Researchers at the University of Michigan (U-M) Health System have found a new indicator that may predict which patients with a common type of throat cancer are most likely have the cancer spread to other parts of their bodies (Head & Neck, January 13, 2012).
Patients with oropharyngeal squamous cell carcinoma who had "matted" lymph nodes -- nodes that are connected together -- had a 69% survival rate over three years, compared with 94% for patients without matted nodes.
The study tracked 78 cancer patients who were part of a clinical trial evaluating two cancer drugs in combination with intensity-modulated radiation therapy. All the patients had stage III or IV squamous cell carcinoma of the oropharynx and had not had any previous treatment. Sixteen of the 78 patients had matted nodes.
"The spread of cancer throughout the body accounts for about 45% of the deaths from oropharyngeal carcinoma," said senior study author Douglas Chepeha, MD, MSPH, an associate professor of otolaryngology head and neck surgery at the U-M Medical School. "Our findings may help doctors identify patients who are at higher risk for having their cancer metastasize and who would benefit from additional systemic therapy. Conversely, some patients without matted nodes may benefit from a reduction of the current standard treatment, which would cut down on uncomfortable side effects."
Notably, the findings indicate an increased risk independent of other established prognostic factors, such as the patient's history of smoking or whether they have the human papillomavirus (HPV), the researchers found. Smoking (tobacco and marijuana), heavy alcohol use, and HPV infection have each been linked to the development of oropharyngeal squamous cell carcinoma.
Matted nodes appear to be an especially strong indicator of increased risk among patients who are HPV-positive, even though HPV-positive patients had better overall outcomes than their HPV-negative peers. The patients with the best outcomes were HPV-positive nonsmokers.