Premium
Radiation dose to the masseter and medial pterygoid muscle in relation to trismus after chemoradiotherapy for advanced head and neck cancer
Author(s) -
Kraaijenga Sophie A.,
HammingVrieze Olga,
Verheijen Sonja,
Lamers Emmy,
Molen Lisette,
Hilgers Frans J.,
Brekel Michiel W.,
Heemsbergen Wilma D.
Publication year - 2019
Publication title -
head and neck
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.012
H-Index - 127
eISSN - 1097-0347
pISSN - 1043-3074
DOI - 10.1002/hed.25573
Subject(s) - trismus , medicine , head and neck cancer , radiation therapy , nuclear medicine , complication , pterygoid muscles , logistic regression , temporomandibular joint , surgery , dentistry
Background We studied the relationship between trismus (maximum interincisor opening [MIO] ≤35 mm) and the dose to the ipsilateral masseter muscle (iMM) and ipsilateral medial pterygoid muscle (iMPM). Methods Pretreatment and post‐treatment measurement of MIO at 13 weeks revealed 17% of trismus cases in 83 patients treated with chemoradiation and intensity‐modulated radiation therapy. Logistic regression models were fitted with dose parameters of the iMM and iMPM and baseline MIO (bMIO). A risk classification tree was generated to obtain optimal cut‐off values and risk groups. Results Dose levels of iMM and iMPM were highly correlated due to proximity. Both iMPM and iMM dose parameters were predictive for trismus, especially mean dose and intermediate dose volume parameters. Adding bMIO, significantly improved Normal Tissue Complication Probability (NTCP) models. Optimal cutoffs were 58 Gy (mean dose iMPM), 22 Gy (mean dose iMM) and 46 mm (bMIO). Conclusions Both iMPM and iMM doses, as well as bMIO, are clinically relevant parameters for trismus prediction.