title: Tumor necrosis at FDG-PET is an independent predictor of outcome in diffuse large B-cell lymphoma.
abstract: OBJECTIVE
  To determine the prognostic performance of tumor necrosis at FDG-PET in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) who are treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy.
  
  
  METHODS
  108 patients with newly diagnosed DLBCL who underwent FDG-PET before R-CHOP therapy were retrospectively included. Lymphomatous sites at FDG-PET were assessed for the presence of a photopenic area, in keeping with tumor necrosis. Univariate and multivariate Cox regression analyses were performed to determine the associations of tumor necrosis and National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) with progression-free survival (PFS) and overall survival (OS).
  
  
  RESULTS
  On univariate Cox regression analysis, both tumor necrosis and higher NCCN-IPI risk groups were significantly associated with PFS (P=0.024 and P<0.001, respectively) and OS (P=0.034 and P<0.001, respectively). On multivariate Cox regression analysis, both tumor necrosis and the NCCN-IPI were independent significant predictors for PFS (P=0.007, hazard ratio: 2.723 [95% confidence interval: 1.324-5.597] and P<0.001, hazard ratio: 2.952 [95% confidence interval: 1.876-4.646], respectively) and OS (P=0.009, hazard ratio: 2.794 [95% confidence interval: 1.305-5.985] and P<0.001, hazard ratio: 2.813 [95% confidence interval: 1.724-4.587], respectively).
  
  
  CONCLUSIONS
  Tumor necrosis at FDG-PET is an NCCN-IPI-independent predictor of outcome in DLBCL.
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: h.j.a.adams@gmail.com.
authors.forename: Hugo J A
authors.initials: HJA
authors.lastname: Adams
authors.affiliation: Department of Nuclear Medicine, Meander Medical Center, Amersfoort, The Netherlands.
authors.forename: John M H
authors.initials: JMH
authors.lastname: de Klerk
authors.affiliation: Department of Hematology, Meander Medical Center, Amersfoort, The Netherlands.
authors.forename: Rob
authors.initials: R
authors.lastname: Fijnheer
authors.affiliation: Department of Radiology, Meander Medical Center, Amersfoort, The Netherlands.
authors.forename: Ben G F
authors.initials: BGF
authors.lastname: Heggelman
authors.affiliation: Department of Pathology, Meander Medical Center, Amersfoort, The Netherlands.
authors.forename: Stefan V
authors.initials: SV
authors.lastname: Dubois
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Rutger A J
authors.initials: RAJ
authors.lastname: Nievelstein
authors.affiliation: Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Kwee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Diffuse large B-cell lymphoma; FDG-PET; Necrosis; Prognosis; R-CHOP