Depth of response may predict clinical outcome in patients with recurrent/metastatic head and neck cancer treated with pembrolizumab-containing regimens oleh Ken Saijo, Ken Saijo, Hiroo Imai, Hiroo Imai, Kota Ouchi, Kota Ouchi, Keiju Sasaki, Keiju Sasaki, Yuya Yoshida, Yuya Yoshida, Yoshifumi Kawamura, Yoshifumi Kawamura, Sakura Taniguchi, Sakura Taniguchi, Yuki Kasahara, Yuki Kasahara, Keigo Komine, Keigo Komine, Hidekazu Shirota, Hidekazu Shirota, Masanobu Takahashi, Masanobu Takahashi, Chikashi Ishioka, Chikashi Ishioka