Historically, it has been difficult to determine which abnormal tissues in the mouth are worthy of concern. The fact is, the average person routinely has conditions existing in their mouths that mimic the appearance of pre-cancerous changes, and very early cancers of the soft tissues. One study determined that the average dentist sees 3-5 patients a day who exhibit soft tissue abnormalities, most of which are benign in nature. Even the simplest things, such as a canker sore (herpes simplex), the wound left by accidentally biting the inside of your cheek, or sore spots from a poorly fitting prosthetic appliance or denture, all at first examination, share similarities with dangerous lesions. Some of these conditions cause physical discomfort, others are painless. The question is which ones deserve action, and which ones bear watching and waiting?
There has been a tendency to watch these areas over an extended period to determine if they are dangerous or not. Unfortunately, this philosophy leads to a situation in which a dangerous lesion may continue to prosper and grow into a later stage, hard to cure cancer. Any sore, discoloration, induration, prominent tissue, irritation, hoarseness, which does not resolve within a two week period on its own, with or without treatment, should be considered suspect and worthy of further examination or referral. Besides a routine visit to the dental office for regular examinations, it is the patient's responsibility to be aware of changes in their oral environment. When these changes occur, they need to be brought to the attention of a qualified dental professional for examination. The dental professional needs to be current in the knowledge base necessary to make a proper diagnosis, and be competent in the proper screening procedures to identify oral cancer.
Discovery and Diagnosis
There are two separate issues, discovery and diagnosis. Discovery is the result of a thorough visual and manual examination. It includes a systematic visual examination of all the soft tissues of the mouth, including manual extension of the tongue to examine its base, a bi-manual palpation of the floor of the mouth, and a digital examination of the borders of the tongue, and the lymph nodes surrounding the oral cavity and in the neck. New diagnostic aids, including lights, dyes, and other techniques are beginning to appear on the marketplace. While making the discovery process more effective, it is still possible to do a comprehensive examination through a proper visual and tactile process.
Once suspect tissues have been detected, the only way a definitive diagnosis of oral cancer may be made is through biopsy. Given the large number of tissue abnormalities a dentist sees every day, it is not logical, nor practical, that each one of these be biopsied. The first question which may help in the determination of which abnormality bears closer examination, is how long has the suspect condition been present? Any condition that has existed for 14 days or more without resolution should be considered suspect and worthy of further diagnostic procedures or referral. Certainly, it is common knowledge that two of the most prevalent lesions that mimic oral cancer, are the herpes simplex ulceration, and aphthous ulcerations, each resolving of their own accord in approximately 10-14 days.
Another new way to test for oral cancer before incisional biopsy is beginning to be used by dental professionals -- brush cytology. Here, a dentist uses a small brush to gather cell samples of a suspicious area. The specimen is then sent to a lab for analysis.
This oral brush biopsy procedure is simple, and can be done right in the dentist's chair. It results in very little or no pain or bleeding, and requires no topical or local anesthetic. Firm pressure with a circular brush is applied to the suspicious area. The brush is then rotated five to ten times, causing some pinpoint bleeding or light abrasion. The cellular material picked up by the brush is transferred to a glass slide, preserved, and dried. The slide is then mailed to a laboratory along with written documentation about the patient and a detailed description of the questionable area of the mouth. At the laboratory, they will examine the sample for cells which show signs of change, such as dysplasia or full malignancy. A pathologist examines the cells to determine the final diagnosis. A negative result of course, confirms that the cells are benign. In samples that are judged to be cancerous, either way a written pathologist's report are returned to the dentist. It is usually recommended that a positive result be followed with a conventional incisional biopsy. This is because the sample type taken by the brush technique does not provide the cells in any relationship to each other. In order to properly now determine the extent of the cancer, a sample which also provides the architecture, or the actual relationship of the different layers of cells to each other is necessary. The benefits of brush cytology are the possible avoidance of surgical biopsy, and the ease of sampling, which can be performed during a routine dental examination. Because of its ease of use, and the elimination of any surgical procedure, no matter how small, this method allows tissue samples to be taken early in the process of areas that in the past, the doctor may have decided to just watch for while. With oral cancer, an earlier determination is always important, for both your piece of mind, and because cancers caught earlier have a higher success rate of being cured.
Should positive results be returned through this system, the brush biopsy must be followed by a conventional biopsy procedure for confirmation. The strong argument for the brush biopsy is that it eliminates the waiting and watching of a suspicious lesion, while it develops from a highly treatable and curable, early stage localized cancer, into a life threatening late stage malignancy. Positive identification of oral cancers at the earliest stages, result in the best prognosis for cure and long-term survivability.
Creating awareness, discovery, diagnosis, and referral. When it comes to oral cancer and saving lives, these are the primary responsibilities of the dental community. The most important step in reducing the death rate from oral cancer is early discovery. No group has a better opportunity to have an impact than members of the dental community.