Purpose: To explore the efficacy and safety of L-asparaginase in newly-diagnosed extranodal nature killer (NK)/T -cell lymphoma (ENKTL), we conducted a prospective phase II study of L-asparaginase, cyclophosphamide, vincristine, doxorubicin and dexamethasone (CHOP-L) regimen in combination with radiotherapy.
Patients and methods: Patients with newly diagnosed ENKTL and an ECOG performance status of 0 to 2 were eligible for enrollment. Treatment included 6-8 cycles of CHOP-L (cyclophosphamide, 750 mg/m(2) day 1; vincristine, 1.4 mg/m(2) day 1 (maximal dose 2 mg), doxorubicin 50 mg/m(2) day 1; dexamethasone 10 mg days 1-8; L-asparaginase 6000 u/m(2) days 2-8). Radiotherapy was scheduled after 4-6 cycles of CHOP-L regimen, depending on stage and primary anatomic site. The primary endpoint was complete response (CR) rate.
Results: A total of 38 eligible patients were enrolled. The median age was 40.5 years (range, 15 to 71 years). Their clinical characteristics were male to female ratio, 24:14; Ann Arbor stage I, 20; II, 11; III, 3; IV, 4. CR and overall response rates were 81.6% (95% CI, 69.3% to 93.9%) and 84.2%, respectively. With a median follow-up of 25 months, the 2-year overall survival, progression-free survival and disease-free survival rates were 80.1% (95%CI, 73.3% to 86.9%), 81% (95%CI, 74.5% to 87.5%) and 93.6% (95%CI, 89.3% to 97.9%), respectively. The major adverse events were myelosuppression, liver dysfunction, and digestive tract toxicities. Grade 3 to 4 leukopenia and neutropenia were 76.3% and 84.2%, respectively. No treatment-related death was observed.
Conclusion: CHOP-L chemotherapy in combination with radiotherapy is a safe and highly effective treatment for newly diagnosed ENKTL.