The rate of grade 2 and grade 3 dysphagia among patients with head and neck cancer is determined by patient age, disease site, and the mean radiation dose administered to the total constrictor muscle volume, according to a study published in Clinical Cancer Informatics.1
Dysphagia is a frequently occurring toxicity experienced by patients with head and neck cancer who receive chemoradiation — particularly to the pharyngeal constrictor muscles and supraglottic and glottic larynx — but there is a lack of data elucidating the dose threshold before dysphagia occurs.
For this study, researchers assessed the outcomes of 424 patients with oropharyngeal, nasopharyngeal, hypopharyngeal, or laryngeal cancer who received modern intensity modulated radiotherapy and chemotherapy.
The median follow-up was 33.3 months. Grade 2 or worse dysphagia was observed in 9.7% of patients and grade 3 or worse dysphagia was observed in 5.2% of patients. The mean doses to the total constrictor muscle ranged from 30.1 to 85.7 Gy (median, 61.2 Gy). A 3.4% increase in the predicted rate of grade 2 or worse dysphagia per Gy was observed.
The mean threshold total constrictor doses resulting in less than a 5% rate of grade 2 or greater and grade 3 or greater dysphagia were lower than 58 Gy and 61 Gy, respectively.
The authors concluded that “[t]he ability to calculate personalized probability of late dysphagia in these patients would be valuable in facilitating treatment planning as well as for clinicians to identify a subset of patients with increased risk of late dysphagia for early intervention.”
- Tsai CJ, Jackson A, Setton J, et al. Modeling dose response for late dysphagia in patients with head and neck cancer in the modern era of definitive chemoradiation. JCO Clin Canc Informatics. 2017 Nov 7. doi: 10.1200/CCI.17.00070 [Epub ahead of print]