Study register · detailPopulationsbasierte Fall-Kontroll-Studie · Cancer Risk · 2009
A population-based case-control study of Cannabis use and head and neck squamous cell carcinoma.
Liang et al.·Cancer Prevention Research
Clear benefitGRADEHigh65 citations
Samplen = 981 Pat.
DurationDecember 1999 to December 2003
ControlNever-users
EndpointHNSCC risk
Blindingn.a.
DesignPopulationsbasierte Fall-Kontroll-Studie
Cannabinoidvollspektrum
Routeinhalativ
”Key finding
Moderate cannabis use was associated with a markedly reduced risk of head and neck squamous cell carcinoma.
Summary
Population-based case-control study (n=434 HNSCC cases, n=547 controls, Boston MA); 10–20 years of cannabis use vs. never-users: significantly reduced HNSCC risk (OR=0,38, 95% CI 0,22–0,67); moderate weekly use also associated with reduced risk (OR=0,52, 95% CI 0,32–0,85); trend p<0,001; inverse association independent of HPV-16 antibody status.
P
PopulationAdults with head and neck squamous cell carcinoma (HNSCC) as well as controls from the general population, greater Boston, MA area; cases n=434, controls n=547
I
InterventionLifetime cannabis exposure (assessed by duration, frequency, and age at onset)
C
ControlNever-users (controls, frequency-matched by age, sex, place of residence)
O
Outcome10–<20 years of cannabis use significantly associated with reduced HNSCC risk (OR 0,38; 95%-KI 0,22–0,67); moderate weekly use also protective (OR 0,52; 95%-KI 0,32–0,85); trend for later age at onset (p<0,001)
Confidence in the evidence
Very lowLowModerateHigh
High
The highest of four GRADE levels, the effect estimate is very reliable.
Quality profile
Sample size★★★★★
Blinding—
Effect sizeClear benefit
Citations / year★★★★★
Authors
Liang C, McClean MD, Marsit C, Christensen B, Peters E, Nelson HH, Kelsey KT.
Cannabinoids, constituents of Cannabis smoke, have been recognized to have potential antitumor properties. However, the epidemiologic evidence addressing the relationship between Cannabis use and the induction of head and neck squamous cell carcinoma (HNSCC) is inconsistent and conflicting. Cases (n = 434) were patients with incident HNSCC disease from nine medical facilities in the Greater Boston, MA area between December 1999 and December 2003. Controls (n = 547) were frequency matched to cases on age (+/-3 years), gender, and town of residence, randomly selected from Massachusetts town books. A questionnaire was adopted to collect information on lifetime Cannabis use (decade-specific exposures) and associations evaluated using unconditional logistic regression. After adjusting for potential confounders (including smoking and alcohol drinking), 10 to 20 years of Cannabis use was associated with a significantly reduced risk of HNSCC [odds ratio (OR)(10-<20 years versus never users), 0.38; 95% confidence interval (CI), 0.22-0.67]. Among Cannabis users moderate weekly use was associated with reduced risk (OR(0.5-<1.5 times versus <0.5 time), 0.52; 95% CI, 0.32-0.85). The magnitude of reduced risk was more pronounced for those who started use at an older age (OR(15-<20 years versus never users), 0.53; 95% CI, 0.30-0.95; OR(> or =20 years versus never users), 0.39; 95% CI, 0.17-0.90; P(trend) < 0.001). These inverse associations did not depend on human papillomavirus 16 antibody status. However, for the subjects who have the same level of smoking or alcohol drinking, we observed attenuated risk of HNSCC among those who use Cannabis compared with those who do not. Our study suggests that moderate Cannabis use is associated with reduced risk of HNSCC.