| Aim: This project focuses primarily on the assessment of ototoxicity in patients with tumors in the head and neck, treated with a combination of radiation and cisplatinum according to the RADPLAT-protocol. Parts of this study are dose-effect relationships and patterns of recovery after treatment. An additional issue is the value of otoacoustic emissions that possibly can be used to increase the sensitivity of monitoring the status of hearing, detecting ototoxicity in an earlier phase, and reducing the patient load. Method: The project consists of the following parts: Retrospective analyses of ototoxicity in patients treated according to the RADPLAT-protocol. This concerns a group of 75 patients treated in 6 different hospitals. In these patients a series of 5 audiometric tests is available and the analysis focuses on specific patterns of damage. In the same group the dose-effect relationship will be investigated and the project aims to separate the effects of cisplatinum and radiation. The added value of otoacoustic emissions in monitoring ototoxicity is still unclear from literature. OAEs may be able to increase the sensitivity in detecting ototoxicity and reduce the load of audiological examinations for the patient. The added value and additional advantages will be investigated in different patient groups in the AMC. Also we will investigate the sensitivity, the reliability, and the reproducibility of different types of OAE measurements. In a new group of 250 patients treated according to the RADPLAT-protocol cisplatinum will be delivered at randomly according to different protocols. The results will be evaluated by means of OAE-measurements. A third group of patients receives a relatively low dose of cisplatinum, but according to a more frequent delivery scheme. The effects of this alternative delivery will be evaluated using tone audiometry and OAE measurements. The patients from the retroprospective and prospective studies who showed hearing damage will be followed as far as possible post treatment in order to find information about the long-term effects. Long-term effects can be influenced by delayed expression of damage due to the cisplatinum and radiation. On the other hand some recovery may show up. First results: The results of 146 patients who received conventional audiometry and high frequency audiometry have been analysed. From this study some characteristic patterns in short-term damage appear to be presented. Future research: The results from the RADPLAT patients will be analysed in detail and presented as manuscripts in peer-reviewed journals. The inclusion of patients for the prospective part of this study will continue. This work will be described in the PhD thesis of Drs. C.L. Zuur. |
