Source: Journal of Clinical Oncology, Vol 27, No 12 (April 20), 2009: pp. 1992-1998
Authors: Pernille Lassen et al.

Purpose:
A subset of head and neck cancers is associated with the human papillomavirus (HPV). Viral infection is closely correlated with expression of p16INK4A in these tumors. We evaluated p16INK4A as a prognostic marker of treatment response and survival in a well-defined and prospectively collected cohort of patients treated solely with conventional radiotherapy in the Danish Head and Neck Cancer Group (DAHANCA) 5 trial.

Patients and Methods:
Immunohistochemical expression of p16INK4A was analyzed in pretreatment paraffin-embedded tumor blocks from 156 patients treated with conventional primary radiotherapy alone. The influence of p16INK4A status on locoregional tumor control, disease-specific survival, and overall survival after radiotherapy was evaluated.

Results:
p16INK4A positivity was found in 35 tumors (22%). Tumor-positivity for p16INK4A was significantly correlated with improved locoregional tumor control (5-year actuarial values 58% v 28%; P = .0005), improved disease-specific survival (72% v 34%; P = .0006), and improved overall survival (62% v 26%; P = .0003). In multivariate analysis, p16INK4A remained a strong independent prognostic factor for locoregional failure (hazard ratio [HR], 0.35; 95% CI, 0.19 to 0.64), disease-specific death (HR, 0.36; 95% CI, 0.20 to 0.64), and overall death (HR, 0.44; 95% CI, 0.28 to 0.68).

Conclusion:
Expression of p16INK4A has a major impact on treatment response and survival in patients with head and neck cancer treated with conventional radiotherapy.

Authors:
Pernille Lassen, Jesper G. Eriksen, Stephen Hamilton-Dutoit, Trine Tramm, Jan Alsner, Jens Overgaard

Authors’ affiliation:
From the Department of Experimental Clinical Oncology and Institute of Pathology, Aarhus University Hospital, Denmark.

Notes:
1. Written on behalf of the Danish Head and Neck Cancer Group.
2. Supported by grants from the Danish Cancer Society, The Danish Council for Strategic Research, and the Lundbeck Foundation Research Centre for Interventional Research in Radiation Oncology.
3. Presented in part at the International Meeting on Innovative Approaches in Head and Neck Oncology, February 22-24, 2007, Barcelona, Spain.