Diagnosis of Colon Cancer

Investigations used to detect colon cancer of large intestine are:

1> Per Rectal Examination: The physician inserts a gloved finger moistened with lubricating jelly into the patient's anal opening and feels for any detectable abnormalities. As the finger can reach for a limited distance in the anal canal, no of growths detectable by this technique is small.

2> Occult Blood in Stool: This test also called guaiac test is used to detect minute amounts of blood in the stools not visible to human eye. It indicates that there is a breach in the inner protective serous layer of the large intestine & suggests likelihood of a developing cancer.

3> Sigmoidoscopy: A soft fiber optic tube with a optical lens attached to it, is inserted into the rectum and passed into colon. It can detect all tumors of rectum and lower part of colon till it can reach.

4> Colonoscopy: This procedure is similar to Sigmoidoscopy but can reach the entire part of colon as a longer tube is inserted into the large intestine. With the patient lying on the left side under anesthesia, the anal opening is lubricated and colonoscope is gently introduced into it. The physician injects a small of amount of air into the colon to balloon out the walls of large intestine which allows free movement of colonoscope inside the colon. The suspected areas can now be inspected for abnormal growths and a small part of growth can be biopsied and subjected to microscopic examination to confirm the diagnosis.

5> Double Contrast Barium Enema: In this procedure, a mixture of air and liquid barium enema is injected into the rectum through a small tube. Barium is a radio-opaque metal which is seen on x rays. When numerous x rays are taken of the rectum filled with contrast of air and barium salt, growths inside the rectum are seen as filling defects. This can give an indication so as to the possible place to look for the suspicious growth.

6> Rectal Ultrasonography: In ultrasonography, ultrasonic sound waves are used. These waves when encounter an organ during their path, get reflected from it depending on the density and water content of that organ. The amount of sonic waves reflected is measured electronically and an image is displayed on the monitor. In rectal ultrasonography, a probe is passed into rectum from anal opening. After studying the image produced by sonic waves on the monitor, the extent of spread of the tumor to the lymph nodes and adjacent organs is evaluated.

My next article will be on "Staging of Colon Cancer".

Disclaimer: The information contained in this article is for the general public awareness only. The patient is advised to take proper medical opinion before undergoing any treatment mentioned herein. The author and publisher are not responsible for any consequences thereof.

Published by Dr. Kiran Paranjape on May 10, 2006 01:38 PM | TrackBack