Colorectal Cancer

Colorectal cancer is cancer that begins in the colon (the area of the intestine responsible for absorbing water and salt from solid waste) or the rectum (the part of the intestine responsible for storing and getting rid of solid waste). More than 95 percent of colorectal cancers are adenocarcinoma, a cancer type that starts in cells that line the colon and rectum.

Regular colorectal screening beginning at age 50 is recommended for individuals with normal risk. For younger individuals with higher risk, screening should be done earlier and more frequently.

Staff at NewYork-Presbyterian's Cancer Prevention Program provides guidance to patients about genetic testing and screening methods to detect cancers, including colorectal cancer. Should cancer be present, the Hospital has several centers dedicated to treatment. These include the Jay Monahan Center for Gastrointestinal Health, the Center for Advanced Digestive Care, and the Herbert Irving Comprehensive Cancer Center.


Symptoms of colorectal cancer vary considerably, with some people having no symptoms. Symptoms of colorectal cancer may resemble other conditions, so always consult a physician if you experience any of the following symptoms:

  • A change in bowel habits, such as constipation, diarrhea, frequency of bowel movements, or narrowing of the stool that continues for more than a few days
  • Rectal bleeding or traces of blood in the stool
  • Stomach pain, cramping, or stomach discomfort
  • Fatigue and weakness
  • Decreased appetite and weight loss
  • Jaundice (yellow-colored skin or eyes)
  • Enlarged abdomen
  • Feeling of discomfort in the pelvic area

Risk Factors

A sedentary lifestyle; a diet low in fresh fruit, vegetables, whole grains, calcium, and vitamin D; high red meat consumption; excess body fat; tobacco use; heavy alcohol use; and diabetes may increase the risk of colorectal cancer.

While older age is a risk factor, people with certain genetic syndromes may develop the disease at a younger age. In addition, people with other types of cancer or digestive diseases may be at greater risk for developing colorectal cancer.

Individuals of Ashkenazi Jewish background may have a higher than normal risk of colorectal cancer. In addition, African Americans who are diagnosed with this disease are more likely than other groups to die of it.


Tumors may bleed causing patients to have blood in their stool and/or low red blood cell counts (anemia). Therefore, doctors may initially perform blood tests to determine if colorectal cancer is present.

If these tests reveal an abnormal condition, doctors may next perform a colonoscopy or sigmoidoscopy to examine the colon and determine the cause of bleeding. Both procedures use an endoscope (a flexible tube equipped with a light and camera) that is inserted into the rectum and guided into the colon. A colonoscopy examines the rectum and entire colon. It is more comprehensive, but requires greater preparation on the part of the patient and the use of sedation. A sigmoidoscopy requires less preparation but is less comprehensive since it only examines the rectum and bottom of the colon.


Surgery, chemotherapy and targeted therapy (a new class of agents that destroy only cancer cells and leave healthy cells unharmed), and radiation therapy are used (sometimes in combination) to treat colorectal cancer. Which treatments are chosen depends on the stage of the cancer -- how advanced it is.

For colon cancer, the most commonly performed surgery is a segmental resection, in which the tumor is removed along with a section of normal colon on either side of the cancer and nearby lymph nodes. The sections of the remaining colon are then reattached. This procedure is often performed laparoscopically.

For rectal cancer, surgery involves removal of the cancerous tumor and repair of the rectum.

Prior to colorectal cancer surgery, chemotherapy and radiation may be used to shrink the size of a tumor. This is especially important if the tumor is near a critical area such as an artery or is near an internal organ.

Following surgery, chemotherapy, radiation, or targeted therapy may be used to destroy any remaining cancer cells. These agents also may be used instead of surgery for patients with advanced cancer or for whom surgery is not possible, to minimize the effects of the cancer and the symptoms the patients may experience.


Digestive and Liver Diseases


Center for Advanced Digestive Care
NewYork-Presbyterian/Weill Cornell