Expression of CD66c and CD25 in acute lymphoblastic leukemia as a predictor of the presence of BCR/ABL rearrangement

• Published in: Hematology/oncology and stem cell therapy 2008, Vol.1 (1), p.34-37
• Main Authors: Owaidah, Tarek M, Rawas, Faisal I, Al khayatt, Mazen F, Elkum, Nasser B
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Antigens, CD - biosynthesis; Biomarkers, Tumor - analysis; Cell Adhesion Molecules - biosynthesis; Child; Child, Preschool; Female; Fusion Proteins, bcr-abl - genetics; Fusion Proteins, bcr-abl - metabolism; GPI-Linked Proteins; Hematology, Oncology and Palliative Medicine; Humans; Immunophenotyping; In Situ Hybridization, Fluorescence; Interleukin-2 Receptor alpha Subunit - biosynthesis; Male; Middle Aged; Precursor Cell Lymphoblastic Leukemia-Lymphoma - genetics; Precursor Cell Lymphoblastic Leukemia-Lymphoma - metabolism; Reverse Transcriptase Polymerase Chain Reaction; Translocation, Genetic; Young Adult
• ISSN: 1658-3876
• DOI: 10.1016/S1658-3876(08)50058-6

BACKGROUND Expression of myeloid or T cell lymphoid in precursor B cell acute lymphoblastic leukemia (pre-B cell ALL), which is referred to as aberrant expression, is quite a common phenomenon. CD66c is a myeloid marker which has aberrant expression in pre-B cell ALL, with strong correlation with non-random genetic changes (BCR/ABL rearrangement). Another leukemia associated marker (CD25) is frequently expressed in pre-B cell ALL. The frequency of CD25–expressing lymphoblasts has been found to be significantly higher in BCR/ABL-positive vs. BCR/ABL-negative patients. METHODS In a cohort of 103 patients diagnosed with pre-B cell ALL or biphenotypic leukemia and studied for expression of CD66c and CD25 at presentation, we evaluated the frequency of expression of either or both in BCR/ABL positive cases. RESULTS Surface CD66c was expressed by 70 cases (68%) and CD25 was expressed by 33 cases (32%) while both were expressed together on 29 cases (28%). BCR/ABL was positive in 18/103 patients. All BCR/ABL positive cases were positive for surface CD66c and CD25. CONCLUSION Positivity for both leukemia-associated antigens CD66c and CD25 in combination can predict the presence of BCR/ABL rearrangement in pre-B cell ALL. While this finding does not replace the detection of BCR/ABL abnormality by cytogenetic or molecular techniques, it does provide an early and handy tool for prediction and management of high-risk cases of pre-B cell ALL, especially in centers with limited laboratory facilities.