Temporal patterns of patient-reported trismus and associated mouth-opening distances in radiotherapy for head and neck cancer: A prospective cohort study

Abstract

Objectives: To identify temporal patterns of patient-reported trismus during the first year post-radiotherapy, and to study their associations with maximal interincisal opening distances (MIOs).

Design: Single institution case series.

Setting: University hospital ENT clinic.

Participants: One hundred and ninety-six subjects who received radiotherapy (RT) for head and neck cancer (HNC) with or without chemotherapy in 2007-2012 to a total dose of 64.6/68 Gy in 38/34 fractions, respectively. All subjects were prospectively assessed for mouth-opening ability (Gothenburg Trismus Questionnaire (GTQ), European Organization for Research and Treatment of Cancer quality of life Questionnaire (EORTC QLQ-H&N35), and MIO) pre-RT and at 3, 6 and 12 months after RT.

Main outcome measures: Correlations between temporally robust GTQ symptoms and MIO as given by Pearson's correlation coefficients (P_r ); temporally robust GTQ-symptom domains as given by factor analysis; rates of trismus with respect to baseline by risk ratios (RRs).

Results: Four temporally robust domains were identified: Eating (3-7 symptoms), Jaw (3-7), Pain (2-5) and Quality of Life (QoL, 2-5), and included 2-3 persistent symptoms across all post-RT assessments. The median RR for a moderate/severe (>2/>3) cut-off was the highest for Jaw (3.7/3.6) and QoL (3.2/2.9). The median P_r between temporally robust symptoms and MIO post-radiotherapy was 0.25-0.35/0.34-0.43/0.24-0.31/0.34-0.50 for Eating/Jaw/Pain/QoL, respectively.

Conclusions: Mouth-opening distances in patients with HNC post-RT can be understood in terms of associated patient-reported outcomes on trismus-related difficulties. Our data suggest that a reduction in MIO can be expected as patients communicate their mouth-opening status to interfere with private/social life, a clinical warning signal for emerging or worsening trismus as patients are being followed after RT.

Keywords: outcomes < General; quality of life < General.

Figure 1

Relative risks and 95% confidence intervals for the temporally robust Gothenburg Trismus Questionnaire (GTQ) items across 3/6/12 months after radiotherapy relative to baseline for ≥moderate (upper; orange dots), and ≥severe symptom cut-off (lower; red dots) severity. Note: ** p≤0.0001; * p≤0.05

Figure 2

Pearson’s correlation coefficient (P_r) between each of the 21 Gothenburg Trismus Questionnaire (GTQ) items and MIO at 3/6/12 months post-radiotherapy (post-RT). Note: The color coding on the left hand side follows that of the P_r scale on the right hand side.