title: Posttransplantation lymphoproliferative disorder in children: manifestations in hematopoietic cell recipients in comparison with liver recipients.
abstract: OBJECTIVE
  To compare the clinical and imaging features of posttransplantation lymphoproliferative disorder (PTLD) in pediatric patients who underwent hematopoietic cell transplantation with those in pediatric patients who underwent liver transplantation.
  
  
  METHODS
  This study was approved by the institutional review board, and the requirement to obtain informed consent was waived. The authors retrospectively reviewed the medical records and images of 552 hematopoietic cell transplant recipients and 195 liver transplant recipients. PTLD was histopathologically confirmed in 17 of the patients who underwent hematopoietic cell transplantation and 27 of the patients who underwent liver transplantation. The overall frequency, clinical course, histopathologic type, and imaging findings of PTLD were compared between the two patient groups by using the Fisher exact test.
  
  
  RESULTS
  The overall frequency of PTLD was 3% (17 of 552 patients) after hematopoietic cell transplantation (12% [nine of 75 patients] after umbilical cord blood transplantation) and 14% (27 of 194 patients) after liver transplantation. PTLD occurred within 6 months of transplantation in 14 of the 17 hematopoietic cell recipients (82%) and 11 of the 27 liver recipients (41%) (P = .012). Histopathologic examination revealed monomorphic disease in 11 of the 17 hematopoietic cell recipients (65%) and eight of the 27 liver recipients (30%) (P = .031). The abdomen was the most common site of involvement in both groups. Extraabdominal PTLD developed in 12 of the 17 hematopoietic cell recipients (71%) and five of the 27 liver recipients (19%) (P = .002). Although 15 of the 17 patients with hematopoietic cell transplantation-related PTLD (88%) exhibited responses after treatment, the overall mortality rate was 35% (six of 17 patients). All 27 patients with PTLD after liver transplantation improved after treatment and remain alive.
  
  
  CONCLUSIONS
  PTLD after umbilical cord blood transplantation occurred as frequently as liver transplantation-related PTLD. Compared with liver transplantation-related PTLD, PTLD after hematopoietic cell transplantation is characterized by an earlier onset, a higher proportion of malignant monomorphic disease, and a worse outcome.
authors.affiliation: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, Korea.
authors.forename: Tae Yeon
authors.initials: TY
authors.lastname: Jeon
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Kim
authors.forename: Hong
authors.initials: H
authors.lastname: Eo
authors.forename: So-Young
authors.initials: SY
authors.lastname: Yoo
authors.forename: Keon Hee
authors.initials: KH
authors.lastname: Yoo
authors.forename: Suk-Koo
authors.initials: SK
authors.lastname: Lee
authors.forename: Gye Yeon
authors.initials: GY
authors.lastname: Lim
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Cheon
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media; D005260:Female; D005312:Fetal Blood / Q000637:transplantation; D019786:Gadolinium DTPA; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects* / Q000401:mortality; D006801:Humans; D007479:Iopamidol / Q000031:analogs & derivatives; D016031:Liver Transplantation / Q000009:adverse effects* / Q000401:mortality; D008232:Lymphoproliferative Disorders / Q000175:diagnosis* / Q000209:etiology* / Q000401:mortality; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol; D019786:Gadolinium DTPA