In a Chinese phase III study reported in JAMA Oncology, Dai et al found that induction chemotherapy followed by radiotherapy alone was noninferior in terms of progression-free survival vs induction chemotherapy followed by concomitant chemoradiotherapy in the first-line treatment of locoregionally advanced nasopharyngeal carcinoma.
Study Details
In the multicenter open-label trial, 383 patients with stage III to IVB disease were randomly assigned between April 2015 and March 2018 to receive induction chemotherapy followed by radiotherapy (n = 193) or chemoradiotherapy (n = 190). Induction chemotherapy consisted of three cycles of cisplatin at 60 mg/m2 and docetaxel at 60 mg/m2 on day 1 and continuous infusion of fluorouracil at 600 mg/m2 on days 1 to 5 every 21 days. Patients then received either radiotherapy alone or with cisplatin at 30 mg/m2 weekly for 6 to 7 weeks.
The primary endpoint of the trial was 3-year progression-free survival, with a noninferiority margin of 10% for the upper limit of the 95% confidence interval for the difference between the radiotherapy group vs chemoradiotherapy group.
Key Findings
Median follow-up was 76 months (interquartile range = 70–89 months). Progression-free survival rate at 3 years was 76.2% with radiotherapy vs 76.8% with chemoradiotherapy, a difference of 0.6% (95% confidence interval [CI] = –7.9% to 9.1%, P = .01 for noninferiority). The hazard ratio was 0.92 (P = .66).
At 3 years, overall survival rate was 86.0% vs 86.8% (hazard ratio [HR] = 0.95, P = .82), locoregional metastasis–free survival rate was 91.3% vs 88.5% (HR = 0.80, P = .42), and distant metastasis–free survival rate was 83.7% vs 85.1% (HR = 1.06, P = .81). The noninferiority criterion was met for each of these endpoints.
Grade 3 or 4 adverse events during treatment were observed in 54% of patients in the radiotherapy group vs 73% of those in the chemoradiotherapy group, most commonly neutropenia (38% vs 38%), leukopenia (21% vs 36%), and vomiting (11% vs 19%). No differences in late toxicity were observed between the groups.
The investigators concluded: “The results of this randomized clinical trial suggest that after induction chemotherapy for locoregionally advanced nasopharyngeal carcinoma, radiotherapy alone was noninferior to chemoradiotherapy in terms of 3-year progression-free survival.”
Wei Jiang, PhD, of the Department of Radiation Oncology, Affiliated Hospital of Guilin Medical University, Guilin, China, is the corresponding author of the JAMA Oncology article.
Disclosure: The study was supported by the Natural Science Foundation Key Projects of Guangxi, National Natural Science Foundation of China, and others. For full disclosures of the study authors, visit jamanetwork.com.
