Early oral cancer diagnosis: The Aarhus statement perspective. A systematic review and meta-analysis.

BACKGROUND Mortality is linked to diagnostic intervals in certain cancers. As symptom perception is conditioned by tumor site, a specific study on oral cancer is needed. METHODS This study's inclusion criteria were original data, symptomatic primary oral squamous cell carcinoma, and exposure of interest, diagnostic interval, or diagnostic delay. The outcome of interest was survival and disease stage. A meta-analysis was undertaken to investigate the relationship between intervals to diagnosis, TNM classification, and survival in oral cancer. RESULTS Regarding referral delay, the results present no heterogeneity and showed a risk increase in mortality of 2.48 (range = 1.39-4.42). The larger the diagnostic delay, the more advanced the stage at diagnosis. High quality studies reveal a higher risk increase than low quality studies (odds ratio [OR] = 2.44; 95% confidence interval [CI] = 1.36-4.36 vs OR = 1.53; 95% CI = 1.26-1.86). CONCLUSION A longer time interval from first symptom to referral for diagnosis is a risk factor for advanced stage and mortality of oral cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: E2182-E2189, 2016.