Page 103 - Functional impairment and cues for rehabilitation of head and neck cancer patients -

Long-term function after CRT and preventive rehabilitation
DISCUSSION
Given the increasing survival rates of patients treated for HNC, due to changing etiology and continuously improving treatment strategies, knowledge of long-term functional outcomes had gained importance (19). This is the first study to report on functional outcomes and quality of life of patients more than ten years after IMRT with concurrent chemotherapy for HNC combined with preventive rehabilitation exercises, which is quickly becoming current practice at a rising number of institutes. In our cohort, objective swallowing problems were minimal, with slight deterioration compared to the results at six-year follow-up assessment. None of the evaluable patients at ten-year plus follow-up were feeding tube dependent, consumed a modified diet (FOIS < 7) or had suffered from pneumonia since the six-year follow-up. However, subjective swallowing related quality of life moderately worsened according to SWAL-QOL scores. None of the patients had or perceived trismus. Subjective and objective voice and speech related outcomes stayed more or less stable from six- to ten-year follow-up. Overall quality of life remained at a high level, according the EQ-VAS assessment, although a third of the patients experienced at least some pain or discomfort. The results suggest that with current practice, including IMRT and preventive rehabilitation exercises, the functional outcomes and quality of life of patients surviving more than ten are reasonably well-maintained.
The worsening observed in, predominantly subjective, functional outcomes might be caused by multiple factors. Firstly, ageing likely plays a role in the deterioration of swallowing (efficiency), and speech, function over time (44). Multiple studies have shown that older individuals have less effective swallowing function compared to younger adults (45). Secondly, late treatment effects such as neuropathy and continuing fibrosis of swallowing muscles are a known cause of late functional problems after radiotherapy for HNC (21, 22). The mechanism of this continuing fibrosis is probably based on a continuous (over)production of factors activating wound healing, which continues until long after the initial radiotherapy (22). Also, since the resolution of the videofluoroscopy studies was better at ten-year follow up, minimal aspiration might have been missed at six-year follow-up. There were some discrepancies between subjective and objective outcomes. For example, the median MIO decreased with 6 mm between six- and ten-year plus follow-up which did not result in any of the patients with either clinical trismus or perceived trismus. The four patients with perceived trismus at the six-year mark, did not perceive their mouth opening as decreased while either mouth opening was stable (n = 2) or decreased (n = 2). This might be due to a very gradual decrease in median MIO which enables habituating to and coping with the new situation. This was not true, however, for swallowing; the moderately deteriorated swallowing related quality of life as measured by the SWAL-QOL was not accompanied by worsened objective measures, which stayed stable or even improved. This might be because subjective measures are more sensitive to small deteriorations in swallowing function than objective measures.
Some earlier studies have investigated long-term functional outcomes after CRT. Kraaijenga et al. published ten-year results of a historical cohort treated with CRT for HNC at our institute
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