July/August 2011, Volume 7, Issue 7
Published by AEGIS Communications
Oral Cancer Detection Equipment
There has been more change in the arena of in-office early detection of oral cancers and precancers in the past decade than in the entire previous history of dentistry. In particular, new light technologies, such as loss of autofluorescence, VELscope VX (LED Dental, www.velscope.com) and Identafi® (DentalEZ Group, www.identafi.net), are now providing dentists with logical and scientifically sound techniques, as are cytology-based DNA imaging tests, such as OralAdvance™ (Perceptronix, www.oraladvance.com). These technologies have been developed for the medical profession, and while dentistry is certainly having “growing pains” adapting them to the oral environment, dentists are rapidly determining their limitations, potentials, and value.
Additionally, the phenomenally dynamic and interdependent fields of salivary proteomics and “lab-on-a-chip” nanotechnology are on the verge of becoming the “next big thing” for identifying which mucosal changes are the most dangerous; they have the added advantage of potentially identifying or even diagnosing serious systemic disorders such as breast cancer and diabetes. These and other already available technologies, such as the OraRisk® HPV Salivary Diagnostic Test (OralDNA® Labs, www.oraldna.com) can also be used to help assess oral cancer risk factors in patients with suspicious lesions, or no lesions at all, just as knowledge of tobacco and alcohol use helps clinicians today.
The impact is clear: dentists now have the wherewithal to actually apply evidence-based dentistry to the field of oral cancer screening and early detection in the office. While there will probably never come a time when these adjunctive tests can be used as stand-alone identifiers of dangerous oral mucosa, when their results are intelligently added to all the clinical and historical features of a lesion, the increase in the clinician’s acumen can be remarkable.
Like the cone beam CT scan, a wealth of heretofore unavailable diagnostic information becomes accessible with new dysplasia detection devices, but dentists are still obligated to be doctors, not technicians. Very seldom do new devices come along that reduce our need to be critical thinkers. In my long professional career, I have seen just the opposite; with new technologies come new responsibilities and a need for expanded training and clinical decision-making.
Today, the literature is robust with information on new technology, which is distinctly different from earlier technologies that were promoted with little or no evidence base. While none of the new technologies are yet standard of care, loss of autofluorescence, DNA ploidy change, and identification of HPV subtypes 16 or 18 in saliva or biopsied tissue samples have numerous peer-reviewed papers to support their use in a conscientious practice.
As an oral pathologist with a long, strong interest in and extensive clinical experience with oral precancers, I would feel lost without at least an autofluorescence device when evaluating potentially malignant lesions. The new or adjunctive information provided is sometimes confusing, but combined with a thorough knowledge of the well-established clinical features associated with increased cancer transformation risk, it is a vast improvement over clinical examination alone.
There are certainly some who say that the level of false positives adds an unreasonable burden of risk for biopsy trauma and psychological stress from the wait for the biopsy report. I personally have had few false positives, but am thoroughly convinced that the benefits of this technology far outweigh the disadvantages.
My expertise and experience makes me different from a general practitioner regarding oral cancer “screenings,” and none of the new technologies have proven cost-effective in a public health sense. However, my practice philosophy has always been one of attempting (sometimes even succeeding) to provide “first class” dental care for my patients; simply meeting the standard of care is not enough.
Were I a family dentist today, I would use autofluorescence annually as a screening device and more frequently as a follow-up tool, but I would never, ever think of this as my only screening tool. I would always remain vigilant for those unavoidable false positives and false negatives. I would depend on its additional information to help my decision-making (including referral) about any unusual entities found on the oral mucosa.
I see no reason why the dental hygienist cannot add autofluorescence to her or his armamentarium, calling the dentist’s attention to any abnormalities or areas where the normal fluorescence is severely lost. The use of this particular technology has a learning curve associated with it, but once the clinician/hygienist becomes familiar with the “different shades of gray” and the non-neoplastic lesions that also show a loss of autofluorescence, the office will become as dependent on the technologies as so many specialists are today.
That said, I am convinced that autofluorescence is not a tool for lazy thinkers, and the obligation to read, read, read the literature is much more important than it used to be. There is so much worthy information so readily available today that there is no excuse for not knowing both the pitfalls and advantages of new technologies. This can be confusing, because there seems to be a “con” paper published for every “pro,” and without a strong background in a subject, one may not see the inherent biases in some published papers. The obligation remains, nevertheless. It’s part of being a doctor.
About the Author
J.E. Bouquot, DDS
Professor & Chair
Department of Diagnostic Sciences
University of Texas Dental Branch at Houston