Treatment modality and prognostic analysis of early stage nasal NK/T cell lymphomas / 中华放射肿瘤学杂志

ABSTRACT

Objective To investigate the prognosis of patients with nasal NK/T cell lymphoma receiving different treatment modalities. Methods From 1990 to 2004, 85 patients with stage ⅠE and ⅡE primary nasal NK/T cell lymphomas were retrospectively studied. Twenty patients received chemotherapy of CHOP regimen alone, 11 patients received radiotherapy only, 6 patients received radiotherapy followed by more than 2 cycles of chemotherapy, and 48 patients received more than 2 cycles of chemotherapy followed by radiotherapy. Survival analysis was performed by the Kaplan-Meier method, the difference between groups was evaluated by the Log-rank test, and the Cox regression model was used for multivariate analysis. Results The 5-year overall survival rate (OS) was 40%. The 5-year OS was 57% and 28% for limited stage ⅠE and extended stage ⅠE(X2 =8. 87, P =0. 003), and 23% for stage ⅡE, which was similar to extended stage ⅠE (X2 =0. 19, P-0. 664). The 5-year OS was 13%, 54% and 47% for chemotherapy alone, radiotherapy followed with or without chemotherapy, and chemotherapy followed by radiotherapy, respectively. The last two groups had better OS than chemotherapy alone (P = 0. 030 and 0.049). The 5-year OS was 58% and 12% for patients achieving complete response (CR) and uncomplete response (X2 = 30.68, P = 0. 000).The CR rate was 56% and 86% for radiotherapy of ≤50 Gy and >50 Gy (X2 =6.11, P=0. 013). The corresponding 5-year relapse-free survival rate was 89% and 84% (X2 =0.36, P=0.551). Of 68 patients receiving initial chemotherapy, the CR rate of those who received ≤2, 3-4 and ≥5 cycles was 0, 20%and 3 3 % , respectively (X2 = 7.65 , P = 0. 022) . For 5 0 patients who received ≥ 3 cycles of initial chemotherapy and 17 patients who received initial radiotherapy of ≥40 Gy, the CR rate was 28% and 88%(χ2= 18. 75, P= 0. 000). In patients with pathological nodular and ulcer type, the CR rates with radiotherapy were higher than with chemotherapy (100% 38%, χ2 = 7.92, P = 0. 005; and 100% 11%,χ2 = 14.40, P = 0. 000). Multivariate analysis showed that stage and recent effect were the independent prognostic factors. Conclusions The initial radiotherapy with 50 Gy is appropriate for early stage nasal NK/T cell lymphomas. Combined chemotherapy could be used for extended stage ⅠE and ⅡE, but the outcome of CHOP regimen is poor.