Colorectal cancer is a cancer that starts in the colon or the rectum, and may be called colon cancer or rectal cancer or colorectal cancer. Most colorectal cancers begin as a growth called a polyp on the inner lining of the colon or rectum. Polyps are benign growths that can vary in size from less than a quarter of an inch to several inches. Some types of polyps can change into cancer over the course of several years, but not all polyps become cancer

Colorectal Cancer Symptoms and Diagnosis

Colorectal cancer symptoms may not appear in the early stages of cancer. However, they may include:

  • A change in bowel movements
  • Rectal bleeding
  • Blood in the stool, which can make the stool darker than normal
  • Cramping or abdominal pain
  • Weakness or fatigue
  • Unexpected weight loss
Colorectal cancer diagnostic tests may include:
  • Colonoscopy: Because colonoscopy is the most accurate way to detect polyps, experts recommend colonoscopy as a screening method so that any polyps found can be removed immediately – removing the possibility that they may become colorectal cancer.
  • Biopsy. If abnormal polyps are discovered during colonoscopy, tissue sample from the polyp will be reviewed by a pathologist. Only a biopsy can make a definite diagnosis of colorectal cancer.
  • Molecular testing of the tumor: Your doctor may recommend running genomic tests on a tumor sample to identify specific genes or other factors unique to your tumor.

Colorectal Cancer Treatment

Colorectal cancer treatment will include:

  • Surgery – can either be an open (extended) procedure, or laparoscopic, which uses small keyhole incisions. BIDMC surgeons are acclaimed for their technical proficiency and experience in laparoscopic colectomy, a minimally invasive operation to remove part of the large intestine to treat cancer. Laparoscopic colectomy is one of the more technically challenging procedures in the field of surgery because the colon is not a fixed target, and so the operation is rather like picking up spaghetti with chopsticks. Still, most people are candidates for laparoscopic colectomy — with excellent outcomes at BIDMC — due to our surgical expertise and the volume of procedures we perform. Studies show that laparoscopic colectomy, because it uses smaller incisions compared to an open procedure, may decrease your risk in developing a hernia or bowel obstruction following surgery. Smaller incisions also mean better pain control and faster recovery.
  • Chemotherapy: If the colon cancer has spread to your lymph nodes, then you will most likely need chemotherapy following surgery. You will see a medical oncologist — a doctor who treats cancer with chemotherapy and other systemic medicines, such as biological therapy. Chemotherapy travels through the bloodstream to kill cancer cells. BIDMC has a specialized outpatient medical oncology unit for outpatient oncology evaluation and treatment, and a specialized inpatient medical oncology floor for inpatient oncology care.

Learn More

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