Tongue Strength as a Predictor of Functional Outcomes and Quality of Life after Tongue Cancer Surgery

Abstract

Surgical resection of oral cancer can result in altered speech, swallowing, and quality of life (QOL). To date, the oral outcome variables of tongue strength, tongue and jaw range of motion, and saliva production have not been extensively assessed. This pilot study was done to assess tongue strength along with other oral outcomes and their relationship to performance status for speech, swallowing, and QOL after partial glossectomy. Our aim was to create a norm for what should be considered a normal tongue strength value in this population. We hypothesized that patients with tongue strength of 30 kPa or greater would perform better on the performance status scale and various QOL measures than do patients with tongue strength of less than 30 kPa. We used a cross-sectional design in this study. The postoperative assessment included 1) Performance Status Scale and Karnofsky Performance Status Scale; 2) oral outcome variables of tongue strength, jaw range of motion. and saliva production; and 3) patient-rated QOL ratings via Eating Assessment Tool, M. D. Anderson Dysphagia Inventory, EORTC-H&N35, and Speech Handicap Index. Patients with tongue strength of at least 30 kPa performed better on the performance status scales and various QOL measures. The cutoff score of 30 kPa for tongue strength measures revealed a trend in predicting performance on the scales and QOL measures. The oral outcome variables correlated with performance status for speech, swallowing, and QOL. We propose a norm for tongue strength in this population, based on the trend seen in this group of patients, as none previously existed. Future studies are under way that incorporate a larger sample size to further validate this norm. Future studies will also examine oral functional outcome measures in a larger population by inclu'ding other oral and oropharyngeal sites to help predict speech and swallow performance status and QOL.