The purpose of this research study is to test the safety and the benefit of adding
pembrolizumab (a therapy that activates the immune system to fight cancer) to standard of
care treatment for head and neck cancer. The standard of care treatment will include surgery
followed by radiation for 6 weeks. Some patients may also receive cisplatin as standard of
care once a week for 6 weeks if the cancer is found to be "high risk". High risk includes
cancer that was not completely removed (positive margins) or cancer that has invaded through
the outer lining of your lymph nodes.