Michael Douglas says his throat cancer may have stemmed from HPV. (Image credit: David Azia/AP Photo)

Two-and-a-half years after beating throat cancer, Michael Douglas is linking the disease to a virus sometimes contracted through oral sex.

In an interview with The Guardian newspaper, Douglas, 68, said the walnut-sized tumor at the back of his throat may have stemmed from the human papillomavirus, a sexually-transmitted infection best known for its role in causing cervical cancer in women.

The statement made headlines in newspapers and on morning shows, including "Good Morning America." But a rep for the actor has since clarified that Douglas didn't blame his specific cancer on oral sex - he simply meant that oral sex was a suspected cause of certain oral cancers.

HPV-Related Cancers on Rise as Vaccination Rates Stay Low

Each year about 6,700 American men are diagnosed with oropharyngeal cancer tied to HPV, according to the U.S. Centers for Disease Control and Prevention. The virus can also cause cancers of the cervix, vagina, vulva, anus and throat in women, as well as penile and anal cancer in men.

All told, the virus is implicated in more than 28,000 cancer cases each year, according to the CDC:

• 12,000 cervical cancers
• 2,100 vulvar cancers
• 500 vaginal cancers
• 600 penile cancers
• 2,800 anal cancers in women
• 1,500 anal cancers in men
• 1,700 oropharyngeal cancers in women
• 6,700 oropharyngeal cancers in men

Tobacco and alcohol use can also contribute to the risk of throat cancer, according to the agency, but about 21,000 of the 28,00 cancer cases could be prevented by a vaccine that blocks HPV infections.

" We've been vaccinating young girls against HPV for many, many years, and now we vaccinate young boys against it," said ABC News' chief health and medical editor Dr. Richard Besser, explaining how the CDC recommends the vaccine Gardasil for all boys and girls aged 11 and 12. "The key thing is you need to vaccinate people before they pick this up."

HPV Vaccine for Boys Urged By CDC

Besser said some parents struggle with the idea of vaccinating young kids against a sexually-transmitted disease.

"Parents don't like to think about their children eventually becoming sexually active," he said. "But taking this prevention step when kids are young can prevent a cancer, and that's amazing."