
Today, laparoscopic techniques are commonly preferred. These approaches result in faster recovery, less pain, and minimal scarring compared to traditional open surgery.
Chemotherapy and Radiotherapy
In many rectal cancer cases, preoperative radiation and chemotherapy are used to shrink the tumor and increase the chances of preserving the anal sphincter. This approach can reduce the need for a permanent colostomy.
Watch: What Is Colon Cancer?
Conclusion: Early Detection Saves Lives
Colon and rectal cancers are highly treatable when detected early. People over the age of 50 and those in high-risk groups should undergo regular screenings. Paying attention to changes in bowel habits can lead to earlier diagnosis and better treatment outcomes.
