Table 3.
Multivariable factors associated with HPV16-positive oropharyngeal cancer
| Overall (N = 533) |
US (N = 243) |
Europe (N = 119) |
Brazil (N = 171) |
||||
|---|---|---|---|---|---|---|---|
| Risk factor | N | % HPV16 positive2 | OR (95% CI)3 | OR (95% CI)3 | OR (95% CI)3 | OR (95% CI)3 | p-heterogeneity1 |
|
| |||||||
|
Age (10 year increase) |
533 | – | 0.95 (0.71–1.27) | 0.75 (0.49–1.16) | 0.98 (0.53–1.81) | 1.21 (0.39–3.78) | 0.64 |
| Sex | |||||||
| Men | 447 | 33.8 | 1.0 | 1.0 | 1.0 | 1.0 | |
| Women | 86 | 43.0 | 0.56 (0.27–1.15) | 0.65 (0.22–1.96) | 0.34 (0.07–1.68) | 0.42 (0.02–8.19) | 0.79 |
| Education level | |||||||
| ≤Primary school | 252 | 15.9 | 1.0 | 1.0 | 1.0 | 1.0 | |
| Secondary school | 144 | 40.3 | 2.31 (1.23–4.35) | 2.68 (0.88–8.13) | 1.76 (0.54–5.72) | 17.59 (0.56–555.11) | 0.45 |
| Any college | 131 | 67.9 | 3.60 (1.77–7.30) | 2.23 (0.82–6.06) | 0.29 (0.01–7.69) | 25.24 (0.45–1,410.25) | 0.24 |
| Race | |||||||
| Caucasian | – | – | – | 1.0 | – | – | |
| Black | – | – | – | 0.04 (0.01–0.13) | – | – | |
| Mixed | – | – | – | 0.15 (0.01–3.16) | – | – | |
| Lifetime sex partners | |||||||
| 0–3 | – | – | – | 1.0 | – | – | |
| 4–5 | – | – | – | 4.21 (1.36–13.0) | – | – | |
| Stage4 | |||||||
| I | 25 | 32.0 | 1.0 | 1.0 | 1.0 | 1.0 | |
| II | 44 | 27.3 | 0.79 (0.20–3.11) | 0.91 (0.16–5.25) | – | – | |
| III | 35 | 39.8 | 1.62 (0.49–5.32) | 1.93 (0.38–9.77) | 1.21 (0.11–13.78) | – | 0.75 |
| IV | 120 | 35.7 | 2.49 (0.83–7.45) | 1.73 (0.41–7.37) | 3.20 (0.35–28.89) | – | 0.65 |
| Smoking status | |||||||
| Never | 57 | 82.5 | 1.0 | 1.0 | 1.0 | 1.0 | |
| Pack years5 | 472 | 29.8 | 0.75 (0.64–0.87) | 0.84 (0.66–1.06) | 0.59 (0.41–0.84) | 0.36 (0.13–0.99) | 0.10 |
| Alcohol status | |||||||
| Never | 39 | 53.8 | 1.0 | 1.0 | 1.0 | 1.0 | |
| Drink years5 | 478 | 33.9 | 0.64 (0.54–0.76) | 0.64 (0.48–0.84) | 0.62 (0.44–0.87) | 0.40 (0.15–1.05) | 0.66 |
| Region | |||||||
| US | 243 | 59.3 | 1.0 | – | – | – | |
| Europe | 119 | 31.1 | 0.42 (0.22–0.82) | – | – | – | |
| Brazil | 171 | 4.1 | 0.04 (0.01–0.09) | – | – | – | |
1
chi-squared test for heterogeneity across the studies.
2
HPV16 positivity was define as tumor positive for HPV16 DNA and overexpressing P16INK4a protein.
3
Estimates were adjusted for age, sex, education level, stage, region, smoking (10 pack year intervals) and alcohol consumption (10 drink year intervals) as appropriate.
4
Seven HPV16 positives in Brazil were all of advanced stage.
5
Denotes increments of 10 pack years or drink years until 40 or more as appropriate.