Researchers At UCLA’s Jonsson Cancer Center Report Smoking Marijuana May Increase Risk Of Head And Neck Cancers
11/28/2007 Los Angeles, CA staff ScienceDaily (www.sciencedaily.com) Researchers at UCLA's Jonsson Cancer Center are reporting, for the first time, that smoking marijuana may increase the risk of head and neck cancers. Previous laboratory and clinical studies have indicated that marijuana use may be related to molecular alterations in the respiratory tract, changes that may lead to cancer. This is the first study to examine whether smoking marijuana increases risk of head and neck cancers, said Dr. Zuo-Feng Zhang of UCLA's Jonsson Cancer Center, a professor in the Department of Epidemiology in the UCLA School of Public Health and director of the cancer epidemiology training program at UCLA. "Most people don't think about marijuana in relationship to cancer," said Zhang, lead author of the journal article. "The carcinogens in marijuana are much stronger than those in tobacco. The big message here is that marijuana, like tobacco, can cause cancer." Zhang studied the relationship between marijuana use and head and neck cancers in 173 patients diagnosed with those diseases. He compared those findings to 176 cancer-free control patients, and found that those who habitually smoked marijuana were at higher risk for head and neck cancers. The epidemiological data was collected using a structured questionnaire, which queried patients about their histories of tobacco smoking, marijuana smoking and alcohol use. Zhang said researchers were able to evaluate the data on marijuana smoking independently from data on tobacco smoking and alcohol use, which also increase the risk of certain cancers. The results of the study [...]