Effective clearance of inhaled particles requires mucus production and continuous mucus transport from the lower airways to the oropharynx. Mucus production takes place mainly in the peripheral airways. Mucus transport is achieved by the action of the ciliated cells that cover the inner surface of the airways (mucociliary transport) and by expiratory airflow. The capacity for mucociliary transport is highest in the peripheral airways, whereas the capacity for airflow transport is highest in the central airways. In patients with airways disease, mucociliary transport may be impaired and airflow transport may become the most important mucus transport mechanism.
MULTIFILE
Purpose / objective: Head and neck cancer patients treated with chemoradiation are at risk for developing trismus (reduced mouth opening). Trismus is often a persisting side-effect and difficult to manage. It impairs eating, speech and oral hygiene, affecting quality of life. Although several studies identified the masseter muscle (MM) as one of the main organs at risk, currently this structure is rarely considered during treatment planning. Prospective studies for chemoradiation are lacking. The aim of our study was to quantify the relationship between radiation dose to the MM and development of radiation-induced trismus in an IMRT-VMAT population. Results: At the first evaluation, 6-12 weeks post-treatment, fourteen patients had developed radiation-induced trismus (15%). On average, mouth opening decreased with 4.1 mm, or 8.2 % relative to baseline. Mean dose to the ipsilateral MM was a stronger predictor for trismus than mean dose to the contralateral MM, as indicated by the lowest -2 log likelihood (Table 1). Figure 1A shows the correlation between the ipsilateral mean masseter dose and the relative decrease in mouth opening, with trismus cases indicated in red. No trismus cases were observed in 33 patients (35%) with a mean dose to the ipsilateral MM < 20 Gy. The risk of trismus in the other 60 patients (65%) increased with higher mean doses to the ipsilateral MM. Figure 1B shows the fitted NTCP curve as a function of the mean dose, with a TD50 of 55 Gy. The actual incidence (with 1 SE) of trismus cases within 5 dose bins is indicated as well, showing a good correspondence with the NTCP fit with a relatively large uncertainty in the dose area > 50 Gy. Patients with tumors located in the oropharynx were at highest risk.
The background and purpose of this paper is to investigate adherence, exercise performance levels and associated factors in head and neck cancer (HNC) patients participating in a guided home-based prophylactic exercise program during and after treatment [swallowing sparing intensity modulated radiation therapy (SW-IMRT)]. Fifty patients were included in the study. Adherence was defined as the percentage of patients who kept up exercising; exercise performance level was categorized as low: ≤1, moderate: 1–2, and high: ≥2 time(s) per day, on average. Associations between 6- and 12-week exercise performance levels and age, gender, tumour site and stage, treatment, intervention format (online or booklet), number of coaching sessions, and baseline HNC symptoms (EORTC-QLQ-H&N35) were investigated. Adherence rate at 6 weeks was 70% and decreased to 38% at 12 weeks. In addition, exercise performance levels decreased over time (during 6 weeks: 34% moderate and 26% high; during 12 weeks: 28% moderate and 18% high). The addition of chemotherapy to SW-IMRT [(C)SW-IMRT] significantly deteriorated exercise performance level. Adherence to a guided home-based prophylactic exercise program was high during (C)SW-IMRT, but dropped afterwards. Exercise performance level was negatively affected by chemotherapy in combination with SW-IMRT.
