Medical consultation on colon cancer includes gathering of information such as symptoms, a physical examination, review of medical and family history and a series of diagnostic tests. A certain diagnosis of colon cancer requires a biopsy.
The symptoms of colon cancer include signs such as:
Blood in the stool
Increased gastric discomfort
Changes in bowel movements
Unexplained weight loss
Exhaustion or constant or unexplained weakness
There are a number of diagnostic tests that physicians use for detecting colon cancer in the subject:
- Colonoscopy – a method that allows the physician to inspect the entire colon for the presence of polyps or suspicious tumors.
- Sigmoidoscopy – a method that allows the physician to inspect the sigmoid colon for the presence of polyps or suspicious tumors.
- Imaging studies – such as CT (computerized tomography), chest x-ray, MRI (magnetic resonance imaging) and PET scan (positron emission tomography) provide detailed, precise data on the colon and other organs.
- Blood tests – tests for certain markers that are in the blood, for example:
- CEA (carcinoembryonic antigen) indicates the presence of colon cancer
- A general blood count may rule out anemia due to blood loss from a bleeding tumor
- A metabolic test panel – helps evaluate the functioning of a certain organ (such as the liver or kidneys)
During a colonoscopy or surgical procedure, tissue samples are collected and sent to a pathologist for a study. The pathologist examines the biopsy samples under the microscope and may perform genetic tests on them.
A biopsy is performed on all of the polyps that are removed during colonoscopy and in tissue that is excised during a surgical procedure. A biopsy is required for diagnosing cancer and is essential for staging colon cancer.