Treatments for oropharyngeal cancer can have some serious side effects. Surgery can be quite extensive and, in some cases, disfiguring. Patients may have difficulty chewing, swallowing or talking. Chemotherapy can cause hair loss, nausea, vomiting, mucositis (inflammation of the mucus membranes) and weakening of the immune system. Radiation therapy can lead to mucositis, gum problems, loosening of the teeth, dry mouth, problems with swallowing and changes in taste.
Gregory Wolf, M.D., a Head and Neck Surgeon with the University of Michigan, says two-thirds of oropharyngeal cancer patients are already in advanced stages at the time of diagnosis. They often need extensive surgery and/or other treatments that have a significant impact on their quality of life. But treatments don’t always match outcomes. Some large tumors can be successfully shrunk with radiation therapy. On the other hand, some very small areas of cancer are quite aggressive and need comprehensive therapy.
Currently, there is no way to tell how a cancer will respond to treatment. But researchers appear to be making headway on some important clues, using markers from the cancer cells as a basis for treatment decisions. At the University of Michigan Comprehensive Cancer Center, researchers are looking at how cancers with specific tumor markers respond to different therapies. Investigators want to find out if those markers may predict which cancers will be the most aggressive and what kinds of treatment may have the most effective results. During pre-treatment biopsy, investigators took samples of the tumor and looked for various markers.
One of the markers under study is HPV-16 (human papilloma virus), a virus also associated with risk for cervical cancer. Research Scientist, Thomas Carey, Ph.D., says they have found non-smoking patients with the HPV marker tended to respond very well to treatment. Response rates are lower in smokers and women with HPV markers in their tumors.
Another marker is called epidermal growth factor receptor (EGFR), a protein on the surface of cells that controls cell growth. Patients with this marker also tended to respond very poorly to treatment. A third marker is p53, a gene which controls cell growth and death. It normally suppresses tumor growth. Patients with a "wild type" of p53 and high levels of a protein related to cell survival tended to respond very poorly to chemotherapy.
Investigators just published the results of their study in the online version of Journal of Clinical Oncology on May 12. Further research needs to be done. However, if the tumor markers prove to be valid, doctors may be able to use the information to determine which patients need more aggressive treatment and what kinds of therapy or drugs may work best against the cancer.