title: The impact of the World Health Organization classification and clonality assessment of posttransplant lymphoproliferative disorders on disease management.
abstract: BACKGROUND
  The World Health Organization classification of posttransplant lymphoproliferative disorders divides them into 4 main categories.
  
  
  OBJECTIVE
  To classify cases of posttransplant lymphoproliferative disorders diagnosed in our institution according to the World Health Organization scheme and correlate the classification and clonality with clinical data.
  
  
  METHODS
  Cases of posttransplant lymphoproliferative disorders were reviewed. They were classified according to the World Health Organization scheme. Clonality was determined by flow cytometry and/or polymerase chain reaction. Patients' charts were reviewed.
  
  
  RESULTS
  Thirty-one cases were identified. Median age was 33 years. There were 19 cases of kidney, 8 cases of liver, and 4 cases of bone marrow transplant. Immunosuppression consisted of cyclosporin A and prednisone (N = 24) or FK506 and prednisone (N = 7). Twenty cases (63%) were World Health Organization type 3, 7 cases (23%) type 2, 3 cases (6.4%) type 1, and 1 case type 4 posttransplant lymphoproliferative disorder. Ten patients received chemotherapy, 20 patients had reduction of immunosuppression, and 1 had no treatment. Follow-up was available on 25 patients. Seven (43.75%) of 16 with type 3 lesions with available follow-up died of their disease. Five of these patients received reduction of immunosuppression alone. Only 2 of 9 patients with type 3 disease who received chemotherapy died of disease. Two patients with type 2 disease died of unrelated causes. One patient is alive with disease; the remaining patients with types 1 and 2 disease are alive with no disease.
  
  
  CONCLUSIONS
  The World Health Organization classification of posttransplant lymphoproliferative disorders is valuable in the identification of subtypes. It helps identify early lesions (1 and 2) requiring reduction of immunosuppression and type 3 disease, which requires chemotherapy from the outset.
authors.affiliation: King Faisal Specialist Hospital and Research Center, Department of Pathology, Riyadh, Saudi Arabia 11211. wmourad@hotmail.com
authors.forename: Walid A
authors.initials: WA
authors.lastname: Mourad
authors.forename: Asma
authors.initials: A
authors.lastname: Tulabah
authors.forename: Adher
authors.initials: A
authors.lastname: Al Sayed
authors.forename: Madras
authors.initials: M
authors.lastname: Raja
authors.forename: Yasser
authors.initials: Y
authors.lastname: Khafaga
authors.forename: Hazem
authors.initials: H
authors.lastname: El Gamal
authors.forename: Mohamed
authors.initials: M
authors.lastname: Al Shabanah
authors.forename: Khaled
authors.initials: K
authors.lastname: Al Meshari
authors.forename: Khaled
authors.initials: K
authors.lastname: Al Shaibani
authors.forename: Adnan
authors.initials: A
authors.lastname: Ezzat
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016026:Bone Marrow Transplantation / Q000009:adverse effects*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry; D015321:Gene Rearrangement; D019672:Genes, T-Cell Receptor; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007223:Infant; D008232:Lymphoproliferative Disorders / Q000145:classification* / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D016377:Organ Transplantation / Q000009:adverse effects*; D010641:Phenotype; D016896:Treatment Outcome; D014944:World Health Organization
chemical_list: D007143:Immunoglobulin Heavy Chains