Long-Term Survival After Cisplatin-Based Induction Chemotherapy and Radiotherapy for Nasopharyngeal Carcinoma: A Pooled Data Analysis of Two Phase III Trials

Abstract

Purpose To evaluate the long-term outcome in patients with nasopharyngeal carcinoma (NPC) treated with induction chemotherapy and radiotherapy (CRT) versus radiotherapy alone (RT). Patients and Methods The data from two phase III studies comparing CRT with RT in NPC were updated and pooled together for analysis. A total of 784 patients were included for analysis, with an equal number of patients in both arms. Induction chemotherapy consisted of two to three cycles of cisplatin, bleomycin, and fluorouracil, or cisplatin and epirubicin. RT was given to the nasopharynx and neck using megavoltage radiation (median dose, 70 Gy). The median follow-up time for surviving patients was 67 months. Analysis was based on intention to treat. Results The addition of induction chemotherapy to RT was associated with a decrease in relapse by 14.3% and cancer-related deaths by 12.9% at 5 years. The 5-year relapse-free survival rate was 50.9% and 42.7% in the CRT and RT arm, respectively (P = .014), and the 5-year disease-specific survival rate was 63.5% and 58.1% in the CRT and RT arm, respectively (P = .029). The 5-year overall survival rate was 61.9% and 58.1% in CRT and RT arm, respectively (P = .092). The incidence of locoregional failure and distant metastases was reduced by 18.3% and 13.3% at 5 years, respectively, with induction chemotherapy. There was no significant difference in the treatment failure patterns between the two arms. Conclusion The addition of cisplatin-based induction chemotherapy to RT was associated with a modest but significant decrease in relapse and improvement in disease-specific survival in advanced-stage NPC. However, there was no improvement in overall survival.