A precise glossectomy for tongue cancer adjacent to or crossing the midline: a novel anatomical unit resection surgery.

Previous studies have lacked a clear anatomical and functional definition of glossectomy for tongue cancer adjacent to or crossing the midline (TCML). The aim of this study was to provide a novel surgical approach based on anatomical unit resection surgery to treat TCML. A total of 120 patients with TCML who had undergone radical surgery were recruited retrospectively into the study. The patients who were treated with compartment surgery formed the control group; those treated with anatomical unit resection surgery formed the experimental group. The TCML was classified into cancer adjacent to the midline, cancer invading but not breaching the contralateral musculus verticalis linguae-genioglossus complex (MGC), and cancer breaching the contralateral MGC. No significant difference in the overall survival rate was found between the experimental and control groups overall (P = 0.853) or by TCML classification. In patients with cancer adjacent to the midline, the swallowing score (P = 0.040) and cosmetic outcome (P = 0.015) were significantly better in the experimental group than in the control group. For patients with cancer invading but not breaching the contralateral MGC, the speech intelligibility score (P = 0.001), swallowing score (P = 0.002), and cosmetic outcome (P = 0.037) were significantly better in the experimental group than in the control group. Anatomical unit resection surgery was found to provide a precise surgical treatment to address tongue cancer adjacent to or crossing the midline and maximally maintain tongue tissue and function.