Clinical usefulness of immunocytochemical detection of myeloperoxidase in undifferentiated and biphenotypic acute leukemias.
BACKGROUND
The use of monoclonal antibodies has been recently proposed as a more sensitive technique than conventional cytochemistry in recognizing myeloperoxidase (MPO) in leukemic cells.


METHODS
In order to verify the diagnostic relevance of such an approach, the immunocytochemical detection of MPO by means of the APAAP technique and a monoclonal antibody directed against an antigenic determinant of MPO (MPO7) was performed in 10 patients with undifferentiated or biphenotypic (myeloid and lymphoid) acute leukemia. All the cases were negative for conventional cytochemical staining of MPO.


RESULTS
Positive cells (15 to 65%) were found in three patients. Some clinical data and biomolecular studies of T-cell receptor and immunoglobulin genes, available in five patients, indirectly confirmed these findings.


CONCLUSIONS
Although some technical and biological aspects remain to be better characterized, immunocytochemical methods which utilize monoclonal antibodies against MPO may represent a simple and reliable tool for improving the diagnostic capacity to identify undifferentiated myeloid blasts in difficult cases of acute leukemia.
Musto
P
P
Divisione di Ematologia, Istituto di Ricovero e Cura a Carattere Scientifico Casa Sollievo della Sofferenza, Rotondo (FG), Italy.
Cascavilla
N
N
Melillo
L
L
Matera
R
R
Carotenuto
M
M
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology*; D015703:Antigens, CD / Q000032:analysis; D000951:Antigens, Neoplasm / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis*; D001853:Bone Marrow / Q000473:pathology; D005260:Female; D015322:Gene Rearrangement, B-Lymphocyte; D015329:Gene Rearrangement, T-Lymphocyte; D006801:Humans; D007938:Leukemia / Q000145:classification / Q000201:enzymology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis; D014411:Neoplastic Stem Cells / Q000201:enzymology* / Q000276:immunology; D009195:Peroxidase / Q000032:analysis* / Q000276:immunology
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D009195:Peroxidase