Oral cancer screening programmes.

Data Sources: The Cochrane Oral Health Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase and CANCERLIT.

Study Selection: Randomised controlled trials (RCTs) of screening for oral cancer or potentially malignant disorders using visual examination, toluidine blue, fluorescence imaging or brush biopsy were included. There were no restrictions regarding language or date of publication.

Data Extraction And Synthesis: The original review identified 1,389 citations and this update identified an additional 330 studies. Validity assessment, data extraction and statistics evaluation were undertaken by six independent review authors.

Results: Only one 9-year cluster RCT was included (n = 13 clusters: 191,873 participants). No statistically significant differences in the age-standardised oral cancer mortality rates for the screened group (16.4/100,000 person-years) and the control group (20.7/100,000 person-years) were identified. A 43% reduction in mortality was reported between the intervention cohort (29.9/100,000 person-years) and the control arm (45.4/100,000) for high-risk individuals who used tobacco or alcohol or both, which was statistically significant. However, this study had a number of methodological weaknesses and the associated risk of bias was high.

Conclusions: Although there is evidence that a visual examination as part of a population-based screening programme reduced the mortality rate of oral cancer in high-risk individuals, whilst producing a stage shift and improvement in survival rates across the population as a whole, the evidence is limited to one study and is associated with a high risk of bias. This was compounded by the fact that the effect of cluster randomisation was not accounted for in the analysis. Furthermore, no robust evidence was identified to support the use of other adjunctive technologies like toluidine blue, brush biopsy or fluorescence imaging within a primary care environment. Further RCTs are recommended to assess the efficacy, effectiveness and cost-effectiveness of a visual examination as part of a population based screening programme.