NO EVIDENCE FOR ORAL CANCER SCREENING

The evidence is insufficient to assess the balance of benefits and harms of screening by primary care providers for oral cancer in asymptomatic adults, according to updated guidelines from Virginia A. Moyer, MD, MPH, on behalf of the US Preventive Services Task Force (USPSTF). The guidelines will be published online November 26 in the Annals of Internal Medicine.

"According to National Cancer Institute data, the estimated new cases and deaths from oral cancer (oral cavity and pharynx) in the United States in 2013 is 41,380 new cases and 7890 related deaths," Dipika Bumb, BDS, MDS, an oral oncologist and tobacco control officer at the Indian Cancer Society in New Delhi, India, told Medscape Medical News when asked for independent comment. "The burden of disease is not less."

Squamous cell carcinoma accounts for 90% of all cases of oral cavity and pharyngeal cancer. More than half of persons with oral and pharyngeal cancer have regional or distant metastases when they are first diagnosed. The USPSTF therefore stated that screening for oral cancer may be helpful if potentially malignant disorders can be identified earlier and treated successfully.

"In clinical practice, screening can help in detection of oral cancer at a very early stage, where the lesions are either reversible or can be treated efficiently," Dr. Bumb said. "The changes occur at a slower pace in oral mucosa, [but the need for] oral cancer screening lacks recognition all over the world. Awareness among the medical community and government is the need of the hour."

USPSTF Deems Evidence to Be Insufficient

The revised guidelines, which update the 2004 USPSTF recommendation on screening for oral cancer, apply to screening of the oral cavity performed by primary care providers, and not by dental providers or otolaryngologists. The USPSTF reviewed the evidence both on whether screening for oral cancer was associated with lower morbidity or mortality and on the accuracy of the oral screening examination to detect oral cancer or potentially malignant disorders that are highly likely to progress to oral cancer.

On the basis of this evidence review, the USPSTF concluded that the current evidence was insufficient to evaluate the balance of benefits and harms of screening for oral cancer in asymptomatic adults aged 18 years or older who are seen by primary care providers. This is an I-level statement.

However, the USPSTF recognizes that clinical decisions, as well as policy and coverage decisions, involve more considerations than evidence of clinical benefits and harms alone. Therefore, clinicians should individualize decision making to the specific patient or situation.

"Potentially malignant disorders can be detected by visual examination by trained clinicians," Dr. Bumb said."The agony of the situation is that clinicians don't realize this, leading to late diagnosis and referral. During screening, the habit of tobacco and alcohol use can be regulated by professional counseling, leading to reduction in risk for other noncommunicable diseases."

The USPSTF found inadequate evidence that the oral screening examination accurately detects oral cancer or that screening for oral cancer and treatment of screen-detected oral cancer reduces morbidity or mortality. Furthermore, they found inadequate evidence on the harms of screening, as no study reported on harms from the screening test, from false-negative results, or from false-positive results leading to unnecessary surgery, radiation, and chemotherapy.

Because the natural history of screen-detected oral cancer or potentially malignant disorders is unclear, the degree of overdiagnosis resulting from screening is unknown.

Potential Harms of Not Screening

If practitioners stop screening for oral cancer, Dr. Bumb is concerned about the following potential consequences:

• Abandoning screening could substantially increase the incidence of oral cancer and other tobacco/alcohol/HPV-related disorders in the young population.
• Tobacco and alcohol cessation could become difficult, with interrelated addiction leading to further deterioration of health.
• Treatment of oral cancer not detected until late in the course results in disfigurement and disability of the face and neck.
• Treatment of oral cancer not detected until late in the course hinders delivery of palliative care and harms the individual's psychological integrity.

"In developing countries like India, oral cancer accounts for 95% of all cancers, and screening serves as the best tool in reduction of mortality and morbidity," Dr. Bumb said. "Like breast lumps are helpful in detection of breast cancer at an early stage, similarly, oral potentially malignant disorders (OPMD) are a stepping stone towards development of oral cancer."