Page 202 - Functional impairment and cues for rehabilitation of head and neck cancer patients -

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Chapter 8
of a tube lowers the risk for prolonged dependency. Thus, even if prehabilitation would not fully mitigate the risk, postponing tube placement still might result in shorter dependency durations.
Prehabilitation includes the improvement of patients’ baseline outcomes between diagnosis and start of treatment in order to prevent or minimalize post treatment impairments (45). Several studies on other cancer types have investigated this strategy and found positive results on body mass and overall physical strength and function (31, 32). In HNC patients receiving CRT, studies have been performed on preventive swallowing exercises before or during treatment to improve swallowing function (46-48). These interventions showed positive effects on post treatment swallowing function.
In order to optimize muscle mass and function prior to treatment to prevent functional impairment, a multifactorial approach to resolve the modifiable factor sarcopenia would be most effective (49). Firstly, increase in muscle strength and mass should be provoked by means of exercises. These exercises ideally include targeted swallowing exercises, preferably with progressive load, to increase swallowing muscle function, as well as overall physical exercises to increase overall muscle strength and mass (50). One has to keep in mind, however, that the time period between diagnosis and start of treatment is short and may be too short to effectively build up muscle mass – if possible, exercises should therefore be continues during treatment. Secondly, patients should be encouraged to adhere to a high protein diet to facilitate muscle growth. Patients treated in our institute, independently of their muscle mass, are advised to increase their protein intake to at least 1.5 g/kg a day. Therefore, as part of prehabilitation, patients should be advised to alter their diet (e.g., consuming protein in portions of 25-30 gram per meal) and prescribing high-protein medical nutrition to supplement their regular meals should be considered (51, 52). Considering the high prevalence of dysphagia in HNC patients before treatment, altering the route of administration using a (temporary) feeding tube could be considered and might be the only way to reach the minimal protein intake of 1.5 g/kg a day to optimize nutritional status. Eventually, the combination of high protein intake and (targeted) exercises might break the vicious spiral of muscle function loss and malnutrition and thus long-term functional outcomes might be improved. However, PEG probe placement as a back-up is not recommended since it is associated with substantial risks for patients who will eventually not need the tube. These risks can be avoided by close monitoring of the patient and placement of a tube when necessary.
A remaining uncertainty in this study, due to its retrospective nature, is that some variables which arguably could confound the association of sarcopenia with tube dependency were not available. In particular, health literacy, the degree to which someone is able to understand information to make health decisions, might be a confounding factor unaccounted for (see figure 1). Also, analyses were performed on a subgroup of HNC patients treated with CRT, and the conclusions may be generalizable to this specific population only. Future studies are needed to confirm the association in more heterogeneous HNC populations. Finally, we estimated