Abstract. Human papillomavirus (HPV)-positive tonsillarand base of tongue cancer is increasing epidemically and has much better outcome than corresponding HPV-negativeIn 2007, human papillomavirus (HPV) was recognized as a risk factor for oropharyngeal squamous cell carcinoma (OPSCC) by the International Agency for Research against Cancer (IARC), besides the traditional risk factors smoking and alcohol (1-4). Concurrently, an increased incidence of OPSCC, more specifically tonsillar and base of tongue cancer (TSCC and BOTSCC, the two main HPV-positive OPSCC sites) was described in many developed countries, and found to be due to a sharp rise of HPV-positive cases (5-18). These HPV-positive tumors had a much better clinical outcome than their HPV-negative counterparts and head and neck squamous cell carcinoma (HNSCC) in general when treated with radiotherapy and surgery (1-3, 15-17, 19, 20). Treatment of HNSCC including OPSCC has, however, gradually become more intensified with induction chemotherapy or concurrent chemo-radiotherapy and sometimes the administration of Erbitux, leading to more severe side effects (16, 20, 21). This is likely unnecessary for most HPV-positive TSCC and BOTSCC patients since they generally respond well to less therapy and furthermore, intensified therapy does not improve survival of [15][16][17] 20, 22, 23). It is, therefore, important to identify patients with HPV-positive TSCC and BOTSCC eligible for less treatment or targeted therapy and efforts focus now on finding predictive and targetable markers for these patients (24-39).Here, a short background of the field and an update on recent attempts to find predictive and targetable markers with different methodologies for individualized therapy is presented.
Human Papillomavirus in Tonsillar and Base of Tongue Squamous Cell Carcinoma and an Epidemic Increase of these TumorsIn 2000, an association between HPV and OPSCC and TSCC was reported, and with radiotherapy and surgery, these HPVpositive cases had much better outcome than corresponding HPV-negative cases (80% vs. 40-50% 5-year survival) (1, 2). In 2004, a similar relationship of HPV to BOTSCC, but not to mobile tongue cancer was disclosed (40). Based on 5319