'Oral sex caused my cancer': Michael Douglas reveals sexually transmitted disease was behind his throat tumour Actor had believed it was years of smoking and drinking that caused disease Claims cancer strain stems from human papilloma virus spread via oral sex Douglas now in the clear after 2010 diagnosis By Emily Sheridan Hollywood actor Michael Douglas has claimed that his throat cancer was caused by performing oral sex on women. The star, who fought a six month battle with the disease from August 2010 until January 2011, had initially believed that it was his years of smoking and drinking that had lead to the illness. However, in a new interview the 68-year-old said that the particular strain he had suffered with was caused by human papilloma virus (HPV), a sexually transmitted disease. Opening up: Michael Douglas, pictured on the Graham Norton Show last week, has spoken about the causes of his throat cancer Douglas made the frank admission about how he developed the illness during an interview with The Guardian newspaper when he was asked if he had regretted smoking and drinking in the past. Douglas candidly replied: 'No. Because without wanting to get too specific, this particular cancer is caused by HPV, which actually comes about from cunnilingus. Douglas, who is married to Welsh actress Catherine Zeta-Jones, was diagnosed with cancer in August 2010 after a walnut-sized tumour was found on his tongue. His health troubles started just a few months after his eldest son Cameron - from his first marriage to Diandra Luker - was jailed for drug possession and dealing. The actor admitted he initially believed his disease had been triggered by the stress over his son's legal troubles. Fighting back: Michael in November 2010, when he was battling cancer He explained: 'I did worry if the 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 was diagnosed with stage four of the disease and underwent an intense course of chemotherapy and radiation. Eventually, he was given the all-clear, although he still has to undergo check-ups with doctors every six months. However, the actor is optimistic he has conquered the disease once and for all. 'With this kind of cancer, 95 per cent of the time it doesn't come back,' he said. Family man: Michael with his wife Catherine Zeta-Jones and their two children Dylan and Carys More than 20 years ago, Michael was hospitalised for an addiction, which many reports at the time claimed was to sex. However, he has since denied that he was a sex addict, insisting that he was being treated for alcohol abuse. HPV is a sexually transmitted virus which is more widely known as a cause of cervical and anal cancer. Last year, Cancer Research UK said the rising rates of HPV16-positive cases of oral cancer could be linked to oral sex. Human papilloma virus (HPV) is spread through sexual contact and is more usually associated with cervical cancer in women. The cervical cancer jab given to 12 and 13-year-old schoolgirls aims to cut their odds of the cancer by protecting them against the virus. Although most mouth and throat cancers are normally blamed on drinking and smoking an increasing number of cases that occur around the tonsils and back of the tongue are due to HPV. Although the cancer is not contagious, the virus is. In the US, HPV is blamed for up to 80 per cent of these tumours of the tonsils and the back of the tongue, which experts say could be due to increasing popularity of oral sex. The typical patient is described as an otherwise healthy man in his late 40s or early 50s who has never smoked or smoked very little. In Britain, the number of mouth and throat cancers have increased by 40 per cent in just a decade, to 6,200 cases a year. Cancer Research UK says the HPV virus may be key to the "rapid rise." Symptoms include persistent mouth ulcers, pain, discoloured patches and difficulty chewing and swallowing. Men are advised to check their neck for lumps when shaving and both sexes to look at the back of their throat while brushing their teeth. Treatments such as chemotherapy, radiotherapy and surgery are often more successful in mouth and throat cancers caused by the virus than those caused by tobacco and alcohol. Although mouth cancer can be caused by HPV passed on by oral sex, doctors say Michael Douglas's claim that oral sex is also a cure doesn't make any medical sense.