Two-year longitudinal study of parotid salivary flow rates in head and neck cancer patients receiving unilateral neck parotid-sparing radiotherapy treatment

Radiotherapy (RT) is a common treatment: for head and neck cancers, and fre quently causes permanent salivary dysfunction and xerostomia. This 2-year l ongitudinal study evaluated unstimulated and stimulated parotid flow rates in 11 patients with head and neck cancers who received unilateral neck paro tid-sparing RT. The results demonstrated that treated parotid glands had es sentially no output up to 2 years post-RT. Alternatively, spared parotid fl ow rates were indistinguishable from pre-RT values at I and 2 years post-RT , and increased slightly over time. Total unstimulated and stimulated parot id Bow rates 2 years after completion of RT were similar to pre-RT values, suggesting that spared parotid function may compensate for lost function fr om treated parotid glands. These results demonstrate that unilateral neck p arotid-sparing techniques are effective in preserving contralateral parotid glands up to 2 years after the completion of RT. (C) 1999 Elsevier Science Ltd. All rights reserved.