Chapter 9-2: B-ALL with recurrent genetic abnormalities Flashcards
PH positive ALL more common in:
Adults (25% of the adult, 2–4% of children)
Chromosome abnormality in B-ALL with worst prognosis
t(9;22) BCR-ABL1
Immunophenotype of t(9;22) B – ALL
+ 10, 19, TdT
More frequent myeloid (13, 33)
CD25
CD25 expression in B-ALL higly assd with what genetic abnormality
t(9;22)
t(9;22) may rarely have _______ phenotype
T precursor
BCR-ABL1 in B-ALL usually is ____ kd
p190
50% of adult is p210
Chromosome abnormality most frequently seen in B-ALL in <1yr olds
MLL (KMT2A) rearrangements
MLL rearrangements found by what type of FISH probe
Breakapart
Clinical features of MLL rearranged ALL
WBC >100
CNS positive
In some cases of leukemia with MLL rearrangement, it amy be possible to recognize distinct lymphoblastic and ____ populations. This should be considered _____.
Monoblastic
B/myeloid leukemia
Typical immunophenotype of t(4;11) or MLL rearranged ALL
19+, 10-, 15+, NG2+
abnormality seen in B-ALL with phenotype of 19+, 15+, NG2+, 10-
t(4;11), MLL
most common translocation partner in MLL rearranged B-ALL
AF4 on 4q21
2 other translocation partners with MLL
ENL on 19p13
AF9 on 9p22
MLL-ENL fusions/ t(9;19) also common in
T-ALL
MLL-AF9 t(9;11) mosre common in ___ than B-ALL
myeloid leukemia
MLL leukemias frequently associated with what other abnormality
FLT3 overexpression
B-ALL with very favorable prognosis
t(12;21) ETV6-RUNX1
hyperdiploidy
B-ALL with t(12;21) is ___% of B-ALL in children, ___ in adults, ___ in infants
25% in children
rare in adults
rare in infants
immunophenotype of t(12;21) B-ALL
myeloid antigens (13, 33) common absent 9, 20, 66c
chromosome trisomies with best prognosis
4, 10, 17 together
definitition of hypodiploid B-ALL
greater than 50 chromosomes
hyperdiploid B-ALL common in ___, rare in ____, not seen in ___
common in children
rare in adults
not seen in infants
most commonly increased chromosomes in hyperdiploid B-ALL
21, X, 14, 4
pitfall for hyperdiploid B-ALL
hypodiploid B-ALL with endoreduplication
definition of hypodiploid ALL
less than 46 chromosomes
hypodiploid ALL seen in ____
children adn adults
near-haploid ALL seen in ___
children only
structural abnormalities are uncommon in ___
near-haploid ALL
if discrepancy between karyotype and FISH in regards to chomosome number, suspect___
hypodiploidy
B-ALL with eosinophilia
t(5;14) IL3-IGH
Prognosis of B-ALL with t(5;14)
used to be bad prognosis, but with new chemo, not so bad anymore
B-ALL with cytoplasmic mu heavy chain positive pre-Bcell phenotype
t(1;19) TCF3-PBX1
Immunophenotype of t(1;19) B-ALL
positive cytoplasmic mu heavy chain
strong CD9+
CD34- or limited
