In a Chinese phase III trial reported in JAMA, Tang et al found that radiotherapy alone was noninferior to concurrent chemoradiotherapy in failure-free survival in patients with low-risk nasopharyngeal carcinoma.
In the open-label multicenter trial, 341 patients were randomly assigned between November 2015 and August 2020 to receive intensity-modulated radiation therapy (IMRT) alone at 68 to 70 Gy in 2.0 to 2.2 Gy fractions given once per day 5 days per week (n = 172) or IMRT with concurrent cisplatin at 100 mg/m2 every 3 weeks for three cycles. Low-risk disease was defined as stage II/T3N0M0 without adverse features (all nodes < 3 cm, no level IV/Vb nodes, no extranodal extension, Epstein-Barr virus DNA < 4,000 copies/mL).
The primary endpoint was 3-year failure-free survival, with a noninferiority margin of 10%.
Median follow-up was 46 months (interquartile range = 34–58 months). Failure-free survival at 3 years was 90.5% in the radiotherapy-alone group vs 91.9% in the chemoradiotherapy group (difference = −1.4%, 1-sided 95% confidence interval [CI] = −7.4% to ∞, P < .001 for noninferiority). The adjusted hazard ratio was 1.36 (95% CI = 0.70–2.66, P = .85).
At 3 years, overall survival was 98.2% vs 98.6% (difference = −0.4%, 95% CI = −3.1% to 2.3%, P = .31), locoregional relapse–free survival was 94.0% vs 94.3% (difference = −0.3%, 95% CI = −5.3% to 4.7%, P = .43), and distant metastasis–free survival was 95.8% vs 97.6% (difference = −1.8%, 95% CI = −5.6% to 2.0%, P = .22).
Grade 3 or 4 adverse events occurred in 17% of patients in the radiotherapy group vs 46% of the chemoradiotherapy group (P < .001), including leukopenia (1% vs 10%), neutropenia (2% vs 7%), nausea (1% vs 13%), vomiting (1% vs 15%), anorexia (5% vs 29%), weight loss (1% vs 5%), and mucositis (10% vs 19%). Late grade 3 or 4 toxicity occurred in 4% vs 2% of patients (P = .48). No treatment-related deaths were reported.
The radiotherapy alone group had significantly better scores during radiotherapy on the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire QLQ-C30, including in the domains of global health status, social functioning, fatigue, nausea and vomiting, pain, insomnia, appetite loss, and constipation.
The investigators concluded, “Among patients with low-risk nasopharyngeal carcinoma, treatment with IMRT alone resulted in 3-year failure-free survival that was not inferior to concurrent chemoradiotherapy.”
Jun Ma, MD, of the Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, is the corresponding author for the JAMA article.
Disclosure: The study was supported by the National Natural Science Foundation of China, Natural Science Foundation of Guangdong Province, and others. For full disclosures of the study authors, visit jamanetwork.com.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.