Late-onset and relapsed cytokine release syndrome after nivolumab treatment in a patient with head and neck squamous cell carcinoma: a case report - Otsuka, Tomoyuki; Kojitani, Yoshiki; Imamura, Fumio; Fukutake, Junko; Nishio, Minako; Fujii, Takashi; Kudo, Toshihiro (Frontiers in Oncology, 2025)