Dr. Cohen Discusses Research Questions in Head and Neck Cancer

Ezra Cohen, MD, associate director, Moores Cancer Center at the University of California, San Diego, discusses remaining questions regarding the use of immunotherapy in head and neck cancer that still need to be addressed.

One of the remaining challenges with immunotherapy in head and neck squamous cell carcinoma includes patient selection, says Cohen. As it stands, little is known regarding which patient populations will respond to anti—PD-1 therapy, especially when agents are combined, he explains. Although PD-L1 expression in the tumor cells or the stroma is thought to be associated with greater chances of response to and benefit from this approach, the test is not perfect.

He adds that investigators need to acquire a stronger understanding of why patients are resistant or develop resistance to this form of therapy. As promising as immunotherapy is, only 15% of patients will show an initial response to this approach. For those patients, figuring out how to extend the durability is another dilemma, as approximately two-thirds of patients treated with anti—PD-1 therapy will not make it to 1 year, says Cohen. Finally, more research has to be devoted to understanding why the remaining 85% of patients do not show any response to immunotherapy.

For some of these patients, elements in the tumor microenvironment might be preventing the cancer from responding to PD-1, and investigators will have to find ways to address that, he adds. For other patients, the immune system might be failing to recognize the tumor cells, and investigators will need to find ways to overcome that challenge as well. Cohen believes that although the tools to overcome these hurdles may be available, more understanding is needed to inform how to use those tools effectively.