Immune Systems Impact Immunotherapy Effectiveness in Head and Neck Cancer
Specific immune cells surrounding tumors may play a crucial role in how patients with head and neck cancer respond to nivolumab immunotherapy, according to research presented at the American Association of Cancer Research annual meeting (April 1-5, 2017; Washington, DC).
In a previous trial, the immunotherapy nivolumab demonstrated significant effectiveness in improving survival with limited adverse side effects in patients with platinum-refractory, recurrent squamous cell carcinoma of the head and neck. However, treatment with nivolumab was not equally effective in all patients. Researchers believed that immune system profiles may have been a factor that contributed to these varied responses.
Robert Ferris, MD, PhD, chief of the Division of Head and Neck Surgery, co-leader of the Cancer Immunology Program, University of Pittsburgh Cancer Institute (PA), and colleagues furthered this study to assess whether differences in the patients’ immune system profiles could have any association with varied responses to immunotherapy treatment. A focus of the further study involved tumor-associated immune cells, which are cells that have infiltrated the tumor and are believed to be critical proponents of tumor growth.
Researchers found that increased levels of tumor-associated immune cells expressing the programmed death-ligand 1 (PD-L1) protein were associated with greater survival odds and greater likelihood of response to nivolumab. Additionally, after examining blood samples received prior to immunotherapy initiation, researchers found that patients with higher levels of circulating CD8-positive T cells and lower levels of regulatory T cells were associated with better response to nivolumab.
Researchers believe that their findings may play a significant role in determining optimal immunotherapy treatment options for patients with platinum-refractory, recurrent squamous cell carcinoma of the head and neck in the future.
“By determining the nature of these cells and how they are affected by treatments, we may be able to significantly improve the effectiveness of current therapies and help a greater number of patients," said Dr Ferris in a press release (April 2, 2017). – Zachary Bessette