Patients with oropharynx cancers caused by infection with the Human Papilloma Virus (HPV) fare dramatically better than those whose disease stems from non-viral factors such as alcohol and tobacco use, say researchers from Dana-Farber Cancer Institute.
In one study, the five-year survival rate of patients with oropharynx cancers (back of tongue and tonsils) related to HPV infection was 82 percent, compared with 35 percent for patients without HPV infection, according to data presented at the annual meeting of the American Society of Clinical Oncology in Chicago.
“This enormous difference between HPV-positive and HPV-negative patients is mainly because the virally caused disease is biologically different, and also somewhat because those patients tend to be younger and healthier,” says Marshall Posner, MD, director of Head and Neck Oncology at Dana-Farber and the study’s lead author.
“Our therapy of sequential induction chemotherapy followed by chemoradiotherapy is highly effective in these patients, and the good results are maintained for years,” Posner adds.
Most oropharynx and other cancers of the head and neck have been blamed on excessive alcohol and tobacco use, but in the past 25 years an increasing number of cases have been attributed to HPV, a sexually transmitted virus that also causes cervical cancer.
The Dana-Farber researchers have been involved in a review of such patients compared to those with traditional risk factors treated as part of a large cooperative study started in 1999.
The data in the current abstract is a subset of the larger trial, which was reported in 2007 in The New England Journal of Medicine. The abstract includes outcome and other data on 111 patients with OPC (oropharynx cancer), half of them infected with HPV virus and the other half virus-free.
Posner says the studies have shown that HPV-associated oropharynx cancer differs in at least two major ways. One, the virus itself is relatively sensitive to chemotherapy, causing the cancer cells to die; and, second, the DNA of the HPV-infected cancer cells is less severely damaged than in cells exposed to tobacco and alcohol.
The HPV-infected patients also tend to be younger and healthier, enabling them to withstand treatment and fight the cancer better, Posner said.
Because oropharynx cancer in these patients is so much more treatable, Posner and other Dana-Farber investigators believe they can reduce the dosage of radiation used in treatment, which could prevent some of the most disabling long-term side effects. They have launched a study seeking an answer to this question.
Other authors of the abstract are Robert Haddad, MD, and Jochen Lorch, MD, MSc, Dana-Farber; Olga Goloubeva, PhD, MSc, Ming Tan, PhD, Lisa Schumaker, and Kevin Cullen, MD, University of Maryland Greenebaum Cancer Center, Baltimore; and Nicholas Sarlis, MD, PhD, sanofi-aventis, Bridgewater, NJ.
The research was funded by sanofi-aventis and the Steven Tendrich Fund for Head and Neck Cancer Research.