Table 5.

Case-controls studies on the association of marijuana use and head and neck cancer

Characteristics of cases and controlsPrevalence of marijuana useResults
19
Cases = 407, (OSCC)Cases: 25.6%Ever use0.9 (0.6-1.3)Years since first use
Controls = 615Controls: 24.4%Never1.0
Years of use<1 y1.0 (6-1.8)
Never1.0<15 y0.7 (0.3-1.6)
<1 y0.8 (0.4-1.2)16-20 y0.7 (0.3-1.4)
1 y0.2 (0.1-0.7)21-25 y0.9 (0.5-1.7)
2-5 y1.3 (0.6-2.6)>25 y0.9 (0.4-2.0)
6-15 y0.7 (0.4-1.4)
>15 y1.2 (0.6-2.2)
Times used/wkYears since last use
Never1.0Never1.0
<1 y use1.0 (6-1.8)<1 y1.0 (0.6-1.8)
<1 tms/wk0.8 (0.5-1.4.)Current use1.1 (0.6-2.0)
1-7 tms/wk0.8 (0.4-1.6)<10 y0.7 (0.3-1.7)
>7 tms/wk0.5 (0.2-1.6)11-20 y0.7 (0.4-1.3)
>20 y0.7 (0.3-2.1)
20
Cases: 303 oral cancer, 100 pharyngeal cancer, 90 laryngeal cancerOral: 188 (62%)Oral cancerLaryngeal cancer
Pharynx: 40 (40%)Never1Never1
Larynx: 51 (57%)>0 - <1 jnt-y1.1 (0.74-1.5)>0 - <1 jnt-y0.81 (0.42,-1.6)
Controls: 564 (54%)1 - <10 jnt-y1.1 (0.65-1.7)1 - <10 jnt-y0.42 (0.15-1.2)
Controls = 1,04010 - <30 jnt-y0.92 (0.48-1.7)10 - <30 jnt-y0.91 (0.33-2.5)
30 - <60 jnt-y0.88 (0.38-2.0)30 - <60 jnt-y0.71 (0.19-2.7)
≥60 jnt-y1.1 (0.56-2.1)≥60 jnt-y0.84 (0.28-2.5)
Pharyngeal cancer
Never1
>0 - <1 jnt-y0.67 (0.37-1.2)
1 - <10 jnt-y0.71 (0.30-1.7)
10 - <30 jnt-y0.39 (0.10-1.5)
≥60 jnt-y0.57 (0.20-1.6)
18
Cases = 116, OSCCCases: 15 (13%)Ever use1.0 (0.5-2.2)
Controls = 207Controls: 20 (10%)
17
Cases = 53, OSCCCases: 5 (9%)Ever use0.3 (0.1-1.8)
Controls = 91Controls: 14 (15%)
21
Cases = 75, head and neck cancerCases: 16 (21.3%)Ever use1.0 (0.5-2.3)Joint-years
Controls: 39 (12.2%)None1
Controls = 3191st tertile0.4 (0.1-2.2)
2nd tertile1.2 (0.3-4.2)
3rd tertile1.6 (0.5-2.3)
Jnt-y (continuous)1.04 (0.97-1.11)
22
Cases: 240 HNSCCHPV-16–positive:Smoked marijuana monthly for ≥1 y
    HPV-16–positive: 92Cases: 33%HPV-16(+)HPV-16(−)
    HPV-16–negative: 148Controls: 17%Never1.01.0
Controls = 322HPV-16–negative:Former2.3 (0.98-5.4)1.2 (0.52-2.8)
    HPV-16–positive: 184Cases: 21%Current4.7 (1.3-17)2.0 (0.62-6.5)
    HPV-16–negative: 296Controls: 15%Ptrend0.0070.26
No. of joints usually smoked per month
HPV-16(+)HPV-16(−)
≤11.01.0
2-132.5 (0.89-6.8)0.88 (0.29-2.7)
14-293.2 (1.0-10)1.2 (0.36-4.3)
≥305.4 (1.0-28)1.7 (0.41-6.9)
Ptrend0.0070.57
16
Cases = 173, HNSCCCases: 24 (13.8%)Ever use 2.6 (1.1-6.6)Years of use
Controls = 176Controls: 17 (9.7%)01.00
Times/day1-53.9 (0.99-15.0)
01.00>54.9 (1.07-22.3)
14.0 (0.9-17.2)Ptrend0.0134
>15.4 (0.9-33)
Ptrend0.0214

Abbreviations: OSCC, oral squamous cell carcinoma; tms/wk, times per week; jnt-y, joint-years.