Visual Oral Examination for Early Detection of Oral Cancer in High-Risk Individuals
Condition: Mouth Neoplasms
MeSH terms: Mouth Neoplasms
Study type: Interventional

Summary: 
      Oral cancer (OC) is a public health problem in Brazil, with high morbidity and mortality,
      mainly associated with late diagnosis, which implies high-cost treatments and great social
      impact, with aesthetic and functional sequelae. Smokers and alcoholics are at increased risk
      for the disease, being early detection the most effective way to increase survival. In
      Brazil, cancer plan recommends early diagnosis of OC through opportunistic examination, which
      is carried out during regular visits to the dentist. However, this strategy has not yet been
      able to reverse the late diagnosis, which may be due to the low access to dental appointments
      by the most vulnerable groups. Studies point to the effectiveness of the preventive physical
      examination of the mouth for early detection when directed to the high-risk population. The
      aim of the present study is to compare different strategies aimed at expanding the access of
      the high-risk population to preventive physical examination of the mouth. A
      cluster-randomized trial (control group and experimental groups I and II) will be carried out
      in Primary Health Care units in Programmatic Area 5.2 of the city of Rio de Janeiro (eight
      neighborhoods in the West Zone).

      In the control group, there will be no change in current care. In both experimental groups,
      Community Agents and health professionals will be trained in OC prevention and instructed to
      call the users with high-risk for OC to the preventive examination of the mouth at the health
      unit. After 6 months, in experimental group I, an active search will be carried out for users
      who did not show up for the preventive examination, while in experimental group II, a
      campaign on OC will be carried out for a month, inviting the population to the preventive
      examination. After one year, the number of people at increased risk for OC examined in each
      group will be compared and correlated with sociodemographic and clinicopathological
      variables.
    

Detailed description: 
      Oral cancer (OC) is a significant public health concern in Brazil, with the country having
      the highest incidence of the disease in Latin America. It ranks as the fourth most common
      cancer among men in the southeast region. This condition carries substantial morbidity and
      mortality, largely due to the majority of patients being diagnosed at advanced stages,
      leading to elevated treatment costs, prolonged rehabilitation, and profound social impacts
      such as loss of labor capacity and exclusion from social environments.

      Squamous cell carcinoma, constituting 90 to 95% of OC cases, primarily affects men over 50
      years old, with an emerging incidence in individuals under 40. In Brazil, the lateral border
      of the tongue is the primary site, characterized by invasive growth, significant recurrence
      rates, and metastasis to regional lymph nodes.

      The main etiological factors for OC include tobacco and alcohol for intraoral lesions,
      prolonged exposure to ultraviolet (UV) radiation for lip cancer, and, for oropharyngeal
      cancer, human papillomavirus (HPV) infection. Cultural characteristics, socioeconomic level,
      and access to public health services also contribute to the variation in oral cancer
      incidence.

      Primary prevention is paramount and involves educating individuals on behavioral risk
      factors, limiting tobacco and alcohol use, sun protection for the lips, HPV vaccination for
      oropharyngeal cancer prevention, and maintaining a healthy diet. Secondary prevention focuses
      on early disease through detection for pre-clinical signs and early diagnosis for individuals
      exhibiting suspected symptoms.

      The justification for implementing a population screening program as a public health policy
      is based on established criteria. While OC meets ten out of the 19 criteria presented at the
      Global Oral Cancer Forum in 2016, its cost-effectiveness remains unproven, unlike breast and
      cervical cancer, which have well-defined population screening protocols.

      Although a clinical trial in Kerala, India, did not demonstrate reduced OC mortality through
      population monitoring, a reanalysis in 2021 highlighted the effectiveness of targeted
      preventive mouth examinations by trained health professionals for at-risk populations.

      In many countries, including Brazil, opportunistic examinations of the mouth's soft tissues
      are recommended for early diagnosis of lesions, but the majority of oral cancer cases are
      still diagnosed at advanced stages. The National Oral Health Policy, established in 2004,
      aims to promote, prevent, recover, and maintain oral health through primary care and
      specialized dental centers.

      Recognizing structural and social determinants is crucial for effective prevention,
      detection, and management of OC. The "inverse screening law" highlights challenges in
      opportunistic examinations, and barriers to accessibility and diagnostic delays persist,
      especially among the elderly.

      Despite the current strategy in Brazil relying on opportunistic testing, the majority of OC
      cases are diagnosed late. Weaknesses in the city of Rio de Janeiro, including low population
      coverage in Oral Health in Primary Care and limited access for at-risk populations,
      underscore the likely ineffectiveness of the current preventive strategy.

      The present study is justified by the imperative to expand access to preventive oral
      examinations for individuals at increased risk for OC, aiming for early diagnosis and
      subsequently reducing mortality and morbidity.
    

Intervention name(s): Visual oral examination
Intervention type(s): Diagnostic Test
Intervention description(s): Oral preventive examinations in the three groups will be conducted over a one-year period. Individuals with oral injuries will be referred to stomatology, aligning with the existing protocol. Histopathological examinations of the biopsied lesions will be performed at the Oral Pathology Laboratory of the Faculty of Dentistry at the Federal University of Rio de Janeiro, following the established procedures.
Users diagnosed with malignancy will be directed to receive treatment at the reference hospital, with monitoring carried out by the Basic Health Unit responsible for coordinating care, in accordance with the current protocol.
In addition to histopathological examinations, the Faculty of Dentistry will be available to conduct a physical examination and biopsy if the user is not attended to by the Municipal Health Department. This additional resource ensures comprehensive care for individuals who may not have immediate access to municipal health services.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: cluster randomized clinical trial
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Mouth Neoplasms; early diagnosis; public health; prevention