| Objective To evaluate the prognosis and determine the failure pattern after radiotherapy for nomogram-revised risk index(NRI)-defined low-risk early-stage patients with extranodal NK/T-cell lymphoma,nasal-type(ENKTCL).Methods A total of 557 patients with NRI-defined low-risk early-stage ENKTCL who received radiotherapy with or without chemotherapy from the China Lymphoma Collaborative Group(CLCG)were retrospectively reviewed.427 patients(76.7%)received combined modality therapy,whereas 130 patients(23.3%)received radiotherapy alone.Survivals were calculated by Kaplan-Meier method and compared with log-rank test.Overall survival(OS)was compared with age-and sex-matched general Chinese population using expected survival and standardized mortality ratio(SMR).Cox stepwise regression model was used for multivariate analysis.Results The 5-year OS and progression-free survival(PFS)were 87.2%and 77.2%,respectively.The SMR of the patients was 4.99(P<0.001)compared with country-matched general population.The SMR was 3.59(P<0.001)at 1 year after treatment,whereas it was 1.5(P=0.146)at 4 years after treatment without significant difference between ENKTCL group and country-matched general population.Compared with radiotherapy alone,combined modality therapy did not result in significantly superior OS(87.0%vs 87.4%,P=0.961)or PFS(76.1%vs 80.7%,P=0.129).Local failure(11.5%)and distant failure(10.8%)were the main failure modes,while regional failure was rare(2.9%).The 5-year locoregional control rate(LRC)was 87.2%for the whole group,with 89.5%for≥50 Gy versus 73.7%for<50 Gy(P<0.001).Cox multivariate analysis showed the primary site(P=0.028),radiation dose(P=0.001)and tumor response at first-line treatment(P<0.001)were the prognostic factors of LRC.Conclusion Radiotherapy achieved a favorable prognosis in patients with NRI low-risk early-stage ENKTCL.The incidence of either locoregional or distant failure was low.Radiation dose still was an important prognostic factor for LRC. |
PDF Full Text Request