Acute promyelocytic leukemia at time of relapse commonly demonstrates cytogenetic evidence of clonal evolution and variability in blast immunophenotypic features.
Despite the success of the current therapy for patients with acute promyelocytic leukemia (APL), relapse occurs in up to 30% of patients. The characteristics of relapsed APL are not well described. We evaluated a group of APL cases at relapse and compared the clinicopathologic, immunophenotypic, molecular, and cytogenetic findings with those at initial diagnosis. From a group of 207 patients with APL, in 38 patients morphologic evidence of relapse developed. In 30 patients relapse was isolated to bone marrow, and 8 had extramedullary disease. Blasts were morphologically stable in 37 patients. Changes in the immunophenotypic profile were common, the most frequent being gain of CD34, HLA-DR, or CD33 and attenuation or loss of CD13. Cytogenetic changes were common at relapse. The size of the PML-RARalpha fusion transcript was invariable. We conclude that changes in the immunophenotype and cytogenetic evidence of clonal evolution are common in APL at the time of relapse.
Dept. of Hematopathology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030, USA.
Nikolay D
ND
Dimov
L Jeffrey
LJ
Medeiros
Farhad
F
Ravandi
Carlos E
CE
Bueso-Ramos
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003582:Cytogenetics; D005260:Female; D005434:Flow Cytometry; D015973:Gene Expression Regulation, Leukemic / Q000235:genetics / Q000276:immunology; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics* / Q000276:immunology*; D012008:Recurrence; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction
D009363:Neoplasm Proteins