Derivation and validation of a risk-factor model for detection of oral potentially malignant disorders in populations with high prevalence.
BACKGROUND
Oral and pharyngeal cancers constitute the sixth most common type of cancer globally, with high morbidity and mortality. In many countries, most cases of oral cancer arise from long-standing, pre-existing lesions, yet advanced malignancies prevail. A new approach to early detection is needed. We aimed to validate a model for screening so that only high-risk individuals receive the clinical examination.


METHODS
A community-based case-control study (n=1029) in rural Sri Lanka assessed risk factors and markers for oral potentially malignant disorders (OPMD) by administering a questionnaire followed by an oral examination. We then developed a model based on age, socioeconomic status and habits of betel-quid chewing, alcohol drinking and tobacco smoking, with weightings based on odds ratios from the multiple logistic regression. A total, single score was calculated per individual. Standard receiver-operator characteristic curves were plotted for the total score and presence of OPMD. The model was validated on a new sample of 410 subjects in a different community.


RESULTS
A score of 12.0 produced optimal sensitivity (95.5%), specificity (75.9%), false-positive rate (24.0%), false-negative rate (4.5%), positive predictive value (35.9%) and negative predictive value (99.2%).


CONCLUSIONS
This model is suitable for detection of OPMD and oral cancer in high-risk communities, for example, in Asia, the Pacific and the global diaspora therefrom. A combined risk-factor score of 12.0 was optimal for participation in oral cancer/OPMD screening in Sri Lanka. The model, or local adaptations, should have wide applicability.
Amarasinghe
H K
HK
Dental Institute, Maharagama, Colombo 10280, Sri Lanka. hemanthaamarasinghe@yahoo.com
Johnson
N W
NW
Lalloo
R
R
Kumaraarachchi
M
M
Warnakulasuriya
S
S
D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects; D001114:Areca / Q000009:adverse effects; D006801:Humans; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000175:diagnosis* / Q000453:epidemiology* / Q000517:prevention & control; D016017:Odds Ratio; D010610:Pharyngeal Neoplasms / Q000453:epidemiology* / Q000517:prevention & control; D015995:Prevalence; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology; D012959:Socioeconomic Factors; D013188:Sri Lanka / Q000453:epidemiology; D011795:Surveys and Questionnaires