Reirradiation with intensity-modulated radiotherapy for locally recurrent T3 to T4 nasopharyngeal carcinoma.

BACKGROUND: The purpose of this study was to assess the efficacy and toxicities of reirradiation using intensity-modulated radiotherapy (IMRT) in patients with locally advanced recurrent nasopharyngeal carcinoma (NPC). METHODS: Thirty-eight patients with consecutive rT3 to rT4 NPC treated between 2005 and 2013 were retrospectively analyzed. RESULTS: The 3-year overall survival (OS), progression-free survival (PFS), and local control rate were 47.2%, 17.5%, and 44.3%, respectively. Gross target volume (GTV) D95 , GTV D50 , and age were all important prognostic factors for OS and PFS, but only GTV D95 was an important determinant for local control. A total of 73.7% patients experienced ≥1 grade 3 late toxicities and 3 patients died of massive epistaxis. Temporal lobe necrosis (TLN) developed sooner with a higher total biological equivalent dose. CONCLUSION: Adequate tumor dose coverage was important for treating rT3 to rT4 NPC. Although late complications were common, treatment-related mortality was solely vascular in nature. Dose constraints of neurologic structures for reirradiation should be revised with the latest information on late toxicities. © 2016 Wiley Periodicals, Inc. Head Neck 39: 533-540, 2017.