Speech and swallowing after surgical treatment of advanced oral and oropharyngeal carcinoma: a systematic review of the literature

Purpose of this review is the evaluation of speech and swallowing function after surgical treatment for advanced oral and oropharyngeal carcinoma. A systematic literature search (1993-2009), yielding 1,220 hits. The predefined criteria for inclusion in this systematic review were oral or oropharyngeal cancer, surgical treatment, speech and/or swallow function outcome, T-stage a parts per thousand yen 2, patient cohort > 20, adequate description of the patient cohort in terms of tumor (sub) site, and low risk of bias (Cochrane criteria). Twelve studies fulfilled the predefined criteria. The results for speech more than 1 year after resection of oral or oropharyngeal cancer are reported to be moderate to good; although in the majority of patients speech is experienced as deviant. Overall sentence intelligibility scores are normal (92-98%). Swallowing is reported to be often already disturbed before treatment and is even more severely compromised after treatment. Aspiration rates of liquids vary from 12 to 50% and especially after oropharyngeal resection, pharyngeal transit times are delayed. Postoperative radiotherapy further increases function disturbances significantly. Critical subsites with regard to speech are the mobile tongue, and the soft palate and for swallowing, the floor of the mouth, the posterior base of tongue and the hard and soft palate. Prosthetic appliances (e.g., obturators, palatal augmentation prostheses) can diminish function losses considerably. Surgery for oral and oropharyngeal cancer yields function deficits, most notably with regard to swallowing. Series are small and outcome measurements vary. Therefore, to optimize pre-operative risk assessment, there is a need for internationally standardized outcome measurements.