Impact of Radiation Dose on Pharyngeal Structures for swallowing in Oropharyngeal Carcinoma

Introduction:

The relationship between radiation dose and functional impairment in head and neck cancer is well known. Impairment of swallowing function is especially important for patients with pharyngeal carcinoma. Until now there are no cut-off values defined, which describe impaired swallowing function related to radiation dose.

Material and Methods:

101 patients who were treated for oropharyngeal cancer from 4/2012 – 10/2014 were retrospectively analyzed. Self-assessment of swallowing function and use of feeding tube data were collected with the "OncoFunction" aftercare tool. The pharyngeal structures were segmented from the radiation planning CT scans and the dose volume was calculated for relevant structures.

Results:

We could demonstrate a significant correlation between radiation dose and impairment of swallowing function for the Mm. constrictores and the cricopharyngeal muscle. Patients who received more than 45 Gy on the cricopharyngeal muscle had a significant (p < 0,05) worse swallowing function than those who received less than 45 Gy. ROC-analyses (p < 0,05) also demonstrated a significant impact of radiation dose for the Mm. constrictores. Especially in patients with combined adjuvant chemoradiation the impairment of swallowing was obvious related to the radiation dose.

Discussion:

The data show a significant correlation between radiation doses on swallowing organ at risk and impaired swallowing function. Cut-off values for the radiation dose were determined.

Publication History

Publication Date:
18 April 2018 (online)