The aim of this study was to analyze the clinical results of our adaptive radiation therapy scheme of a two-step intensity-modulated radiotherapy (IMRT) method for nasopharyngeal cancer (NPC) at Kinki University Hospital.
Between 2000 and 2007, 35 patients with Stage I-IVB NPC treated by IMRT were included. For all patients, treatment-planning computed tomography was done twice before and during IMRT to a total dose of 60-70 Gy/28-35 fractions (median 68 Gy). Chemotherapy (cisplatin 80 mg/m(2)/3 weeks x 1-3 courses) was given concurrently with IMRT for 31 patients.
The 3- and 5-year overall survival rates for the 31 patients treated with concurrent chemotherapy were 88% and 83%, respectively. The 3- and 5-year loco-regional control rates for the 31 patients were 93% and 87%, respectively. Planning target volume delineation for the primary site or involved nodes was insufficient for three early cases, resulting in marginal recurrence in the three patients (9%). Except for one patient with early death, xerostomia scores at 1-2 years were: Grade 0, 11; Grade 1, 17; Grade 2, 5; Grade 3, 1.
Excellent overall survival and loco-regional control rates were obtained by a two-step IMRT method with concurrent chemotherapy for NPC, although marginal recurrence was noted in some early cases.