| HPV positive tumours | HPV negative tumours |
Anatomical site | Tonsil & base of tongue | All sites |
Histology | Non-keratinised | Keratinised |
Age | Younger Cohorts | Older cohorts |
Sex ratio | 3:1 men | 3:1 men |
Stage | Tx, T1-2 | Variable |
Risk factors | Sexual behaviour | Alcohol & tabacco |
Incidence | Increasing | Decreasing |
Survival | Improved | Unchanging |