Page 210 - Functional impairment and cues for rehabilitation of head and neck cancer patients -

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Chapter 9
study suggested that surgery is associated with less swallowing impairment compared to radiotherapy, although the difference was not statistically significant (Chapter 2) (1). In this cohort, more than half of the patients treated with surgery alone underwent postoperative radiotherapy, which nullified the benefit of surgery regarding favorable swallowing outcomes. After performing this study, results of the randomized ORATOR-trial were published comparing surgery (plus neck dissection) and radiotherapy (with or without chemotherapy) for oropharyngeal carcinoma (2). The authors concluded that there were no clinically meaningful differences with regards to the swallowing-related quality of life, but that there was a difference with respect to toxicity profiles (e.g., more mucositis in the radiotherapy group and more trismus in the surgery group). It can be concluded that when selecting oropharyngeal cancer patients for either surgery or radiotherapy, these different toxicity profiles have to be taken into account and should be matched with the patient’s preferences. Also, physicians should try to select those patients for surgery as single-modality treatment who most likely will not need adjuvant radiotherapy, to avoid additional functional impairment caused by multimodality treatment.
Numerous methods for evaluation of swallowing function are available (3). In several studies, objective measures of functional outcomes do not reflect subjective experience of those functions. In our study on long-term functional outcomes ten-years plus after CRT and preventive rehabilitation (described in Chapter 4), this was observed as well (4). None of the patients with objectively measured trismus (mouth opening < 36 mm) perceived their mouth opening as impaired. In contrast, decreased perceived swallowing function, as assessed with the SWAL-QOL questionnaire, was not accompanied by decreased objective swallowing, as assessed by videofluoroscopy. These discrepancies between objective and subjective measures probably have several causes. First, habituation to and acceptance of functional loss may lead to self-reported measures within the normal range, despite deviating objective measures, a phenomenon known as response shift (5). Second, some measures might be more sensitive to change than others. For example, the score of a questionnaire on swallowing function might decrease several points when swallowing speed slightly decreases e.g., it will take more time to finish a meal, while videofluoroscopy might be less sensitive to this change in speed. This also suggests the third possible cause. Aspects of the particular function measured by means of an objective assessment method might not be (the most) relevant for patients’ daily functioning and therefore change in currently available objective measures might not ultimately lead to change in the subjective measure. This discrepancy might lead to problems with regard to selection of patients for interventions in the context of rehabilitation.
This discrepancy between subjective and objective swallowing measures can confront clinicians with challenging dilemmas. For example, how are objective disorders, silent aspiration for example, best treated when the patient perceives the swallowing function as normal? But also, how is a perceived disorder best treated when it cannot be objectified? In this thesis, we tried to contribute to the solution to the dilemmas, by introducing a new objective measure for swallowing on the ICF-level of capacity (Chapter 3). The current objective swallowing methods measure the physical function needed for eating and drinking