Does radiation dose to the salivary glands and oral cavity predict patient-rated xerostomia and sticky saliva in head and neck cancer patients treated with curative radiotherapy?

Background and Purpose: To investigate the association between the mean salivary gland and oral cavity dose, with patient-rated moderate and severe xerostomia and sticky saliva. Patients and methods: One hundred and fifty-seven patients treated with bilateral irradiation for head and neck cancer were included. The parotid and submandibular glands and the oral cavity were delineated on plannings-CT scans. At baseline and 6 and 12 months self-reported xerostomia and sticky saliva were assessed using the EORTC QLQ-H&N35 questionnaire. Results: At 6 months a significant association between the mean parotid (MDpar) and mean submandibular dose (MDsubm) and xerostomia was observed (OR-MDpar: 1.17; P=0.002 and OR-MDsubm: 1.08; P=0.02). Between MDpar and MDsubm, a significant interaction term was present. No significant association was found with the oral cavity dose. Xerostomia was reversible depending on MDpar and MDsubm Considering Sticky saliva, a significant association was found at 6 and 12 months with MDsubm (OR: 1.03; P Conclusions: Both MDpar and MDsubm influence the risk of xerostomia in irradiated patients at 6 months. This probability as a function of the mean parotid dose significantly depended on the mean dose in the submandibular glands. Sticky saliva mainly depends on MDsubm. (c) 2005 Elsevier Ireland Ltd. All rights reserved.