MedifocusHealth

History and Physical Examination

Evaluation of patients with suspected colorectal cancer begins with a thorough patient history followed by a physical examination. In taking the patient's history, the doctor will focus particularly on symptoms (e.g., bloody stools; black/tarry stools; changes in bowel habits; abdominal/rectal discomfort) that may be associated with colorectal cancer.

Following the patient history, the doctor will perform a physical exam that focuses on the following:

• Abdominal Exam - this is a simple non-invasive examination of the abdomen consisting of visualization, auscultation (listening) with a stethoscope for bowel sounds, and palpation by hand to assess for tenderness, distention, enlargement of the liver or spleen, or the presence of obvious masses.

• Digital Rectal Exam (DRE) - DRE is the common examination practice of inserting one gloved and lubricated finger into the rectum allowing palpation of the anus, the lower part of the rectum, and the prostate gland. Despite its widespread use, fewer than 10% of colorectal cancers are located within the 7-8cm reach of an examining finger. Stool obtained during a DRE is not thought to be adequate to screen for the presence of blood.

Laboratory Evaluation

If your doctor suspects that you may have colorectal cancer, a sample of your blood will be sent to a laboratory where the following tests will be performed:

• Complete blood count (CBC) - helps to determine the presence of infection (usually reflected in an elevated white blood cell count) or anemia (low red blood cell count).
• Blood chemistries - to evaluate kidney function and electrolyte balance (potassium, sodium, chloride).
• Urinalysis and Urine culture - to evaluate for the presence of infection as well as to measure kidney function.
• Carcinoembryonic antigen (CEA) - CEA is a blood test that measures the amount of a protein that may appear in the blood of persons with colorectal cancer (but may also be present in persons with cancer of the pancreas, breast, ovary, or lung). The CEA test is used to determine how active the cancer is and to monitor the success of treatment for colon cancer. CEA levels may be measured both before and after surgery to evaluate both the success of the surgery or to determine whether cancer has returned after treatment. The CEA level is not a valuable screening test for colorectal cancer because of the large numbers of false-positive and false-negative reports. Postoperative CEA testing should be restricted to patients who would be candidates for resection of liver or lung metastases. Two other cancer markers, CA 19-9 and CA 125, are similar to CEA and are sometimes elevated in colorectal cancer.
• Liver function tests - simple blood tests may be used to detect abnormalities in the liver that may detect metastatic disease.

Radiological Evaluation

A variety of imaging techniques are available to help doctors determine the presence of colorectal cancer as well as to help them determine if the cancer is localized to the colon/rectum or has spread to other organs of the body such as the liver, lungs, or ovaries.