Visual Oral Examination for Early Detection of Oral Cancer in High-Risk Individuals

May 1, 2026 updated by: Marcia Frias Pinto Marinho, Universidade Federal do Rio de Janeiro

Visual Oral Examination in Primary Health Care for Early Detection of Oral Cancer: Targeting High-Risk Individuals in the Municipality of Rio de Janeiro

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.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

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.

Study Type

Interventional

Enrollment (Actual)

1152

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Brazil
    • Rio de Janeiro
      • Rio de Janeiro, Rio de Janeiro, Brazil, 23070-220
        • Health Units of the Municipality of Rio de Janeiro

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Individuals who are regular smokers and/or chronic alcohol users
  • Individuals registered as patients at Family Clinics within Programmatic Area 5.2 in the city of Rio de Janeiro
  • Individuals aged 35 years or older

Exclusion Criteria:

  • Individuals who have had a regular dental visit within the last 12 months

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
No Intervention: Control Group
Health professionals, including dentists (CD), dental hygienists (TSB), dental assistants (ASB), nurses, and general practitioners, will continue providing care to users in accordance with the existing Service Card protocols in the city of Rio de Janeiro. This ensures on-demand service for users seeking dental care. Additionally, they will continue to facilitate participation in the Tobacco Control Program for interested individuals, following the established protocol of the city of Rio de Janeiro. Notably, members of the control group will not partake in the qualification process conducted by this research project. However, in the event of positive results at the research's conclusion, consideration will be given to extending qualification opportunities to the control group as well.
Experimental: Active Screening Group

Health professionals (Community Health Agents, dentists, dental hygienists, dental assistants, nurses, and general practitioners) will undergo training focused on preventing OC, considering risk factors and highlighting the significance of preventive oral examinations for early diagnosis. Dentist and general practitioners will receive training to conduct oral examinations, enabling them to identify suspicious lesions and potentially malignant disorders. The qualification process will be conducted through face-to-face meetings and/or videoconferencing, supplemented by educational material delivered via the widely used messaging application (WhatsApp).

Following qualification, tobacco users and excessive alcohol users will be invited to visit the Family Clinic for oral preventive examination. After six months, in the event that a user does not attend the Family Clinic, the Health Team will conduct an active search, through home visits or community outreach in bars.
Diagnostic test: Visual oral examination

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.
Experimental: Campaign Group

Health professionals (Community Health Agents, dentists, dental hygienists, dental assistants, nurses, and general practitioners) will be training focused on preventing OC, risk factors and highlighting the significance of preventive oral examinations for early diagnosis. Dentist and general practitioners will receive training to conduct oral examinations, enabling them to identify suspicious lesions and potentially malignant disorders. The qualification process will be conducted through face-to-face meetings or videoconferencing.

Following qualification, tobacco and excessive alcohol users will be invited to visit the Family Clinic for oral examination. After six months, a public awareness campaign, over one month, will be conducted in the Family Clinics. This campaign will provide guidance on risk factors, signs and symptoms, and the importance of oral examinations.
Diagnostic test: Visual oral examination

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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of Preventive Oral Examinations among Individuals Aged 35 and Older, Smokers, and/or Alcohol Drinkers within One Year Post-Implementation of Strategies in Experimental Groups
Time Frame: one year
The descriptive characterization of the sample will be estimated for both the control and experimental groups, encompassing the absolute and relative counts of individuals aged 35 and older, smokers, and/or alcohol drinkers who underwent a preventive oral examination within one year following the implementation of strategies in the experimental groups.
one year

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Universidade Federal do Rio de Janeiro

Collaborators

Conselho Nacional de Desenvolvimento Científico e Tecnológico
Rio de Janeiro State Research Supporting Foundation (FAPERJ)

Investigators

  • Principal Investigator: Marcia F Marinho, MSc, Universidade Federal do Rio de Janeiro

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 1, 2023

Primary Completion (Actual)

December 31, 2023

Study Completion (Actual)

January 10, 2024

Study Registration Dates

First Submitted

January 12, 2024

First Submitted That Met QC Criteria

January 26, 2024

First Posted (Actual)

January 30, 2024

Study Record Updates

Last Update Posted (Actual)

May 7, 2026

Last Update Submitted That Met QC Criteria

May 1, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • O/OC 2023-2024

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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