Saturday, March 27, 2010

Oral Sex: Cancer Risk or Drug Company Marketing Ploy?

In a report appearing in yesterday’s British Medical Journal, researchers suggested there MIGHT be a connection between certain types of head and neck cancer and oral sex that involves the transmission of semen.

Despite an overall slight decline in head and neck cancers in recent years, cases of a particular form called oropharyngeal squamous cell carcinoma (OSCC) have increased sharply, particularly in the developed world. This growth seems to be linked to cancers caused by the human papillomavirus (HPV), scientists said in the report.

But, is this report about public health, or is it more about money and drug sales?

Two vaccines – Cervarix, made by GlaxoSmithKline, and Gardasil, made by Merck & Co. – can prevent HPV. HPV causes virtually all cases of cervical cancer, the second most common cancer in women worldwide. Many first-world nations have launched HPV immunization programs for girls as young as 12 to try to protect them from the common sexually transmitted virus before they become sexually active.

The scientists, led by Hisham Mehanna, M.D., said while including boys in immunization plans has been seen as too expensive, it may be time to look again.

"We need to look at the evidence again to re-evaluate the cost-effectiveness of male children in light of this new and rapidly rising incidence," he said in an interview.

U.K. economic analyst Savvas Neophytou at Panmure Gordon in London said such studies would dispel worries about sales prospects for HPV vaccines, and repeated his 'buy' recommendation for Glaxo stock.

"The emergence of new data such as this may increase motivation amongst national vaccination authorities worldwide to re-double efforts to vaccinate children before they become sexually active," Neophytou said in an equity research note.

As you might imagine, the study and the blatant link to pharmaceutical companies has triggered a lot of online and blogger debate regarding the veracity of the conclusion, and whether it might instead be a not-so-veiled attempt by the drug companies to boost sagging sales of their vaccines.

Most troubling is that lead author Mehanna is also director of the GlaxoSmithKline-funded Institute of Head and Neck Studies and Education at University Hospital in Coventry, U.K.

In a footnote to yesterday’s article, it’s disclosed that Mehanna, “is the director of an institute that does contract work for GlaxoSmithKline that has interests in head and neck cancers.” In the media, the footnote information has gotten less substantially attention than a possible “oral sex virus.”

And, a second study author has also reported either being involved with contract work or receiving research grants from pharmaceutical companies.

So how seriously should this oral sex cancer scare be taken? According to the study, it is uncommon in the U.S., affecting fewer than two people per 100,000:

“…the incidence of oropharyngeal squamous cell carcinoma increased by 22 percent from 1.53 per 100,000 to 1.87 per 100,000 between 1999 and 2006.”

In the U.K., it’s somewhat more serious; it’s up to 11 per 100,000:

“The United Kingdom has seen a 51 percent increase in oral and oropharyngeal squamous cell carcinoma in men from seven per 100,000 to 11 per 100,000 between 1989 and 2006.”

Mehanna and his colleagues said the increased incidence of HPV-related oropharyngeal squamous cell carcinoma may result from sexual transmission through orogenital intercourse (oral sex.)

Cervarix isn’t approved for males, or for preventing head and neck cancers. The competing product, Merck’s Gardasil, is approved for preventing genital warts in boys (the precursor to cancer). Both companies would like the FDA and European authorities to expand the number of reasons people should be given their vaccines.
This link to oral sex was made, the researchers reported, because this type of mouth cancer occurs when the tumor is in the back of the mouth, where it joins the throat. As a result, the authors suggested sexual transmission of HPV through oral sex as a possible reason for the increase in those cases linked to the virus.

Researchers suggest that this increasing form of mouth cancer is likely due to sexual transmission of HPV, pointing to data from a recent analysis of more than 11,0000 people showing that individuals with six or more sexual partners had a 25 percent higher risk for developing the disease.

