T4a classification for oral cancer using mandibular canal invasion instead of bone marrow invasion in the TNM staging system. - Okura M; Yamakawa N; Otsuru M; Hasegawa T; Yokota Y; Rin S; Sakai H; Yamada SI; Hirai E; Ashikaga Y; Yamamoto K; Ueda M; et al. (Oral oncology, 2025)