title: Treatment outcomes of and prognostic factors for definitive radiotherapy with and without chemotherapy for Stage I/II nasal extranodal NK/T-cell lymphoma.
abstract: Treatment strategies for nasal extranodal NK/T-cell lymphoma (ENKTL), including sequential chemotherapy followed by radiotherapy (SCRT), concurrent chemoradiotherapy (CCRT), or radiotherapy alone (RT), remain varied. The purpose of this study was to assess the treatment outcome, the toxicity, and the potential prognostic factors for patients with early-stage nasal ENKTL treated using definitive RT (minimum of 50 Gy) with or without chemotherapy. From 1998 to 2014, 37 patients were included in the study. Eight patients were treated with RT alone, 1 with CCRT, and 28 with SCRT. Local regional control (LRC), progression-free survival (PFS), and overall survival (OS) were calculated using the Kaplan-Meier method. RT resulted in an overall response rate of 91.2%, with a complete response rate of 78.4%. After a median follow-up time of 36.8 months, the 3-year LRC, PFS and OS were 87.4%, 64.0% and 76.3%, respectively. Acute severe toxicity (Grade 3) of mucositis was observed in 6 (16.2%) of the 37 patients. In univariate analyses, extensive disease (Stage I/II with local invasiveness) and the presence of B symptoms were significantly associated with a poor PFS, whereas extensive disease was significantly associated with a poor OS. Multivariate analysis identified the presence of extensive disease as an independent predictor of PFS (P < 0.001) and OS (P = 0.015). High-dose RT with or without chemotherapy reported promising locoregional control and a favorable outcome for patients with early-stage nasal ENKTL without local invasiveness. Further investigation of new treatment strategies for patients with local invasiveness is warranted.
authors.affiliation: Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Claire Wen-Chi
authors.initials: CW
authors.lastname: Yang
authors.affiliation: Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chun-Wei
authors.initials: CW
authors.lastname: Wang
authors.affiliation: Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Ruey-Long
authors.initials: RL
authors.lastname: Hong
authors.affiliation: Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chiao-Ling
authors.initials: CL
authors.lastname: Tsai
authors.affiliation: Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Ming
authors.initials: M
authors.lastname: Yao
authors.affiliation: Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Jih-Luh
authors.initials: JL
authors.lastname: Tang
authors.affiliation: Department of Pathology, National Taiwan University Hospital and National Taiwan University Cancer Center, Taipei, Taiwan.
authors.forename: Chung-Wu
authors.initials: CW
authors.lastname: Lin
authors.affiliation: Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan.|Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan.|Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Ann-Lii
authors.initials: AL
authors.lastname: Cheng
authors.affiliation: Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan shkuo101@ntu.edu.tw.|Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan.|Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan.|Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Sung-Hsin
authors.initials: SH
authors.lastname: Kuo
mesh_terms: D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D054391:Lymphoma, Extranodal NK-T-Cell / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D016896:Treatment Outcome
keywords: chemotherapy; nasal NK/T-cell lymphoma; prognosis; radiotherapy