Mooren et al, studied presence of p16INK4a expression in tonsillar dysplasia and found that p16INK4a positivity correlated to HPV status.25 Additionally, another study by Masterson et al confirmed increased SYPC2 expression in premalignant carcinoma in situ and invasive carcinoma vs. normal epithelium by LCM and qPCR. This evidence concerns the gene CDKN2A and invasive carcinoma.