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 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.