Page 213 - Functional impairment and cues for rehabilitation of head and neck cancer patients -

placement during (C)RT for HNC. One approach is a reactive tube placement strategy in which patients only receive a feeding tube when unacceptable weight loss, dehydration, or aspiration occur during treatment. A benefit of this approach is that oral intake is maintained as long as possible, preventing non-use atrophy of the swallowing musculature. The only pitfall of this approach is that the patient should be carefully monitored on an almost daily basis. The other approach is to use a prophylactic strategy, in which all patients receive a feeding tube, which might better prevent unacceptable weight loss, dehydration, and aspiration, and with that – in some cases – interruption of the (chemotherapy) treatment. Another advantage of the prophylactic placement would be that frequent monitoring the patient is less demanding. The obvious drawback is that non-use atrophy of the swallowing musculature, which is a prelude to long-term swallowing impairment, is more likely to occur. This is especially unfortunate when patients who could have managed without a tube do get one, unnecessarily increasing their risk for function loss and complications associated with tube placement. To facilitate this discussion, we developed a prediction model to estimate the risk for prolonged feeding tube dependency with the aim to enable selection of high-risk patients for ‘proactive’ feeding tube placement (Chapter 7) (12). Risk factors included the simple and clinically readily available parameters T-stage, BMI, and pretreatment weight loss and dysphagia. The estimated risk enables informed and shared decision making on the timing of feeding tube placement in individual patients, trading off the risk of weight loss/dehydration versus the risk of loss of (swallowing) function. Future research should reveal whether clinical decision making with aid of this prediction tool indeed results in less functional loss after treatment, especially when feeding tube placement is combined with (SEA-based) preventive swallowing rehabilitation exercises.
Prediction models are best developed based on consistently observed and strong predictors, in order to precisely estimate the individual risk for tube feeding. Such predictors are not only useful for the previously mentioned purpose of selecting patients for proactive tube feeding, but – when modifiable – could also serve as a clue for strategies to improve function and minimize the risk of poor outcome. Not all risk factors and possible predictors for feeding tube dependency have been identified or studied in depth. One interesting candidate predictor is pretreatment sarcopenia. Therefore, we explored the association of pretreatment sarcopenia, i.e., loss of skeletal muscle mass, with prolonged feeding tube dependency (Chapter 8) (13). We hypothesized this association might exist because patients with sarcopenia have limited reserves with regard to muscle mass and function, and therefore would be more prone to develop swallowing problems than patients with an adequate skeletal muscle mass to begin with. Results of our study, in which we measured skeletal muscle mass on the level of C3 on routine CT imaging prior to treatment, revealed a strong association between lower pretreatment muscle mass and a higher risk for prolonged feeding tube dependency. Thus, skeletal muscle mass measurement prior to treatment should be considered as additional predictor for feeding tube dependency, and can improve the clinical prediction model. A suggestion for clinical use of the model with muscle mass measurement is illustrated in figure 1 and further discussed in the future perspective section below. Pre-treatment sarcopenia also seems to be associated with other functional limitations, such as trismus and speech/voice
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