No abstract

Purpose Promoter hypermethylation has been recently proposed as a mean for HNSCC detection in salivary rinses. In a prospective study of a high-risk population, we showed that EDNRB promoter methylation in salivary rinses is a useful biomarker for oral cancer and premalignancy. Experimental Design Using that cohort, we evaluated EDNRB methylation status and 8 additional genes. Clinical risk assessment by expert clinicians was performed and compared with biomarker performance in the prediction of premalignant and malignant disease. Methylation status of 9 genes was analyzed in salivary rinses of 191 patients by Quantitative methylation-specific PCR. Results HOXA9, EDNRB and DCC methylation were associated (p= 0.012; p<0.0001; p=0.0005) with premalignant or malignant disease. On multivariable modeling, histological diagnosis was only independently associated with EDNRB (p=0.0003) or DCC (p=0.004) methylation. A subset of patients received clinical risk classification (CRC) by expert clinicians based on lesion examination. CRC, DCC and EDNRB were associated with diagnosis of dysplasia/cancer on univariate (p=0.008; p=0.026; p=0.046) and multivariate analysis (p=0.012; p=0.037; p=0.047). CRC identified dysplasia/cancer with56% of sensitivity and 66% of specificity with a similar AUC (0.61, 95%CI=0.60-0.81) when compared to EDNRB and DCC combined AUC (0.60, 95%CI=0.51-0.69), sensitivity of 46% and specificity of 72%. A combination of EDNRB, DCC and CRC was optimal AUC (0.67, 95%CI=0.58-0.76). Conclusion EDNRB and/or DCC methylation in salivary rinses compares well to examination by an expert clinician in CRC of oral lesions. These salivary biomarkers may be particularly useful in oral premalignancy and malignancy screening in clinical care settings in which expert clinicians are not available