Colon cancer is the growth of malignant cells in the colon.
Cancer of the colon is a highly treatable and often curable disease when localized to the bowel. Surgery is the primary form of treatment and results in cure in approximately 50% of the patients. Recurrence following surgery is a major problem and is often the ultimate cause of death.
Because of the frequency of the disease, ability to identify high-risk groups, slow growth of primary lesions, better survival of patients with early-stage lesions, and relative simplicity and accuracy of screening tests, screening for colon cancer should be a part of routine care for all adults aged 50 years and older, especially for those with first-degree relatives with colorectal cancer.
Increasing age is the most important risk factor for most cancers. Other risk factors for colorectal cancer include the following:
- Family history of colorectal cancer in a first-degree relative
- Personal history of colorectal adenomas, colorectal cancer, or ovarian cancer
- Hereditary conditions, including familial adenomatous polyposis (FAP) and Lynch syndrome (hereditary nonpolyposis colorectal cancer [HNPCC])
- Personal history of long-standing chronic ulcerative colitis or Crohn colitis
- Excessive alcohol use
- Cigarette smoking
- Race/ethnicity: African American
Treatment decisions depend on factors such as physician and patient preferences and the stage of the disease, rather than the age of the patient. Treatment options include surgery, chemotherapy, and radiation.
The prognosis of patients with colon cancer is clearly related to the following:
- The degree of penetration of the tumor through the bowel wall.
- The presence or absence of nodal involvement.
- The presence or absence of distant metastases.
These three characteristics form the basis for all staging systems developed for this disease.
Other prognostic factors include the following:
- Bowel obstruction and bowel perforation are indicators of poor prognosis
- Elevated pretreatment serum levels of carcinoembryonic antigen (CEA) have a negative prognostic significance