IPSILATERAL PAROTID SPARING STUDY IN HEAD AND NECK-CANCER PATIENTS WHO RECEIVE RADIATION-THERAPY - RESULTS AFTER 1 YEAR

Objective. To determine if three-dimensional treatment planning and co nformational dose delivery could minimize radiation dose and salivary gland dysfunction to contralateral parotid glands in patients with uni lateral head and neck cancers. Study design. Fifteen patients with uni lateral head and neck cancers were treated with three-dimensional trea tment planning. Unstimulated and stimulated bilateral parotid saliva w as collected before radiotherapy, weekly during treatment, and 1, 3, 6 , and 12 months after the completion of radiotherapy. Results. Treated parotid glands received an average dose of 4949 cGy, whereas spared g lands received only 355 cGy. Unstimulated and stimulated parotid flow rates decreased dramatically in treated glands after the initiation of radiotherapy and were significantly lower at 1 year after radiotherap y compared with baseline. Conversely, parotid flow rates in spared gla nds underwent mild changes during radiotherapy and were similar at 1 y ear after radiotherapy compared with baseline. Conclusion. Parotid gla nd function can be preserved for at least 1 year in patients with unil ateral head and neck cancers with three-dimensional treatment planning .