RESUMEN
PURPOSE: The authors sought to define toxicity patterns according to the different accrual periods and clinical-therapeutic features in a large series of nasopharyngeal cancer (NPC) patients treated in two Italian centres over more than two decades. MATERIALS AND METHODS: A total of 883 patients consecutively treated with radiotherapy from 1977 to 2000 at the Florence (FLO) and Brescia (IRA) radiation oncology centres were studied. The crude incidence of late treatment toxicity in the different subgroups of patients was calculated and compared. RESULTS: Higher total and fractional doses and the "older" treatment techniques were related with an increased incidence of the main late effects of treatment. More recently treated patients experienced less treatment-related complications. CONCLUSIONS: Results of this benchmark study may have implications for understanding and developing new radiotherapy techniques, such as three-dimensional conformal radiotherapy (3D-CRT) and, in particular, intensity-modulated radiotherapy (IMRT) for NPC patients.