Oral sex caused Michael Douglas’s throat cancer, the actor told the Guardian in an interview. “This particular cancer is caused by HPV, which actually comes from cunnilingus,” Douglas said when asked if he regretted his years of smoking and drinking. “I did worry if stress caused by my son’s incarceration didn’t help trigger it. But yeah, it’s a sexually transmitted disease that causes cancer. And if you have it, cunnilingus is also the best cure for it,” Douglas said. Douglas was misdiagnosed at first despite severe oral discomfort, and a specialist in Montreal eventually did a biopsy and diagnosed the Stage 4 cancer in August 2010. He underwent a powerful chemo and radiation treatment for eight weeks, which caused him to lose 45 pounds on a liquid-only diet.