Interventions for oral cancer prevention: An evidence and gap map

Oral cancer is the 16th most common cancer globally, but oral cancer prevention is limited. We developed five evidence and gap maps using 188 studies identified in the International Agency for Research on Cancer Handbooks of Cancer Prevention Volume 19 on Oral Cancer Prevention, across five categories of interventions: (1) exposure to preventive dietary agents, (2) quitting exposure to oral cancer risk factors, (3) interventions for smokeless tobacco (SLT) and areca nut cessation, (4) SLT and areca nut control policies, and (5) secondary prevention. The largest number of studies addressed the effect of quitting exposure to a risk factor (n = 57) and control policy interventions (n = 51); 34 studies focused on interventions for SLT and areca nut cessation, 32 evaluated preventive dietary agents, and only 15 assessed secondary prevention. Numerous research gaps were identified, including few youth-targeted studies, a paucity of informative studies evaluating risk reversal upon cessation of use of SLT or areca nut with or without tobacco, negligible evidence on interventions for cessation of use of areca nut with or without tobacco, minimal literature on areca nut control policies, and few studies on screening of high-risk individuals. Overall, the findings highlight the need for further research on multiple areas of SLT and areca nut control in high-burden regions. The findings can inform public health decision-making and support more targeted, evidence-based public health strategies to reduce the burden of oral cancer globally.