Additionally, the risk for this type of mouth cancer was nearly three times higher in individuals with four or more oral sex partners. As the authors sum up: "Sexual transmission of HPV – primarily through orogenital intercourse might be the reason for the increase in incidence of HPV related oropharyngeal carcinoma."

Mehanna said HPV-related mouth cancer seemed to be a relatively new disease that was different from non-HPV related cancers in the mouth. Mouth and throat cancers are normally associated with excessive smoking and drinking and they usually strike older people, killing around a third of sufferers within two years.

However HPV-related cases have fairly good survival rate with around eight in 10 still alive two years after diagnosis or higher depending on how advanced the cancer was when found.

In the accompanying commentary that also appeared in the British Medical Journal said: "There are also public health implications. Female only HPV vaccination programmes may affect the incidence of HPV related oropharyngeal carcinoma. A recent modelling study of the effects of HPV vaccination in males concluded that routinely vaccinating boys for HPV could not be justified on health economic grounds.

"The recent rapid rise in HPV related oropharyngeal carcinoma may alter the cost effectiveness of vaccinating boys before they become sexually active."

Nell Barrie, Cancer Research UK’s science information officer, said: “We know that HPV can cause oropharyngeal cancer, as well as several other types of cancer including cervical cancer. But although HPV infection is common, the virus causes cancer only in a minority of people. More research will be needed to determine if patients with HPV related head and neck cancer could benefit from different treatment, and to understand if any changes to health services are needed.

“It will also be interesting to see if the HPV vaccine could help to reduce rates of oropharyngeal cancer. The vaccine protects against cervical cancer by immunizing women against the two most common cancer-causing types of HPV.”

Even though the HPV-related form of mouth cancer tends to impact younger people and often has a better prognosis than other forms of the disease, researchers question whether public health initiatives currently cast a wide enough net to prevent its spread.

A study published last fall in the British Medical Journal suggested that HPV vaccination for boys wasn't cost-effective, or, as the researchers from the Harvard School of Public Health phrased it: "... including boys in an HPV vaccination programme [sic] generally exceeds conventional thresholds of good value for money."

Mehanna and colleagues question those findings, writing that "the low incidence of HPV related oropharyngeal carcinoma in that study has led to concern because the recent rapid rise in HPV related oropharyngeal carcinoma may alter the cost effectiveness of vaccinating boys before they become sexually active."

There will be public health implications to this increased incidence, the authors write. For example, vaccinating boys for HPV has not been viewed as cost-effective in the past, but may in the future. Also, HPV status may become an important diagnostic and prognostic factor in oropharyngeal carcinoma, and a stratification category in research studies. In addition, HPV-related disease generally has better survival rates than non-HPV-related disease.

"To date, we have no good evidence to support managing patients with HPV-related head and neck cancer differently from those whose tumors are not HPV related, although several studies are being planned to evaluate different treatment options," the authors write.

The next step in research is to determine how treatment of HPV-related oropharyngeal carcinoma may differ from treatments for other types of head and neck cancer, the authors conclude, suggesting that patients with HPV-related forms of the disease should be encouraged to enroll in clinical trials designed to improve treatment, and tailor it to this specific form of the disease.

It’s true that the signs and symptoms of oral cancer often go unnoticed. However, there are a few visible signs associated with these cancers that require immediate attention, including:

• Red or white patches in the mouth that last more than two weeks
• Change in voice or hoarseness that lasts more than two weeks
• Sore throat that does not subside
• Pain or swelling in the mouth or neck that does not subside
• Lump in the neck
• Ear pain
• Difficulty speaking or swallowing
• Difficulty breathing

Anyone who is concerned, should consult a physician.

— The Curator


  1. When scientific research receives the majority of its funding from business sources, there will always be doubt about the validity of the results. A society that does not maintain a strong research capability will have no means of independently assessing the business-funded research. Are we willing to let our health be bought simply because we are unwilling to maintain a strong, and stable, publicly-funded science program?

    Is Still Here

  2. Here, here! Could not have said it better! Thanks for this wonderful comment.