Study: Cannabis Use Not Associated with Elevated Risk of Secondary Cancer Diagnosis

Hamilton, Canada: Patients with head and neck cancers who possess a history of cannabis use are not at an increased risk of developing a secondary cancer diagnosis, according to data published in the journal Cureus.

A team of researchers affiliated with McMaster University, the University of Toronto, and the University of British Columbia assessed the association between cannabis smoking and the risk of developing a second primary squamous cell carcinoma in patients previously diagnosed with head and neck cancer.

Investigators reported that those who consumed cannabis “showed lower odds of developing SPC” compared to non-users.

“These results suggest that cannabis behaves differently than tobacco smoking,” they concluded. “Our results are consistent with the theory that cannabis is not carcinogenic and hence would not follow patterns of field cancerization.”

The study’s findings are consistent with those of prior papers concluding that cannabis smoke and tobacco smoke are not equally carcinogenic and that marijuana smoke exposure is not associated with many types of tobacco-related diseases, such as lung cancer and COPD.

Full text of the study, “Rate of second primary head and neck cancer with cannabis use,” appears in Cureus. Additional information is available from the NORML white paper, “All Smoke Is Not Created Equal.”