Diagnostics & Imaging Week Contributing Writer
SAN DIEGO — Nearly 16,000 physicians, researchers and academics from around the world gathered here in mid-May under brilliantly sunny skies and record-breaking warm temperatures to attend the 2008 Digestive Disease Week 2008, the largest conference of its kind.
Advances in micro-technology have expanded the options available for endoscopists to treat, in addition to diagnose, certain alimentary tract diseases in an even less-invasive manner than laparoscopy, a minimally invasive technique usually performed by surgeons.
Many innovative products were showcased here, from the latest advances in colon cancer surveillance and treatment to novel endoluminal techniques for obesity and GERD, all of which access the gastrointestinal tract through an endoscope.
Standard goals for new medical technologies are to provide for better patient care and/or reduce cost, both of which are captured with Confocal Laser Endomicroscopy (CLE). This new real-time microscopic technique may eventually lead to skipping the entire step of sending biopsies to pathology and could change the way gastrointestinal diseases are detected.
CLE, a technology currently FDA-cleared and marketed by Pentax Medical (Montvale, New Jersey) and Mauna Kea Technologies (Paris), places a tiny microscope at the tip of an endoscope that magnifies the image by 1000 times, helping endoscopists to determine on-the-spot whether a lesion is suspicious, or even cancerous, or not.
While the Pentax Medical system has the microscope incorporated into the endoscope, Mauna Kea's Cellvizio system — which has completed more than 1,000 procedures to date — allows its miniaturized microscope to be threaded through all endoscopes.
At that magnification, the resolution is almost as reliable as a pathologic sample, and may eliminate the need for biopsy to diagnose gastrointestinal conditions including reflux disease, colon cancer, and inflammatory bowel disease.
"Up until now, patients waited days or weeks for a diagnosis; further, it has been difficult to detect subtle precancerous lesions, often leading to time-consuming procedures as well as uncertainty about missing something important" said Pankaj Pasricha, MD, professor of medicine, gastroenterology and hepatology at Stanford University School of Medicine (Stanford, California). "New techniques such as CLE will change the way we diagnose patients, allowing us to treat them more accurately, quickly and appropriately."
Kerry Dunbar, MD, of the department of medicine-gastroenterology at the Johns Hopkins Medical Institutions (Nantes, France), has performed 2,102 CLE examinations and found that the overall accuracy rate for CLE was 91% in the upper GI tract and 93% in the lower tract. "This has the potential to help patients more quickly," said Dunbar, adding that given the rapid progression of cancers, earlier detection and treatment is critical.
In her study, she found that 20% to 30% of the cases would have had a changed diagnosis using CLE. At this point, biopsies are still taken and sent to the lab, but in the future with more experience with CLE, it will be possible to be able to immediately diagnose and treat, eliminating the weeklong trip the specimen takes to the pathology lab.
With that as the great promise for the future, today's advantage is that the number of biopsies taken per CLE examination are significantly reduced, offering a cost savings for pathology exams and a reduction in time the patient is under sedation-another savings in cost as well as providing better patient care.
In another collaborative study reported on by Dunbar, CLE was used to diagnose patients with Barrett's esophagus, a disease in which dysplasias are difficult to see with an endoscope. "We were able to take 60% fewer biopsies and still detect the same amount of cancers," she said. "We were able to better target our lesions and could take five biopsies instead of 20, realizing a tremendous cost and time saving without sacrificing accuracy.
Another CLE researcher who presented at DDW, Michael Wallace, MD, of the Mayo Clinic (Jacksonville, Florida), found that, "The probe-based confocal microendoscopy system allows immediate diagnosis of colorectal lesions with malignant potential and can distinguish them from non-neoplastic polyps with a high level of accuracy." He also noted that this method has the potential of obviating polypectomy of non-neoplastic polyps.
With these positive early reports and only two players, it is safe to assume that there will be new entries in this market in the near future.
Yet another interesting diagnostic technology is that of capsule endoscopy, introduced by Given Imaging (Yokneam, Israel) in 2001 and now boasting more than 730,000 PillCam video capsules having been sold.
The PillCam video capsule is a disposable, miniature video camera contained in a capsule that can be easily ingested by the patient and whose images are then captured and stored in a belt worn around the patient's waist for eight hours.
The capsule transmits high-quality color images of the gastrointestinal (GI) tract, enabling physicians to visualize distinct portions of the tract.
Given's first product, cleared by the FDA in 2001, captured images of the small intestine, followed by the clearance of the esophageal PillCam in 2004, and the PillCam Colon that already has its CE-mark will be FDA-cleared for use in the U.S. next.
Swallowing a pill is much easier for many patients who cannot or will not have an endoscope placed in their GI tract, or who cannot undergo the sedation required for endoscopic procedures.
In addition to ease of use for the patient, the PillCam also is the only non-invasive device able to visualize the entire small bowel mucosa, previously visible only by surgery.
The results of an eight-center European study presented here by Jacques Deviere, MD, of Erasme Hospital (Brussels, Belgium), demonstrated encouraging results for detecting colo-rectal polyps compared to colonoscopy.
"The promise of PillCam Colon is increasing the number of colo-rectal screenings, which remain disappointingly low in Europe," he said. "This patient-friendly alternative could become a key tool in the effort to reduce the more than 212,000 colo-rectal cancer deaths annually in Europe."
Deviere added, "Patients who can't or are unwilling to undergo a colonoscopy have a new way to be screened in a very easy, painless way. If polyps or cancerous lesions are found, then the physician can perform a subsequent procedure to remove the lesions."
He said the initial data on PillCam Colon is "extremely promising, and we look forward to additional clinical information to determine how best to use this valuable diagnostic tool."
DDW is jointly sponsored by the American Association for the Study of Liver Diseases (AASLD; Alexandria, Virginia), the American Gastroenterological Association (AGA; Bethesda, Maryland), the American Society for Gastrointestinal Endoscopy (ASGE; Oak Brook, Illinois) and the Society for Surgery of the Alimentary Tract (SSAT; Beverly, Massachusetts).