title: A new prognostic model using absolute lymphocyte count in patients with primary central nervous system lymphoma.
abstract: OBJECTIVE
  Primary central nervous system lymphoma (PCNSL) is an aggressive and rare extranodal non-Hodgkin lymphoma (NHL). Absolute lymphocyte count (ALC) has been suggested to have a prognostic value in several subtypes of NHL. We evaluated the prognostic significance of clinical factors, including ALC, in patients with PCNSL to develop a new prognostic model.
  
  
  METHODS
  We analysed prognostic factors, including ALC, at diagnosis in 81 PCNSL patients receiving high-dose methotrexate-based therapy.
  
  
  RESULTS
  The median ALC at diagnosis was 1210 × 10(6)/L (range, 210-3610), with lymphopenia (≤ 875 × 10(6)/L) being detected in 27 (33.3%) patients. In the multivariate analysis, Eastern Cooperative Oncology Group performance status (ECOG PS) >1 (hazard ratio [HR] 3.18, P=0.003), age >50 years (HR 4.23, P=0.012), and lymphopenia at diagnosis (HR 2.83, P=0.008) remained independent prognostic factors for low overall survival (OS). Lymphopenia was also a significant prognostic factor for progression-free survival (HR 3.17, P=0.001). By means of a new three-factor prognostic model using ECOG PS >1, age >50 years, and presence of lymphopenia, with 1 point assigned to each factor, we successfully classified the patients into three risk groups: low (0 and 1), intermediate (2), and high (3). The 5-year OS rates of the patients in the low-, intermediate-, and high-risk groups were 74.3%, 21.7%, and 12.5%, respectively (P<0.001).
  
  
  CONCLUSIONS
  Low ALC is a useful indicator of poor prognosis in patients with PCNSL. The proposed three-factor model should be validated in large-scale studies.
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Jang
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Yu Ri
authors.initials: YR
authors.lastname: Kim
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Soo-Jeong
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Hyunsoo
authors.initials: H
authors.lastname: Cho
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Haerim
authors.initials: H
authors.lastname: Chung
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Jung Yeon
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Hyunsung
authors.initials: H
authors.lastname: Park
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Yundeok
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: June-Won
authors.initials: JW
authors.lastname: Cheong
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
authors.forename: Yoo Hong
authors.initials: YH
authors.lastname: Min
authors.affiliation: Division of Hematology, Department of Internal Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea. Electronic address: hemakim@yuhs.ac.
authors.forename: Jin Seok
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002066:Busulfan / Q000008:administration & dosage; D016543:Central Nervous System Neoplasms / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D003131:Combined Modality Therapy; D003907:Dexamethasone / Q000008:administration & dosage; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D018655:Lymphocyte Count / Q000379:methods; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D008231:Lymphopenia / Q000209:etiology / Q000401:mortality*; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage; D008875:Middle Aged; D011379:Prognosis; D033581:Stem Cell Transplantation; D013852:Thiotepa / Q000008:administration & dosage; D014182:Transplantation, Autologous; D014750:Vincristine / Q000008:administration & dosage
chemical_list: D014750:Vincristine; D003907:Dexamethasone; D013852:Thiotepa; D002066:Busulfan; D008727:Methotrexate
keywords: Lymphopenia; Primary central nervous system lymphoma; Prognosis