Koos Boeve

149 Methylation biomarkers for the detection of tumor DNA in saliva neoplastic-enriched areas were macrodissected and used for DNA extraction. From the FF tissues, approximately four 10 µm thick sections were cut. Both, the FF and FFPE sections were incubated overnight at 60°C in 300 µl 1% SDS-proteinase K solution. Table 1. Clinical characteristics of all included subjects Patient characteristics OSCC Patients (n) Non age-matched Controls (n) Age-matched Controls (n) Total 10 5 5 Age (years) * Median (IQR) 63 (58 to 74) 45 (30 to 62) 67 (57 to 70) Gender ** Male 7 2 4 Female 3 3 1 Saliva DNA yield (µg)*** Median (range) 64 (6 to 140) 32 (16 to 75) 32 (20 to 57) FFPE tumor tissue 9 NA NA FF tumor tissue 6 NA NA Tumor localization NA NA Tongue 4 NA NA Gum 2 NA NA Floor-of-mouth 3 NA NA Cheek 1 NA NA pT NA NA 1-2 7 NA NA 3-4 3 NA NA pN NA NA 0 5 NA NA + 2 NA NA X 3 NA NA Infiltration depth (mm) NA NA Median (range) 3 (1 to 23) NA NA Tumor diameter (mm) NA NA Median (range) 22 (7 to 52) NA NA * OSCC versus orthognatic, p = 0.050; no significant differences between the other groups . ** No significant differences between patient and control groups. *** No significant differences between patient and control groups. Abbreviations: OSCC, oral squamous cell carcinoma; IQR, interquartile range; ug, microgram; mm, millimeter; NA, not applicable; FFPE, formalin fixed, paraffin embedded; FF, fresh frozen.