Influence of radiation dose to pharyngeal constrictor muscles on late dysphagia and quality of life in patients with locally advanced oropharyngeal carcinoma

BACKGROUND AND OBJECTIVE: Patients with oropharyngeal carcinoma (OPC) often have difficulty swallowing, which may affect quality of life (QoL). Radiation dose to constrictor muscles plays an important role. METHODS: 54 patients with locally advanced OPC were evaluated after intensity-modulated radiotherapy. Data were collected at standardized intervals using the EORTC questionnaires QLQ-C30 and QLQ-HN35 within two years. The pharyngeal constrictors (superior, middle, and inferior) were each contoured as an organ at risk. Influence of dose to the constrictors (>/=55 Gy vs. /=55Gy, 14 (64%) patients developed dysphagia grade /=3. At a dose of /=3. There was no dose-dependent difference in the severity of dysphagia in the acute phase (p= 0.989). There were differences 18 months after the end of RT: >/=55Gy: 19 (86%) patients showed dysphagia grade /=3. At /=3 (18 months: p = 0.001; 24 months: p= 0.000). Late dysphagia is also dependent on the dose level of the middle constrictor muscle (6 months: p= 0.000; 12 months: p= 0.005, 18 months: p= 0.034). After 24 months, there was no significant difference (p= 0.374). CONCLUSION: Radiation dose to the upper constrictor muscle appears to be of little relevance. The middle and lower constrictor should be given special consideration to avoid late dysphagia. Long-term QoL is independent on radiation dose.