• 3/12/2008
  • Chicago, IL
  • staff
  • medheadlines.com

Patient demographics has led researchers at the Johns Hopkins Kimmel Cancer Center to identify two types of cancer associated with the head and neck and the types of people more likely to get one form of the cancer or the other.

The two cancers – one HPV positive and the other HPV negative – usually involve the back of the tongue and the upper throat. HPV is the human papillomavirus, a sexually transmitted disease often associated with cervical cancer.

Patients who develop HPV-positive cancers are most often young, well educated, married, and earn more than $50,000 per year. They are also more likely to have had multiple sex partners, engage in oral sex, and smoke marijuana.

The patients with HPV-negative cancers are often older, smoke tobacco, use alcohol, and neglect oral hygiene.

The rate of HPV-positive cancers has almost doubled in the US in the last 30 years but this form of cancer seems to respond better to treatment, leading to longer survival rates, than the HPV-negative type.

Some risk factors associated with HPV-positive cancers include a history of smoking marijuana, multiple sex partners, casual sex, lack of barrier protection during oral and vaginal sex, and a history of at least one sexually transmitted disease. The risk of cancer increases with marijuana use. Study participants who smoked pot five years or longer were found to be 11 times more at risk of HPV-positive cancers of the head and neck than people who smoke nothing.

Further research is needed to determine whether something in the marijuana hinders the body’s immune system in its fight against infection or if smoking it leads to risky sexual practices.

Poor oral hygiene and heavy tobacco or alcohol use have been known for some time as risky behaviors for oral cancers. It was only recently the HPV factor identified two distinct forms of head and neck cancers. HPV-negative cancers are five times more likely to occur in heavy smokers and drinkers. Brushing one’s teeth less than once a day ups the cancer risk four times.

Each year, about 35,000 Americans are diagnosed with cancers of the head and neck. The Johns Hopkins research team thinks changing sexual behaviors might contribute to the rise in HPV-positive cancers.

Today’s issue, March 12, of the Journal of the National Cancer Institute carries the full story.