MANILA, Philippines -- People who perform oral sex are at a greater risk of developing oral cancers, even higher than those who smoke and drink alcohol, local doctors and dentists said in a joint scientific conference.

Members of the Philippine Medical Association (PMA) and the Philippine Dental Association (PDA) noted that the practice of oral sex can lead to infections of the oral cavity, which may result to cancer of the tonsils, tongue or throat.

The PMA and PDA held the conference as part of this year's National Cancer Consciousness Week celebration.

"Any lesion in the mouth should be seriously considered. Not all can develop to cancer but malignancy must always be taken as an imminent possibility," Dr. Anne Camus, PDA's Manila dental chapter president, said.

Camus added that a nationwide educational campaign must be undertaken to protect Filipinos against the risk of oral cancers.

"The dentists are usually the first to see lesions in the mouth of our patients. At this early point, if the lesion turns out to be malignant, then chances are it is still curable," she said.

For his part, PMA president Dr. Oscar Tinio said: "The PMA, together with our health partners, would like to take a multi-sectoral approach in our information and prevention drive against these dreaded diseases."

A study by the University of the Philippines Population Institute showed that more than four million young Filipinos are sexually active, with only 20% of them using "protection" such as contraceptives. It added that oral sex is a common practice among teens.

On the other hand, a study published in the New England Journal of Medicine suggested that people who had more than five oral sex partners have a nine-fold increase in risk of cancer of the tonsils, tongue or throat.

Oral sex, a sexual act that involves the stimulation of the genitalia using the mouth, is frowned upon in many cultures yet it is commonly practiced across the globe.