Page 14 - Functional impairment and cues for rehabilitation of head and neck cancer patients -

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Chapter 1
Despite the effort put into minimalizing the toxicity of treatment in combination with the optimization of individualized training programs, the impaired function of the head and neck area is still an important issue in the lives of HNC survivors, suggesting considerable room for further improvement. For this reason, research efforts have been made in the NKI-AVL over the last one and a half decade, with the aim to unravel the remaining clinical and physiological questions behind the functional losses related to HNC.
First, van der Molen et al. performed a randomized controlled trial (RCT) comparing two types of rehabilitation strategies (with and without the addition of the medical tool/training device TheraBite®) to prevent (long-term) side effects of CRT for HNC (figure 2). The TheraBite® device enables performing passive range of motion exercises that appeared to improve mouth opening as well as swallowing function in a comfortable position (figure 2) (35-37). The hypothesis was that with a dedicated exercise program using the TheraBite®, trismus, swallowing, and speech problems in HNC patients treated with CRT could be better prevented than with a standard exercise program. However, comparing the results of the two arms of this RCT no significant differences were found. Nevertheless, the preventive rehabilitation program with the addition of the TheraBite® was feasible with good compliance, and in comparison with historical controls of a preceding in-house study that included patients who did not receive any preventive rehabilitation suggested that there were benefits of both forms of preventive rehabilitation on functional limitations at one-year post-treatment. Additionally, a cost-effectiveness study indicated that the addition of the TheraBite® to the rehabilitation program was cost-effective compared to exercises alone (38). Studies on preventive rehabilitation from other institutes showed predominantly positive results, although meta-analysis could not be performed due to the heterogeneity of outcome measures and a statistically significant effect could not be detected in the Cochrane Review by Perry et al. (39). The lack of convincing evidence is not necessarily due to the lack of observed effectiveness, however, but partially due to limited precision caused by the small sample sizes of the included studies.
Kraaijenga et al. further built on the results of van der Molen et al., by assessing functional outcomes of the study participants, six years after inclusion in the aforementioned RCT. Results showed that the positive effects of the preventive rehabilitation program were maintained. Compared to the ten-year results of the historical cohort of patients who did not receive preventive rehabilitation, the patients who had received preventive rehabilitation had maintained better functional outcomes (40).
Despite the positive outcomes provided in the studies by van der Molen et al. and Kraaijenga et al., inevitably, several clinical, methodological, and physiological questions remained deserving further research. Especially given the increased survival of patients treated for HNC, due to improving treatment strategies and changing etiology (i.e., more HPV-associated cases and thus younger patients being affected), a better understanding of long-term functional outcomes is gaining relevance (41). Besides, earlier studies have suggested that functional impairment after (C)RT may develop, or continue to worsen, even years after the end of treatment. This is possibly due to a combination of ageing, continuing fibrosis of swallowing