New Technologies Promise Immediate Diagnosis for GI Patients

Confocal laser endomicroscopy (CLE) effectively and immediately identifies suspicious patterns and precancerous cells and may eliminate the need in many cases for biopsy to diagnose gastrointestinal (GI) conditions. This could lead to earlier diagnosis and treatment of conditions including reflux disease, colon cancer, and inflammatory bowel disease.

Using a tiny microscope at the tip of an endoscope to provide highly magnified images, CLE allows for expanded diagnostic possibilities during endoscopy, which can help detect suspicious activity immediately. A study showed that doctors are now able to identify the same amount of precancerous cells using images from confocal laser CLE, as would have been found using traditional biopsy. This finding could reduce the number of biopsies taken because doctors using CLE would know whether precancerous cells existed, and therefore would not have to needlessly biopsy tissue that may not be abnormal.

Investigators used CLE to examine patients with Barrett's esophagus (BE), a condition that can often lead to esophageal cancer, in an effort to detect tiny precancerous lesions before they grow. One challenge with BE is that it can require several tissue biopsies, which are expensive, invasive, and can cause bleeding. Using CLE, researchers were able to magnify the lining of the esophagus 1,000 times, which enabled investigators to take biopsies only of areas that looked suspicious, instead of performing many unnecessary random biopsies.

"Up until now, determining the condition of a patient required days or even weeks while patients waited for a diagnosis; further, it has been difficult to detect subtle precancerous lesions or even areas within a larger lesion, often leading to time-consuming and labor-intensive procedures as well as uncertainty about missing something important,” said Pankaj J. Pasricha, M.D., FASGE, professor of medicine, gastroenterology, and hepatology, Stanford University School of Medicine (Stanford, CA, USA).

The confocal endomicroscopy system (CFM) can immediately distinguish benign from precancerous polyps of the colon with very high accuracy. The procedure allows clinicians to both diagnose and treat the condition at the time of the procedure, and it prevents unnecessary biopsies and removal of tissue.

Investigators used a catheter probe-based CFM system, which can be passed through the accessory channel of almost any endoscope. The CFM probe provides images of cells and the tiny blood vessels around the cells, similar to what pathologists look at under a standard microscope. The investigators performed the procedure on 26 patients in two phases.

First, they removed the polyps and waited for pathological results. Then they looked at the images to determine which cells appear abnormal and normal. They found that using CFM, they could predict the sensitivity and specificity of the polyps with 89% accuracy. Furthermore, investigators looked at small polyps that appeared to be benign that would normally have been removed. Using CFM, they were able to accurately detect that they were benign 98% of the time.

"This technique will fundamentally change how the two fields interact,” said Anna M. Buchner, M.D., Ph.D., from the Mayo Clinic (Jacksonville, FL, USA). "This procedure allows us to become endopathologists, and the result is that we will be able to better manage patients with gastrointestinal disorders.”

These findings were presented at Digestive Disease Week 2008, which took place on May 17-22, 2008, in San Diego (CA, USA).


Related Links:
Stanford University School of Medicine
Mayo Clinic