Extended Course and Increased Dose of Initial Chemotherapy for Extranodal Nasal Type Natural Killer/T (NK/T)-Cell Lymphoma in Patients <60 Years Old: A Single-Center Retrospective Cohort Study

Optimal Courses of Chemotherapy Combined with Radiotherapy for Low-Risk Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type: A Propensity Score Matching Analysis

Purpose

This retrospective study compared effectiveness between ≤4 cycles and ≥5 cycles of L-asparaginase/pegaspargase-based chemoradiation in newly diagnosed low-risk extranodal natural killer/T-cell lymphoma (ENKTL), nasal type classified according to the Prognostic Index of Natural Killer (PINK) lymphoma model.

Patients and Methods

Patients were categorized into ≤4-cycle (2–4 chemotherapy cycles, n = 166) and ≥5-cycle groups (5–6 cycles, n = 86). Propensity score matching analysis was used to reduce potential confounding bias between the two groups. Treatment responses, adverse events, and survival outcomes between the two groups were analyzed.

Results

No matter before or after matching (65 in the ≤4-cycle group, 65 in the ≥5-cycle group), response rates and survival outcomes were similar between the ≤4-cycle and ≥5-cycle groups. Incidences of grade 1–2 anemia and transaminase elevation were higher in the ≥5-cycle group. After matching, for stage IE disease, there were no differences in response rates and survival outcomes between the two groups. For stage IIE disease, the complete response rate was higher in the ≥5-cycle group (72.4% vs 92.6%, p = 0.049), and the 3-year overall survival (65.5% vs 85.2%, p = 0.024) and 3-year progression-free survival (58.6% vs 81.5%, p = 0.027) rates were significantly extended in the ≥5-cycle group.

Conclusion

When chemoradiotherapy strategies with L-asparaginase/pegaspargase-based regimens are applied to modern low-risk ENKTL patients classified according to the PINK model, it may be better to moderately extend chemotherapy courses in patients with stage IIE disease.

Short-Course Versus Long-Course Chemoradiotherapy for Stage IE-IIE Extranodal Natural Killer/T cell Lymphoma, Nasal Type: A Multicenter Retrospective Study

Background

This study compared clinical outcomes and adverse events between L-asparaginase/pegaspargase-based short-course and long-course chemoradiotherapy in newly diagnosed stage IE–IIE extranodal natural killer/T cell lymphoma, nasal type (ENKTL).

Material/Methods

Patients were categorized into a short-course (2–4 chemotherapy cycles, median: 4, n=153) and long-course group (5–6 cycles, median: 6, n=83). The chemotherapy regimens included GELOX, SMILE, and VLP. The radiotherapy dose was 40–63 Gy (median: 55 Gy). Adverse events, treatment responses, and survival outcomes between the 2 groups were compared.

Results

Ann Arbor stage IIE and short-course chemotherapy adversely affected overall survival (OS). Ann Arbor stage IE favorably affected progression-free survival (PFS). Grade 3–4 hematological toxicities were higher in the long-course group (25.3% vs. 14.4%, p=0.038). Ann Arbor stage was the single different clinical feature between the 2 groups, and independently affected survival outcomes. In subgroup analysis of stage IE, there was no difference in response rates and survival outcomes between the 2 groups. In subgroup analysis of stage IIE, the recurrence and death rates were significantly lower in the long-course group (6.1% vs. 23.2%, p=0.015; 12.2% vs. 39.3%, p=0.002; respectively), and the 3-year OS and PFS rates were much longer in the long-course group (87.8% vs. 62.5%, p<0.001; 83.7% vs. 57.1%, p=0.001; respectively).

Conclusions

When radiotherapy was combined with L-asparaginase/pegaspargase-based chemotherapy to treat early-stage ENKTL patients, 2–4 cycles of chemotherapy might be sufficient for stage IE patients, while stage IIE patients might require 5+ cycles.