Pegaspargase Combined with Concurrent Radiotherapy for Early‐Stage Extranodal Natural Killer/T‐Cell Lymphoma, Nasal Type: A Two‐Center Phase II Study

BACKGROUND: Concurrent chemoradiotherapy (CCRT) is expected to improve local and systemic disease control and has been established as a standard therapy for several types of solid tumors. Considering the benefits of frontline radiation and pegaspargase in localized extranodal natural killer (NK)/T‐cell lymphoma, nasal type (ENKTL), we conducted a phase II study on pegaspargase‐based CCRT to explore an effective treatment. MATERIALS AND METHODS: In this study, 30 patients with newly diagnosed nasal ENKTL in stages IE to IIE received CCRT (radiation 50 Gy and two cycles of pegaspargase 2,500 unit/m(2) every 3 weeks). Four courses of pegaspargase were performed after CCRT. RESULTS: The patients completed CCRT and four cycles of pegaspargase. The complete remission (CR) rate was 90%, with a 95% confidential interval (CI) of 73.5%–97.9% after CCRT. The CR rate was 100% (95% CI, 88.4%–100%) at the end of the treatment. The 2‐year overall survival and progression‐free survival rates were 90.9% (95% CI, 78.4%–100%) and 92.8% (95% CI, 83.2%–100%), respectively. The major adverse events were in grades 1–2. CONCLUSION: Preliminary data indicate that pegaspargase combined with concurrent radiotherapy for newly diagnosed patients with nasal ENKTL was efficacious and well tolerated. Registered at www.chictr.org. Clinical Trial Registration Number. ChiCTR‐OIC‐15007662. IMPLICATIONS FOR PRACTICE: This clinical trial, evaluating the efficacy and toxicity of concurrent chemoradiotherapy by using single‐drug pegaspargase for patients with extranodal natural killer/T‐cell lymphoma, nasal type (ENKTL) in stage IE to IIE, showed pegaspargase combined with concurrent radiotherapy was efficacious and well tolerated. Pegaspargase has a long half‐life and is easy to administer via intramuscular injection. Consequently, pegaspargase combined with concurrent radiotherapy for patients with ENKTL can be completed in the outpatient clinic.