Association of Marijuana Smoking with Oropharyngeal and Oral Tongue Cancers: Pooled Analysis from the INHANCE Consortium

Abstract

Background The incidence of oropharyngeal and oral tongue cancers have increased over the last twenty years which parallels increased use of marijuana among individuals born after 1950. Methods Pooled analysis of individual-level data from nine case-control studies from the U.S. and Latin America in the INHANCE consortium. Self-reported information on marijuana smoking, demographic, and behavioral factors was obtained from 1,921 oropharyngeal cases, 356 oral tongue cases, and 7,639 controls. Results Compared with never marijuana smokers, ever marijuana smokers had an elevated risk of oropharyngeal (adjusted odds ratio [aOR]: 1.24; 95% confidence interval [CI]: 1.06, 1.47) and a reduced risk of oral tongue cancer (aOR: 0.47; 95% CI: 0.29, 0.75). The risk of oropharyngeal cancer remained elevated among never tobacco and alcohol users. The risk of oral tongue cancer decreased with increasing frequency (ptrend=0.005), duration (ptrend=0.002), and joint-years of marijuana use (ptrend=0.004), and was reduced among never users tobacco and alcohol users. Sensitivity analysis adjusting for potential confounding by HPV exposure attenuated the association of marijuana use with oropharyngeal cancer (aOR: 0.99; 95% CI: 0.71, 1.25), but had no effect on the oral tongue cancer association. Conclusions These results suggest that the association of marijuana use with Head and Neck Carcinoma may differ by tumor site. Impact The associations of marijuana use with oropharyngeal and oral tongue cancer are consistent with both possible pro- and anti-carcinogenic effects of cannabinoids. Additional work is needed to rule out various sources of bias, including residual confounding by HPV infection and misclassification of marijuana exposure.

Oral Potentially Malignant Disorders among Dental Patients: a Pilot Study in Jordan

“…Socioeconomic status is influential in oral cancer (Moles et al, 2008). Many other factors are possibly implicated in mouth, lip and oropharyngeal cancers, including immunosuppression (van Leeuwen et al, 2009), familial and genetic factors (Turati et al, 2013), diet (Garavello et al, 2009), marijuana use (Marks et al, 2014), and even exercise (Nicolotti et al, 2011).…”

An Epidemiologic Review of Marijuana and Cancer: An Update

“…The analysis included 9 case-control studies from Baltimore, Seattle (407 cases and 615 controls)(13), Latin America, Boston (434 cases and 547 controls)(20), Los Angeles (493 cases and 1,040 controls)(16), and North Carolina, that recruited subjects from 1985 to 2013 (21). The previous INHANCE report (19) had included 5 of these case-control studies; thus 765 of the 1,921 oropharyngeal cancer cases and 211 of the 356 oral tongue cases had been included in the previous analysis.…”

Oral health assessment for users of marijuana and cocaine/crack substances

“…However, because the duration of illicit drug use was even less than of legal drugs, it is likely that the absence of lesions is due to the short duration of illicit drug use in our sample. Carvalho et al 30 found no association between lifetime marijuana use and the risk for development of oral cancer, while Marks et al 5 suggested that the association of marijuana use with head and neck carcinoma may differ by tumor site. Because of the scarcity of studies and variations between them, it is difficult to define the relationship between amount of marijuana smoked and the appearance of mucosal lesions.…”

“…1,4 Moreover, users are more prone to oral infections, possibly due to alterations in oral immunology, 2 and drug use can be associated with dysplastic changes and potentially malignant disorders of the oral mucosa, increasing the incidence of squamous cell carcinoma. 5 Marijuana cigarettes can contain up to twice the amount of polycyclic aromatic hydrocarbons as tobacco cigarettes, and the usual consumption without a filter leads to a higher concentration of inhaled smoke. However, the relationship between marijuana use and oral cancer is still not clear.…”

“…6 The association between marijuana and oropharyngeal and tongue cancers suggests that the biological effects of C. sativa are pro-and anti-carcinogenic. 5 Marks et al 5 observed that C. sativa play a role in immune cells, suppressing pro-inflammatory cytokine production and enhancing anti-inflammatory cytokine production, leading to reduced host immune responses as well as suppression of anti-tumor immunity. Additionally, it has also been shown in epithelial cell lines that marijuana has antitumor effects through the arrest of uncontrolled cell growth, enhancement of apoptosis, downregulation of angiogenesis, and cellular migration.…”