Table of Contents
Definition / general | Treatment | Microscopic (histologic) description | Microscopic (histologic) images | Cytology images | Positive stains | Flow cytometry images | Molecular / cytogenetics description | Molecular / cytogenetics imagesCite this page: Mihova D. t(9;22)(q34;q11); BCR::ABL1. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/leukemiapreBt922.html. Accessed December 2nd, 2024.
Definition / general
- ALL with BCR-ABL1 fusion transcript (Philadelphia chromosome)
- 30% of adults with ALL, 4% of children but 80% of infants
- Excluding infants, older age and higher WBC at presentation than other B ALL
- May have more organomegaly or CNS involvement than other B ALL
- Poor prognosis
Treatment
- Tyrosine kinase inhibitors (Imatinib) cause some complete responses (Cancer 2007;110:1178), but change in overall survival is minimal (Cancer 2007;109:2068, Hematology Am Soc Hematol Educ Program 2007:435)
Microscopic (histologic) description
- No defining morphology, but large blasts with prominent nucleoli and cytoplasmic granules are more common than other B ALL
Positive stains
- Myeloid antigens in 71% (Am J Clin Pathol 1999;111:467)
Flow cytometry images
Molecular / cytogenetics description
- Translocation involves abl on #9q34 (tyrosine kinase) and bcr on #22q11 (breakpoint cluster region)
- Most childhood cases associated with p190 kd BCR-ABL1 fusion protein
- In 50% of adults, has p210 kd fusion protein that is present in CML, the rest is p190 kd; no definitive clinical difference