title: Clinical outcomes and prognostic factors in patients with breast diffuse large B cell lymphoma; Consortium for Improving Survival of Lymphoma (CISL) study.
abstract: BACKGROUND
  The breast is a rare extranodal site of non-Hodgkin lymphoma, and primary breast lymphoma (PBL) has been arbitrarily defined as disease localized to one or both breasts with or without regional lymph nodes involvement. The aim of this study was to evaluate the clinical outcomes in patients with diffuse large B cell lymphoma (DLBCL) and breast involvement, and to find the criteria of PBL reflecting the outcome and prognosis.
  
  
  METHODS
  We retrospectively analyzed data from 68 patients, newly diagnosed with DLBCL and breast involvement at 16 Korean institutions between January 1994 and June 2009.
  
  
  RESULTS
  Median age at diagnosis was 48 years (range, 20-83 years). Forty-three (63.2%) patients were PBL according to previous arbitrary criteria, sixteen (23.5%) patients were high-intermediate to high risk of international prognostic index. The patients with one extranodal disease in the breast (OED) with or without nodal disease were 49 (72.1%), and those with multiple extranodal disease (MED) were 19 (27.9%). During median follow-up of 41.5 months (range, 2.4-186.0 months), estimated 5-year progression-free survival (PFS) was 53.7 +/- 7.6%, and overall survival (OS) was 60.3 +/- 7.2%. The 5-year PFS and OS was significantly higher for patients with the OED group than those with the MED group (5-year PFS, 64.9 +/- 8.9% vs. 27.5 +/- 11.4%, p = 0.001; 5-year OS, 74.3 +/- 7.6% vs. 24.5 +/- 13.0%, p < 0.001). In multivariate analysis, MED (hazard ratio [HR], 3.61; 95% confidence interval [CI], 1.07-12.2) and fewer than four cycles of systemic chemotherapy with or without local treatments (HR, 4.47; 95% CI, 1.54-12.96) were independent prognostic factors for worse OS. Twenty-five (36.8%) patients experienced progression, and the cumulative incidence of progression in multiple extranodal sites or other than breasts and central nervous system was significantly different between the OED group and the MED group (5-year cumulative incidence, 9.7 +/- 5.4% vs. 49.0 +/- 15.1%, p = 0.001).
  
  
  CONCLUSIONS
  Our results show that the patients included in OED group, reflecting different treatment outcome, prognosis and pattern of progression, should be considered as PBL in the future trial. Further studies are warranted to validate our suggested criteria.
authors.affiliation: Department of Internal Medicine, Chonbuk National University Medical School, Jeonju, Korea.
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Yhim
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kang
authors.forename: Yoon Hee
authors.initials: YH
authors.lastname: Choi
authors.forename: Seok Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Won Seog
authors.initials: WS
authors.lastname: Kim
authors.forename: Yee Soo
authors.initials: YS
authors.lastname: Chae
authors.forename: Jin Seok
authors.initials: JS
authors.lastname: Kim
authors.forename: Chul Won
authors.initials: CW
authors.lastname: Choi
authors.forename: Sung Yong
authors.initials: SY
authors.lastname: Oh
authors.forename: Hyeon Seok
authors.initials: HS
authors.lastname: Eom
authors.forename: Jeong-A
authors.initials: JA
authors.lastname: Kim
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Jong-Ho
authors.initials: JH
authors.lastname: Won
authors.forename: Hyeok
authors.initials: H
authors.lastname: Shim
authors.forename: Je-Jung
authors.initials: JJ
authors.lastname: Lee
authors.forename: Hwa Jung
authors.initials: HJ
authors.lastname: Sung
authors.forename: Hyo Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Dae Ho
authors.initials: DH
authors.lastname: Lee
authors.forename: Cheolwon
authors.initials: C
authors.lastname: Suh
authors.forename: Jae-Yong
authors.initials: JY
authors.lastname: Kwak
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000145:classification / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D016009:Chi-Square Distribution; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016403:Lymphoma, Large B-Cell, Diffuse / Q000145:classification / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D008875:Middle Aged; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D056910:Republic of Korea; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult