The results of the study, which mainly cover the Swedish capital of Stockholm, show that this increase is directly linked to the human papillomavirus (HPV).
"The number of cases of tonsillar carcinoma is rising throughout Sweden, but the link to HPV has so far only been studied in Stockholm," says Professor Tina Dalianis, one of the researchers behind the study. "However, Stockholm is a typical European city so we suspect that the results indicate a general trend."
Tonsillar carcinoma is the most common form of oropharynx cancer in Sweden. Because the tumours produce so few symptoms, patients seek medical care when the disease is relatively advanced, often after the tumours have spread to the lymph glands of the throat, possibly making the prognosis much worse. It has long been known that smoking and drinking alcohol are the greatest risk factors of tonsil cancer.
More recent studies, however, have demonstrated a link between HPV and tonsil cancer, so that today an HPV infection is also one of the established risk factors. HPV is a virus that can cause skin warts and condyloma, and to date over a hundred different HPV types have been identified - some of which are therefore carcinogenic.
A research group at the medical university Karolinska Institutet has monitored people in the Stockholm County region who were diagnosed with tonsil cancer between 2003 and 2007. The results, which are published in the International Journal of Cancer, show that the rise in the number of tonsil cancer cases in the region is attributable to HPV infection. By analysing biopsies from 98 of the 120 patients, the researchers were able to show that 83 of the cases were HPV-positive, primarily as regards the virus type HPV16.
There are considerable differences between HPV-positive and HPV-negative tonsil patients. For example, people with HPV-positive tumours are roughly ten years younger when the disease is diagnosed, and they have a much better prognosis. Eighty-one per cent of the HPV-positive patients have a five-year survival rate, as opposed to 36 per cent of the HPV-negative patients. Since 1970, the cumulative incidence of HPV-positive tonsil cancer has increased from 23 to 93 per cent, while the number of HPV-negative tumours has decreased. Scientists believe that this latter effect is down to a corresponding drop in the number of smokers.
Professor Dalianis believes that if the trend continues, almost all tonsil cancer in the Stockholm region will be HPV-positive, just as it is with cervical cancer, for which 99.7 per cent of cases are HPV-positive.
"What we're seeing today is the result of infections that occurred roughly 20 years ago," she says. "The prognosis is obviously better for the HPV-positive patients, but the treatment is still arduous."
In light of this new knowledge, Professor Dalianis and her group now want to study how different types of treatment impact on the diagnosis and side-effects for HPV-positive and HPV-negative patients. They also hope to discover if the new HPV vaccine, which in Sweden will be given to all girls in between the ages of ten and twelve as of 2010, also protects against HPV infections in the oral cavity. The new HPV vaccine protects against HPV types 16 and 18.
Publication: "Incidence of human papillomavirus (HPV) positive tonsillar carcinoma in Stockholm, Sweden: An epidemic of viral-induced carcinoma?" Anders Näsman, Per Attner, Lalle Hammarstedt, Juan Du, Mathilda Eriksson, Geraldine Giraud, Sofie Ährlund-Richter, Linda Marklund, Mircea Romanitan, David Lindquist, Torbjörn Ramqvist, Johan Lindholm, Pär Sparen, Weimin Ye, Hanna Dahlstrand, Eva Munck-Wikland & Tina Dalianis, International Journal of Cancer, E-pub ahead of print feb 2009.
For further information, please contact:Professor Tina Dalianis
Further reports about: > Cancer > HPV > HPV vaccine > HPV-negative > HPV-positive > HPV-positive tonsil cancer > Karolinska Institutet > Stockholmer Water Prize 2009 > biopsies > human papillomavirus > lymph glands > oropharynx cancer > risk factor > tonsil cancer > tonsillar carcinoma > viral-induced carcinoma
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences