For patients with head and neck cancer, responses to treatment vary. Some do well with a combination of chemotherapy and radiation. Others have better outcomes with surgery.
The question for clinicians is how to make the right choice before treatment. New evidence suggests a patient's immune system may be a deciding factor.
Researchers from the University of Michigan Rogel Cancer Center looked at tumor tissue samples from 278 patients treated for head and neck cancer. The goal: to assess the number of tumor-infiltrating lymphocytes and determine whether that number corresponded with patient survival. Tumor-infiltrating lymphocytes are a type of immune cell found within a tumor.
The researchers counted the number of these immune infiltrates within each sample. They found that patients whose samples had a high number of immune cell infiltrates had significantly better survival rates than those with few infiltrates.
Matching the biology of a tumor to treatment is important for improving survival rates.Gregory T. Wolf, M.D.
When the researchers looked at the type of treatment patients received, they found different impacts. For patients who underwent chemoradiation, high levels of several specific subsets of immune infiltrates tied to significantly better survival rates. This was not the case for patients who had surgery, when all but one of those subtypes had an impact on survival.
"This study suggests we could potentially use characteristics of tumor-infiltrating lymphocytes to select patients for treatment — who might need chemoradiation and who should have their cancer cut out," says study author Gregory T. Wolf, M.D., professor and chair emeritus of otolaryngology – head and neck surgery at the University of Michigan Medical School.
Wolf leads the Head and Neck Specialized Program of Research Excellence (SPORE) grant at the University of Michigan Rogel Cancer Center. His team of researchers has collected tissue samples and followed up long term with about 1,800 patients who were treated for head and neck cancers.
Survival rates in head and neck cancer cases have not improved much in recent years, despite new therapy options. Researchers think that certain therapies may be helping some patients but hurting others. The challenge: how to direct the right therapy to the right patient to get the best outcome.
"Matching the biology of a tumor to treatment is important for improving survival rates," Wolf says. Traditionally, clinical features — the cancer's location or stage, for example — drove the decisions. Now, emerging tools and molecular markers are refining that decision matrix.
The study, published in Head & Neck, also found that the patients with more tumor infiltrates tended to be younger, nonsmokers and generally healthier.
Wolf is now leading an international trial that is underway to evaluate an immunotherapy treatment for patients with oral cavity cancer. Initial phase 2 trial results showed that the experimental immunotherapy regimen increased tumor infiltrates significantly, especially in patients who showed signs before surgery of their tumor shrinking. The study will accrue at up to 50 sites in the United States, Europe and South America. For information, call the U-M Cancer AnswerLine at 800-865-1125.