Actor Michael Douglas revealed to the British newspaper The Guardian that his throat cancer was caused by the human papillomavirus.
Douglas, 68, contracted the virus which turned into cancer by performing oral sex.
The Hollywood legend who is married to starlet Catherine Zeta-Jones added that the stress caused by his son's incarceration may have triggered the cancer.
The strain of HPV Douglas developed is a known link to oral cancer.
"Human papillomavirus is a huge risk factor. The numbers are going up with all this awareness of the dangers of smoking," said Dr. David Samadi, who has not treated Douglas.
When he was finally diagnosed after months of pain, Douglas had stage four cancer.
"He complained about ear pain. He had problems with his teeth. He was given antibiotics which was a big mistake. He goes on for a few months until someone examined him and found a wall of big cancer at the base of his throat. They found a tumor at the base of his throat," said Dr. Samadi.