High-risk human papillomavirus infection and p16INK4a protein expression in laryngeal lesions

A total of 88 samples of laryngeal lesions (23 vocal cord nodules (VCNs), 23 papillomas (PAs), 18 dysplasias (DYs), and 24 carcinomas (CAs)) were analyzed for p16INK4a protein (p16) expression by immunohistochemistry and for high-risk human papillomavirus (HR-HPV) infection using chromogene in situ hybridization (CISH) and polymerase chain reaction (PCR). The series comprised 62 males and 26 females, aged 1-87 years (median 55 years). p16 expression was detected in 2 of 23 (9%) VCNs, 18 of 23 (78%) PAs, 9 of 18 (50%) DYs, and 14 of 24 (58%) CAs. Using CISH, HR-HPV DNA was detected in 3 of 23 (13%) VCNs, in 19 of 23 (83%) PAs, in 12 of 18 (67%) DYs, and in 14 of 24 (58%) CAs. HR-HPV DNA was found in six of nine (67%) PAs by PCR. A statistically significant difference in p16 expression and HR-HPV DNA presence detected by CISH was observed between VCNs and PAs (p<0.000001). The sensitivity and specificity of p16 expression for HR-HPV DNA presence detected by CISH was 0.612 and 0.773, respectively. Our study confirms a potential role of HR-HPV infection not only in the pathogenesis of malignant, but also in benign laryngeal lesions.