Most cases of colon cancer begin as small noncancerous polyps. Over time these polyps may become colon cancers. Regular screening helps identify polyps before they become cancerous, allowing for prophylactic treatment.
According to the American Cancer Society, 112,000 people are diagnosed with colon cancer annually.
The most common and effective diagnostic procedures is the oft-dreaded colonoscopy. It is recommended that individuals 50 and up get one – some 90% of colon cancers occur in this age group.
During the exam, a colonoscope, a long, slender, flexible tube attached to a video camera is used to view the colon and rectum. Polyps found during the procedure are typically biospied and analyzed.
A new technique being developed at the Stanford University School of Medicine may one day detect colon cancer without a biopsy – including early stage cancers that have not yet become polyps.
The study, led by Dr. Christopher Contag, used a unique protein that sticks to colon cells in the early stages of cancer. The protein was attached to a “fluorescent beacon”.
When sprayed into the colon, and viewed with a Mauna Kea Technologies’ miniaturized microscope, CellVizio, researchers were able to see fluorescent patches where the protein had attached to cancerous cells.
The fine resolution afforded by the technique (researchers could spot individual cancer cells) will allow for the detection of even early stage cancers.
In the initial trial with 15 patients, the Contag detected 82% of cancerous polyps. Contag believes that by working with additional proteins, the technique will become even more accurate.