Combination of gemcitabine, l-asparaginase, and oxaliplatin (GELOX) is superior to EPOCH or CHOP in the treatment of patients with stage IE/IIE extranodal natural killer/T cell lymphoma: a retrospective study in a cohort of 227 patients with long-term follow-up

Optimal treatment strategies for localized extranodal natural killer/T cell lymphoma (ENKTL) have not been fully defined. We retrospectively compared the efficacy and safety of combined gemcitabine, l-asparaginase, and oxaliplatin (GELOX) (n = 38), continuous infusion of etoposide, vincristine and doxorubicin, with cyclophosphamide and prednisone (EPOCH) (n = 54), or combined cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) (n = 135) as induction chemotherapy in patients who were newly diagnosed with stage I/II ENKTL. After induction chemotherapy, the complete response (CR) rate and overall response rate (ORR) for the GELOX group were significantly higher than those in the EPOCH group (68.4 vs. 42.6 %, P = 0.011 for CR and 86.8 vs. 68.5 %, P = 0.038 for ORR). Both EPOCH and GELOX groups can attain much higher CR rates than CHOP group (CR rate was 31.8 %, P < 0.05). The 3-year overall survival (OS) and progression-free survival (PFS) rate were significantly better in GELOX group than in EPOCH or CHOP group (87.0 vs. 54.0 vs. 54.0 % for OS, P < 0.05; 72.0 vs. 50.0 vs. 43.0 % for PFS, P < 0.05). However, no significant differences were found between EPOCH and CHOP groups in OS or PFS (P = 0.765 for OS, and 0.421 for PFS). The safety profiles were acceptable in all three groups. In conclusion, GELOX is superior to EPOCH or CHOP in the treatment of patients with stage I/II ENKTL. Further clinical trials of ENKTL should use asparaginase-based regimens as the standard chemotherapy.