Poster 418, Language: GermanHey, Jeremias/Gerlach, Reinhard/Kuhnt, Thomas/Gernhardt, Christian RalfAfter radiation treatment of head and neck cancer quality of life and pathological changes in oral health are significantly dependent on functional insufficiency of salivary glands. Satisfactory therapies for treating resulting diseases such as xerostomia, radiation caused dental decay and osteoradionecrosis have not yet been found.
New strategies aim at containing these side effects without reducing radiation dose. We test protectionary effects of 3dimensional conformal radiation therapy (3D-CRT) including medicamentary treatment using radioprotector and contralateral parotid gland sparing.
Using a sample of 106 patients under radiation treatment of head and neck cancer we measured changes of pH-value, salivary flow rates and buffer capacity to analyse the protectionary effects of Amifostin in contrast to contralateral parotid gland sparing. A cumulative dose of between 64Gy - 70Gy was given to primary planning target volume.
Exact measurement of the radiation dose was achieved by using CT-based dose-volume-histograms. We extracted salivary before, during and after radiation treatment as well as one six and twelve month after radiation. Based on salivary flow rates we tested the protection of salivary glands/normal tissue compliance probability of Parotiden by Amifostin and contalateral parotid gland sparing controlling for the amount of radiation given.
The best protection in these experiments was found with contralateral parotid gland sparing by using modern 3D-CRT. Although Amifostin offers some protection, too, it is less effective and due to high costs and considerable side effects not suitable for routine treatments.
The study was supported by a research grant of Deutsche Krebshilfe.
Keywords: Radiotherapie, Speicheldrüsenschonung, Amifostin, Speichel