Advance directives and powers of attorney for patients with head and neck cancer - frequency and availability as well as reasons for and against their creation - Allner, M; Gostian, M; Balk, M; Rupp, R; Sarina, Müller; Traxdorf, M; Iro, H; Gostian, AO (Laryngo-Rhino-Otologie, 2021)