Precursor Neoplasms: T and B-ALL/LBL Flashcards
What is the immunophenotype of
blasts of Precursor B-ALL/LBL, NOS?
- Positive for:
- CD19
- CD10
- PAX5
- CD34
- CD99, HLA-DR
- Nuclear Tdt
How does the Burkitt Lymphoma
IHC panel compare to precursor B-ALL/LBL?
- CD19 +
- CD20 +
- CD10 +
- HLA-DR and CD99 +
- TDT (-)
- surface immunoglobulin (+)
What is the immunophenotype of
precursor T-ALL/LBL?
- CD19 (-)
- CD20 (-)
- CD10 (-)
- HLA-DR (-)
- surface immunoglobulin (-)
- CD7 and TdT (+)
What is the prognosis for patients with B-ALL/LBL
in children and adults?
- Children: CR >95%
- Adults: CR 80%
This is with therapy. Adults have a slightly worse prognosis.
What are the key prognostic variables for
B-ALL/LBL patients?
- Favorable:
- age: 1-9 years old
- WBC: <50,000
- good response to initial treatment
What genetic finding is associated with
a poor prognosis in B-ALL/LBL?
- hypodiploidy (46 chromosomes)
What are general characteristics of
Lymphoblastic lymphoma and lymphoblastic leukemia?
- LBL: lesions involve the tissue and spare the peripheral blood
- ALL: lesions heavily involve the marrow and peripheral blood
When does ALL peak and
what are the characteristics of ALL?
- peaks: at age 3
- most childhood ALL = B-ALL
- 10% are T-ALL
- T-ALL is more common in males and teens
- <15%
- most are LBL 85-90%
What are risk factors for the development of
ALL/LBL?
- Down Syndrome
- Fanconi Anemia
- Li-Fraumeni Syndrome
- Ataxia-Telangiectasia
- Bloom Syndrome
What is the characteristic clinical presentation
of T-LBL?
- anterior mediastinal mass
- may be associated with hypercalcemia
What is the characteristic clinical presentation of
B-LBL?
- involves the lymph nodes, CNS, liver, spleen and testes
- does not involve the mediastinum
Note: both present with fatigue and cytopenis with or without bone pain
What is the characteristic morphology of
T or B-ALL/LBL?
- monotonous proliferation of undifferentiated blasts
- T-LBL may be associated with infiltrating eosinophils
- PAS-positive in block pattern
- negative for MPO
- negative for Sudan black B
What is the most common molecular finding
in B-ALL/LBL that has a poor prognosis?
- t(9;22)
- BCR-ABL
- minor breakpoint 190 kd chimeric protein
- different than the CML breakpoint which is 210
- distinctly unfavorable finding
What are the translocation proteins, morphology, prognosis and age group of
B-ALL/LBL with t(9;22)?
- genetics: BCR/ABL
- age group:
- adults: 25% (p210, p190)
- children: 3% (p190)
- poor prognosis
- usual morphology
What are the IHC findings of
t(9;22) B-ALL/LBL?
- CD19 +
- CD10 +
- Tdt +
- CD34 +
- CD13/33 + (weak)
- CD25 +