RESEARCH COMMUNICATION High p16 Expression Predicts a Positive Response to Chemoradiotherapy in Stage IVa/b Head and Neck Squamous Cell Carcinoma

The etiology of head and neck squamous cell carcinoma (HNSCC) is multifactorial. Genetic factors, diet, occupational exposure, and life style have been implicated in the development of these cancers (Gillison, 2007). Although tobacco and alcohol consumption are traditionally considered the main risk factors in the majority of all HNSCC, infection with human papillomavirus (HPV) is thought to play a role in a subset of HNSCC (Gillison et al., 2008). HPV was detected more frequently in oropharyngeal cancers when compared with cancers in the oral cavity or other HNSCC subsites (Begum et al., 2005; Kreimer et al., 2005; Machado et al., 2010). Unlike cervical cancer, HPV-16 is the most prevalent HPV type found in HNSCC (Gillison et al., 2000). HPV types 18, 31, 33, and 35 are rare (Kreimer et al., 2005; Licitra et al., 2006; Fakhry et al., 2008; Machado et al., 2010). Patients with HPV-positive HNSCCs are clinically distinct from their HPV-negative counterparts; they are more responsive to radiotherapy with or without chemotherapy despite often presenting with locoregionally advanced disease (Smith et al., 2004; Fakhry et al., 2008; Worden et al., 2008). The risk of death from HNSCC has been shown to be lower in these patients when compared with HPV-negative patients (Gillison et al., 2000). Since 1Department of Pathology, 2Department of Medical Oncology, 3Department of Otolaryngology, 4Department of Radiation Oncology, 5Kaohsiung Chang Gung Head and Neck Oncology Group, Cancer Center, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Kaohsiung, Taiwan *For correspondence: [email protected] Abstract