Acute lymphoblastic leukemia with Burkitt-like morphologic features and high myeloperoxidase activity.
Expression of a high level of myeloperoxidase (MPO) as a sole myeloid marker in acute leukemias that express typical lymphoblastic markers is unusual. Herein we report 5 cases of MPO+, otherwise typical acute lymphoblastic leukemia (ALL) without the expression of other myeloid markers. In most cases, MPO positivity was detected in more than 20% of blasts by immunologic (flow cytometric) and enzymatic testing. The striking feature of most of these cases is a morphologic picture reminiscent of that seen in Burkitt-like B-cell ALL with basophilic cytoplasm and vacuoles but no expression of surface immunoglobulin. All cases responded to ALL therapy and should be distinguished from myeloid leukemia and from Burkitt leukemia/lymphoma.
Rytting
Michael E
ME
Pediatric Department, M.D. Anderson Cancer Center, University of Texas, 1515 Holcombe Blvd, Box 87, Houston, TX 77030, USA.
Kantarjian
Hagop
H
Albitar
Maher
M
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000032:analysis*; D005434:Flow Cytometry; D006801:Humans; D008875:Middle Aged; D009195:Peroxidase / Q000378:metabolism*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology*; D016896:Treatment Outcome
D014408:Biomarkers, Tumor; D009195:Peroxidase