The World Health Organization classification of posttransplant lymphoproliferative disorders divides them into 4 main categories.
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.
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.
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.
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.