Dysphagia and trismus after concomitant chemo-Intensity-Modulated Radiation Therapy (chemo-IMRT) in advanced head and neck cancer; dose–effect relationships for swallowing and mastication structures

Abstract

General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Prospective assessment of dysphagia and trismus in chemo-IMRT head and neck cancer patients in relation to dose-parameters of structures involved in swallowing and mastication. Material and Methods:Assessment of 55 patients before, 10-weeks (N=49) and 1-year post-treatment (N=37). Calculation of dose-volume parameters for swallowing (inferior (IC), middle (MC), and superior constrictors (SC)), and mastication structures (e.g. masseter). Investigation of relationships between dose-parameters and endpoints for swallowing problems (videofluoroscopy-based laryngeal Penetration-Aspiration Scale (PAS), and study-specific structured questionnaire) and limited mouth-opening (measurements and questionnaire), taking into account baseline scores. Results:At 10-weeks, volume of IC receiving ≥60Gy (V60) and mean dose IC were significant predictors for PAS. One-year post-treatment, reported problems with swallowing solids were significantly related to masseter dose-parameters (mean, V20, V40 and V60) and an inverse relationship (lower dose related to a higher probability) was observed for V60 of the IC. Dose-parameters of masseter and pterygoid muscles were significant predictors of trismus at 10-weeks (mean, V20, and V40). At 1-year, doseparameters of all mastication structures were strong predictors for subjective mouth-opening problems (mean, max, V20, V40, and V60). Conclusions:Dose-effect relationships exist for dysphagia and trismus. Therefore treatment plans should be optimized to avoid these side effects.

Trismus in oral cancer patients undergoing surgery and radiotherapy

“…17 Althogh a few authors state that restriction of mouth opening may occur even at low doses of irradiation, 18 a steep dose effect relationship between radiation dose to the masticatory apparatus and trismus has been noted. 19,20 The high incidence of trismus in our study can be attributed to the use of external beam radiotherapy because trismus with conventional radiotherapy is reported to be 25.4%. It is only 5% for those given intensity modulated radiotherapy as patients treated with brachytherapy received a lower dose in masticatory muscles.…”

Risk structures for radiation-induced trismus in head and neck cancer

“…Possible confounding factors, such as dose from brachytherapy, were accounted for in our analyses and predicted trismus rates by our models were in corresponded well with the observed rates. In line with others, we based our analyses on mean absorbed structure doses as this dose metric have been reported suitable to describe relationships between various mastication structures and trismus [7][8][9][10][11]. Acknowledging that DVH points typically are strongly correlated, it is not likely that investigating other dose or volume metrics for our purpose of identifying critical structures for radiation-induced trismus would have altered the presented results substantially.…”

“…Other studies have also suggested that dose to the masseter is associated with a higher risk of trismus [8,9,11]. In particular, both Lindblom et al [8] and, and more recently, Rao et al [9] found dose to the ipsilateral masseter muscle to provide superior statistics in predicting trismus (defined by Risk structures receiving substantial dose from brachytherapy (more than a maximum absorbed doses of 3.0 Gy or more than mean absorbed doses of 2.0 Gy) were excluded from analysis of that specific structure.…”

“…Irradiation of the temporomandibular joint (TM joint) and muscles of mastication, especially doses to the masseter and the pterygoid muscles, have been reported to be associated with radiation-induced trismus [7][8][9][10][11]. However, available data diverge as to which anatomical structure is more critical for trismus after RT in HNC.…”

Trismus and reduced quality of life in patients with oral squamous cell carcinoma, who received post-operative radiotherapy alone or combined with chemotherapy

“…The risk for trismus is also increased when the masticator and lateral pterygoid muscles are included in the radiation field, in patients with advanced stage of disease, and with chemoradiotherapy [6,9−11]. Furthermore, patients with oral carcinoma, who receive post-operative radiotherapy have increased risk for trismus, which is related to the fibrosis of masticator muscles due to radiotherapy and due to fibrosis related to the surgical management of tumour [10,12,13].…”