To investigate the feasibility of intensity-modulated radiation therapy (IMRT) with or without chemotherapy, and to assess toxicities, failure patterns, and survivals in patients with nasopharyngeal carcinoma (NPC).

Radiation consisted of 70 Gy given to the planning target volumes of primary tumor plus any N+ disease and 59.4 Gy given to subclinical disease, delivered over 33 treatment days. Patients with stage T2b or greater or with N+ disease also received concurrent cisplatin (100 mg/m(2)) on days 1, 22, and 43 followed by adjuvant cisplatin (80 mg/m(2)) on day 1; fluorouracil (1,000 mg/m(2)/d) on days 1 through 4 administered every 4 weeks for three cycles. Tumor, clinical status, and acute/late toxicities were assessed. The primary objective was to test the transportability of IMRT to a multi-institutional setting.

Between February 2003 and November 2005, 68 patients with stages I through IVB NPC (of which 93.8% were WHO types 2 and 3) were enrolled. Prescribed IMRT (target delineation) was given to 83.8%, whereas 64.9% received chemotherapy per protocol. The estimated 2-year local progression-free (PF), regional PF, locoregional PF, and distant metastasis-free rates were 92.6%, 90.8%, 89.3%, and 84.7%, respectively. The estimated 2-year PF and overall survivals were 72.7% and 80.2%, respectively. Acute grade 4 mucositis occurred in 4.4%, and the worst late grade 3 toxicities were as follows: esophagus, 4.7%; mucous membranes, 3.1%; and xerostomia, 3.1%. The rate of grade 2 xerostomia at 1 year from start of IMRT was 13.5%. Only two patients complained of grade 3 xerostomia, and none had grade 4 xerostomia.

It was feasible to transport IMRT with or without chemotherapy in the treatment of NPC to a multi-institutional setting with 90% LRPF rate reproducing excellent reports from single institutions. Minimal grade 3 and lack of grade 4 xerostomia were encouraging.