Phase I/II study of induction chemotherapy plus concurrent chemotherapy and SMART-IMRT-based radiotherapy in locoregionally-advanced nasopharyngeal cancer

This study aimed to evaluate the efficacy, toxicity and tolerability of simultaneous modulated accelerated radiation therapy (SMART)-intensity modulated radiotherapy (IMRT) plus cisplatin and 5-fluorouracil (5-FU) chemotherapy for patients with advanced nasopharyngeal cancer (NPC). Forty-five patients with stage II-IV NPC, determined by the American Joint Committee on Cancer system, were treated with prescribed doses of 72 Gy total to the gross tumor volume, 60 Gy to the clinical target volume and metastatic nodal station, and 54 Gy to the clinically-negative neck region. Before radiotherapy, two cycles of cisplatin (30 mg/m(2)/day on days 1-3) plus 5-FU (400 mg/m(2)/day on days 1-5) were delivered every three weeks for two cycles. Patients received two cycles of cisplatin (30 mg/m(2) day on days 1-3) every three weeks during radiotherapy. In addition, two cycles of cisplatin and 5-FU were given after radiation. All patients completed the prescribed radiotherapy and all scheduled cycles of chemotherapy. Thirty of the 45 patients (66.6%) had a complete response at the end of treatment. Grade 3 mucositis occurred in 4/45 patients (8.8%) and grade 3 dermatitis occurred in 5/45 (11.1%) during radiotherapy. Grade 3 neutropenia occurred in 6/45 (13.3%) during concurrent chemotherapy. There was no treatment-related mortality. After a median follow-up time of 51 months, only three patients' treatments had failed. Local and distant failure rates were 1.5 and 3.0%, respectively. SMART-IMRT plus cisplatin and 5-FU chemotherapy showed promising activity with manageable toxicity. It is a feasible regimen and improves locoregional disease control.