Intensity-Modulated Radiation Therapy Without Concurrent Chemotherapy for Stage IIB Nasopharyngeal Cancer

Abstract

To evaluate the treatment outcome of patients with stage IIB nasopharyngeal carcinoma (NPC) after definitive intensity-modulated radiotherapy (IMRT) without concurrent chemotherapy. Between August 2003 and December 2006, 107 patients with T1N1M0 (8%), T2N0M0 (13%), or T2N1M0 (79%) NPC were definitively treated with IMRT. Sixty-one received IMRT only, and 46 patients had various strategies of systemic treatment, consisting of abbreviated neoadjuvant (38 patients), concurrent (8 patients), or adjuvant (16 patients) chemotherapy. Radiation doses prescribed to the planning tumor volume of the gross disease, high-risk clinical tumor volume, and low-risk clinical tumor volume were 66 to 70 Gy, 54 to 60 Gy, and 50-54 Gy, respectively. With a median follow-up of 39 months (range, 7-77 months), 6 patients had locoregional relapse: 1 local only, 1 locoregional, and 4 regional only. Five patients had distant failure. Five of 6 total deaths were cancer related. The 3-year estimated local control, regional control, metastasis-free survival, disease-free survival, and overall survival were 96.5%, 98%, 94.8%, 90.7%, and 95.8%, respectively. No significant difference in treatment outcome was demonstrated in patients treated with or without chemotherapy of any schedule. IMRT without concurrent chemotherapy provides good outcome for patients with stage IIB NPC with acceptable toxicity. Neoadjuvant chemotherapy did not appear to provide significant additional benefit for this patient subgroup. Further investigation in the prospective setting is warranted to explore the role of systemic agents in the treatment of NPC with limited primary disease and cervical lymphadenopathy when IMRT is used.