Screening for oral cancers

In 2017, it was estimated that there would be approximately 49,670 new cases of oral cavity and oropharyngeal cancers, and 9,700 deaths from the disease per year.1 Survival rates range from 83.7% when the cancer is localized, to 64.2% and 38.5% when regional and distant metastases are diagnosed. Sadly, about 70% of all new cases are diagnosed at a later stage, which indicates the need for early detection of oral cancer.1

A conventional visual and tactile examination (CVTE) intraorally and extraorally, along with a full review of a patient’s health history including medical, social, and dental information, is needed to identify abnormalities and risks for oral cancers.

Although this examination is a standard procedure, many adjuncts exist to screen patients as well. These adjuncts have been used for triage, to replace the CVTE, or as add-ons to help identify potentially malignant disorders and oral squamous cell carcinomas in the oral cavity. While there are many screening adjuncts available, often marketed as devices that can help “save a life,” the efficacy of these products has not been adequately established.

In 2017, the ADA Council on Scientific Affairs convened an expert panel of general dentists, oral medicine specialists, otolaryngologists, oncologists, oral and maxillofacial pathologists and surgeons, epidemiologists, and a dental hygienist (me) to conduct a systematic review of the scientific literature, and to examine the evidence related to the diagnostic accuracy of these adjuncts as triage tools.

Multiple outcomes were considered in terms of diagnostic test accuracy, including sensitivity, specificity, likelihood ratios, confidence intervals, true positive, false positive, true negative, and false negative. Other outcomes included oral cancer mortality, survival, unnecessary biopsy, quality of life, all-cause mortality, incidence of oral cancer, anxiety and stress, costs, and patient values and preferences. The result was the development of updated clinical recommendations and practice guidelines for primary care clinicians to use when examining patients in various clinical settings, including dental hygiene practice.2

A summary of the findings of the expert panel are accessible through the Center for Evidence-Based Dentistry.3 In addition to the findings, the Center provides access to the clinical recommendations, a chairside guide, materials for patients, and an instructional video. A chairside guide was created to assist practitioners in having a ready reference of the recommendations based on the findings of the expert panel and can be found at JADA.ADA.org. These recommendations are provided with a grade or assessment based on the quality of the evidence (high, moderate, low, or very low). This is influenced by factors such as risk of bias, imprecision, inconsistency, and publication bias. In addition, the strength of the recommendations is either strong or conditional.

When you read these recommendations, note that the expert panel did not recommend the use of most screening adjuncts. The strength of the evidence was low to very low for most of these devices, largely as a result of the tendency toward the high number of false positives. However, it would be helpful to read the entire report to understand the scope of the findings. So, what do we do to assist patients when we see innocuous lesions or suspect a potentially malignant disorder? “A Chairside Guide: Clinical Pathway for the Evaluation of Potentially Malignant Disorders in the Oral Cavity” can be found on the ADA website.

Does this mean we throw away our screening tools and stop looking for oral cancer? No! It is absolutely essential that we examine each patient at every appointment for risks and symptoms of oral cancers. The expert panel recommends we update health histories and perform CVTEs routinely. If there are no clinically evident lesions or symptoms, no further action is needed at that time.

However, if there is clinical evidence of any oral mucosal lesion considered suspicious of a potentially malignant disorder, then the lesion should be biopsied or the patient referred immediately to a specialist. In some cases, when a patient declines a biopsy or referral for further evaluation, a cytology adjunct can be used as a triage tool to provide additional lesion assessment and assist with clinical decisions.2

As oral health professionals, dental hygienists have the opportunity to educate patients about oral cancers and the preventive measures available, including regular CVTE and self-examination. They will appreciate the partnership we convey in wanting to promote early detection and save lives.

Joann R. Gurenlian, RDH, PhD, is president of Gurenlian & Associates, and provides consulting services and continuing education programs to health-care providers. She is a professor and dental hygiene graduate program director at Idaho State University, and past president of the International Federation of Dental Hygienists.

References

1. Siegel RL, Miller KD, Jemal A. Cancer statistics, 2017. CA Cancer J Clin. 2017;67(1):7-30.

2. Lingen MW, Abt E, Agrawal N, Chaturvedi AK, Cohen E, et al. Evidence-based clinical practice guideline for the evaluation of potentially malignant disorders in the oral cavity. JADA. 2017;148(10):712-727.

3. Center for Evidence-Based Dentistry. Evaluation of Potentially Malignant Disorders in the Oral Cavity Clinical Practice Guideline (2017). EBD.ADA website. http://ebd.ada.org/en/evidence/guidelines/oral-cancer?source=promospots&content=OralCancerGuidelines&medium=Panel&campaign=Best Evaluation of Potentially Malignant Disorders in the Oral Cavity Clinical Practice Guideline (2017). Accessed October 16, 2017.