Hollywood superstar Michael Douglas has revealed that he believes his throat cancer was caused by performing oral s**.

The actor, who is now 68 years old and married to Catherine Zeta Jones, spoke out in a recent interview with The Guardian newspaper, explaining that the cancer he was diagnosed with three years ago was actually caused by the human papillomavirus (HPV), which is thought to be contracted through cunnilingus.

Douglas explained during the interview that he was not regretful about smoking and drinking in his past, as these factors were not responsible for his cancer.

He said: “Yeah, it’s a s**ually transmitted disease that causes cancer.

And if you have it, cunnilingus is also the best cure for it.” However, he did admit that he had considered whether the stress caused by his son’s incarceration may have contributed to the development of the cancer.

When Douglas was first diagnosed with the cancer in August 2010, he had been experiencing many months of oral discomfort.

However, a number of specialists missed the tumour and instead prescribed antibiotics.

It was only when he visited a friend’s doctor in Montreal that the tumour was detected using a tongue depressor.

Shortly afterwards, he was diagnosed with stage four cancer, which can often be terminal, and underwent an intensive eight-week course of chemotherapy and radiation.

Despite the fact that the treatment left him extremely weak after the loss of 20kg on a liquids-only diet, he refused to use a feeding tube.

Douglas’ cancer was initially thought to be related to his smoking and drinking habits, as well as his addiction to s**, which led to his hospitalisation in 1992.

However, HPV is now believed to be responsible for an increasing proportion of oral cancers, with some suggesting that changes in s**ual behaviour, specifically an increase in oral s**, could be playing a role.

This could be due to cultural changes or fears about the safety of penetrative s** following the AIDS epidemic.

Consultant head and neck surgeon Mahesh Kumar has confirmed that the last decade has seen a dramatic rise in this form of cancer, particularly among younger sufferers.

Recent studies have found that 57% of 1,316 patients with oral cancer were HPV-16 positive.

Kumar stated that it has been established beyond reasonable doubt that HPV type 16 is the causative agent in oropharyngeal cancer, which would help explain why Douglas was given an 80% chance of survival despite the advanced stage of his illness.

Although it is calculated that between 25% and 35% of oral cancers are HPV-related, it cannot be explicitly said to cause any particular cancers.

HPV is common, with around 90% of s**ually active people having been exposed to some form of genital HPV by the age of 25.

There are more than 100 variants of HPV, which appear in different parts of the body and manifest themselves in different ways, with some causing warts and others being symptomless.

HPV-related oral cancers are most common in heterosexual men in their 40s and 50s.

Teenage girls in the UK and other countries are now vaccinated against HPV, which should protect them from cervical cancers and – it is believed – future partners from HPV-related oral cancers.

Douglas has two children with Zeta Jones, aged 10 and 12, as well as an older son from a previous marriage who is currently serving a lengthy prison sentence for drugs possession and dealing.

Despite concerns that confirmation of the association between HPV and oral cancer could lead to inappropriate questioning of patients, GPs have shown interest in how it will affect the rollout of the HPV vaccine, which is currently restricted in the UK.