Daily marijuana use linked to increased risk of deadly head and neck cancers, study finds

 Using marijuana daily for years may raise the overall risk of head and neck cancers by 3.5% to 5%, according to a new study that analyzed millions of medical records.

“Our research shows that people who use cannabis, particularly those with a cannabis use disorder, are significantly more likely to develop head and neck cancers compared to those who do not use cannabis,” said senior study author Dr. Niels Kokot, a professor of clinical otolaryngology-head and neck surgery at the Keck School of Medicine at the University of Southern California in Los Angeles.

Cannabis use disorder is diagnosed when a person has two or more of such symptoms as craving weed, becoming tolerant to its effects, using more than intended, using marijuana even though it causes problems in life, using it in high-risk situations, experiencing withdrawal and being unable to quit, according to the US Centers for Disease Control and Prevention.

“While our study did not differentiate between methods of cannabis consumption, cannabis is most commonly consumed by smoking,” Kokot said in an email. “The association we found likely pertains mainly to smoked cannabis.”

Some 69% of people with a diagnosis of oral or throat cancer will survive five years or longer after their diagnosis, according to the National Cancer Institute. If the cancer metabolizes, however, that rate drops to 14%. About 61% of people diagnosed with cancer of the larynx will be alive five years later — a rate that drops to 16% if the cancer spreads. [Read More @ CNN]