Volume and Location of the Defect as Predictors of Swallowing Outcome After Glossectomy: Correlation with a Classification

Abstract
This study aimed to characterize the swallowing outcomes after glossectomy and analyze factors affecting them. An attempt is made to propose a classification system and corroborate it to the results. This is a cross-sectional study to assess swallowing in carcinoma tongue patients treated surgically with or without reconstruction, followed by adjuvant therapy as indicated. One hundred and six patients were evaluated with videofluoroscopy (VFS). Volume defects were classified as I: less than one-third, II: one-third to half, III: half to two-thirds, IV: two-thirds to total glossectomy. Location was assigned as lateral, tip, and sulcus defects. Predictors were T stage, surgical approach, volume, location, and adjuvant radiotherapy. Chi-square and logistic regression were used for statistical analysis. Defects were Class I, II, III, and IV in 36, 42, 16, and 12 patients, respectively. Adjuvant radiotherapy was given in 40% of cases. Mean evaluation time was 14 months from treatment. On, Functional Oral Intake Scale (FOIS) score, as the Class of the defect increased, the percentage of patients with low scores (poor swallowing outcomes) showed an increasing trend (p < 0.001). Defect volume, T stage, approach, and radiotherapy correlated significantly with an abnormality of all VFS parameters (p < 0.001). On multivariate analysis, defect volume remained an independent predictor for oral parameters; radiotherapy emerged as the only independent predictor for pharyngeal parameters. The incremental volume of the defect is a significant independent predictor of swallowing. Based on this, we propose a classification for glossectomy.