Diagnostic tools
Our team of colorectal cancer experts uses sophisticated diagnostic tests and tools to accurately locate and stage the disease, and plan your individualized treatment.
Throughout your colorectal cancer treatment, we use imaging and laboratory tests to track the size of the tumors, monitor your response to treatment and modify your treatment if needed.
Some diagnostic evaluations available to colorectal cancer patients at City of Hope include:
Lab tests
To diagnose colorectal cancer, your physician may recommend various lab tests. Your doctor will collect a blood sample and send it to a pathologist for additional testing.
Some lab tests used at City of Hope for diagnosing colorectal cancer include:
- Genomic tumor assessment (including tumor molecular profiling and protein expression)
- Genetic testing (to assess person and family cancer risk)
- Complete blood count (CBC) test
- Liver and kidney function tests
- Tumor marker tests
- Nutrition panel
- Stool tests
Imaging tests
Gastroenterologists use imaging tests to take pictures of the inside of your body. Imaging tests can be used for cancer, find out how far it has spread, and to help determine if cancer treatment is working. Types of imaging tests may include:
Barium enema: This test is used to take X-rays of the large intestine, which includes the colon and rectum. First, a enema containing barium is delivered through a thin tube inserted into the rectum. The solution travels through the rectum and colon. Air is released into the tube to help the colon expand, making it easier for your doctor to see abnormal growths. A series of X-rays are then taken of the colon and rectum to enable your doctor to detect polyps and other suspicious tissues. The X-rays may help determine tissues that need to be examined more closely or removed in a colonoscopy.
CT scan: Scans of the chest, abdomen and pelvis are performed to determine whether colorectal cancer has spread to other parts of your body, such as the lungs or liver. The scans may also help doctors stage the cancer. CT scans are typically performed before and a various points throughout colorectal cancer treatment to help gauge the effectiveness of treatment.
MRI: MRI technology uses strong magnetic fields, radio waves and a computer to create detailed cross-sectional pictures of the colon and rectum, and is able to distinguish between normal and diseased tissue. An MRI may be helpful in staging rectal cancer.
PET/CT: This test may be used to determine whether colorectal cancer has spread to lymph nodes or other areas of the body, such as the liver or lungs. It also aids in staging the cancer.
Endoscopic procedures
Colonoscopy: For this procedure, a gastroenterologist uses a colonoscope, which is a long, flexible, lighted tube with a tiny camera attached to the end. After inserting the colonoscope into your rectum, the gastroenterologist inspects the internal lining of your colon for polyps and other abnormalities. A biopsy may also be performed to collect samples of tissues or cells for further examination.
Polypectomy: During a colonoscopy, a doctor uses a colonoscope to remove small polyps from your colon or rectum. The polyps are then analyzed in a lab to check for cancer.
Endoscopic ultrasound (EUS): An EUS helps doctors diagnose colorectal cancer, stage the disease and determine the best treatment plan for you. The high-resolution imaging this tool offers enables the doctor to carefully examine your digestive tract and nearby organs, including the pancreas, liver, gallbladder and bile duct. This technology helps detect potential tumors and identify lymph nodes in your chest and abdomen where the cancer may have spread.
Flexible sigmoidoscopy: For this procedure, a doctor uses a lighted tube with a tiny camera attached to the end to look inside your rectum and lower part of your colon for polyps or cancer sites. The doctor may also perform a biopsy to collect samples of tissues or cells for further examination.
