Table 2 HPV status and clinico-pathological parameters

Histopathologic subtype

keratinizing

38

15

basaloid

3

2

0.62

Grading

Low-grade (G1-2)

32

11

High-grade (G3-4)

9

6

0.33

Presence of tumour invasion

Non-invasive

5

7

Invasive

36

10

0.028

Presence of metastasis

N0M0

10

5

N+ and/or M+

11

2

0.40

p16 ^INK4a immunostaining

negative

24

0

scattered

10

0

intense nuclear/confluent

7

17

<0.001