ALL Flashcards
Typical laboratory features of ALL at diagnosis include:
- Leukocytosis (up to 100,000/mm3) in most cases
- Normocytic normochromic anemia (Hb < 10g/dl)
- Thrombocytopenia (platelet count < 50,000/mm3)
True or false? Irrespective of the leukocyte count, Romanowsky–stained blood smears nearly always reveal some lymphoblasts (usually > 30%)
True
What’s characteristic of aleukemic ALL when viewing peripheral blood?
No lymphoblasts are seen
How do you detect meningeal involvement by lymphoblasts?
Prepare a Romanowsky stained preparation of CSF
In ALL, the BM is often found to be _____ with almost complete replacement of normal —— by ——
Hypercellular, hematopoietic cells, leukemic lymphoblasts
In ___ BM is often found to be hypercellular with almost complete replacement of normal hematopoietic cells by leukemic lymphoblasts
Acute lymphoblastic leukemia
FAB classification system is based on the ___ appearance of the leukemic blasts by using ___ ___
Morphologic, light microscopy
Describe ALL L1 subtype morphology
regarding size, nucleus, chromatin, cytoplasm and nucleolus
Size: small round blasts that are uniform in size and shape but up to 20% variation is allowed
Cytoplasm: scanty and bluish
Nucleus: regular round shape, but may have a cleft or an indentation.
This indentation is called Rieder’s deformity
Chromatin: is dense and homogenous (we don’t see thick and thin areas)
Nucleoli: cannot be seen (indistinct)
True or false: In L1, the diagnosis is established with certainty without cytochemical reactions.
True
Describe L2 blast morphology
- The cell population is extremely heterogeneous and the blasts here are extremely variable in size, predominantly large
- The volume of cytoplasm is variable, but often abundant with variable basophilia (blue to gray).
- The nuclear shape is irregular with indentation and folding.
- The nuclear chromatin is heterogeneous and variable, it can be very delicate or coarse.
- One or two very distinct nucleoli are always very sharp.
- Some lymphoblasts show what we call a hand-mirror deformity
Describe L3 blast morphology
- The cells are large and homogeneous, uniform in size
- The nucleus is large, usually rounded or oval without indentation or clefting.
- The chromatin is dense but finely stippled
- One or more prominent nucleoli are visible in most cells. This is the only lymphoid
tumor which can show up to 5 nucleoli (1-5). - The cells show an abundant cytoplasm which is intensely basophilic (because it is
extremely rich in RNA) and which completely surrounds the nucleus. In addition, the cytoplasm shows intense vacuolization which is characteristic of the Burkitt cell.
In fact, vacuoles may be seen all over the cell (Blasts are rich in neutral fats which are alcohol soluble leaving many vacuoles)
True or false: because of the age incidence and morphological features of L2, differentiation from myeloblastic leukemia (M0/M1) can at times be quite difficult. Therefore cytochemistry is very important in these instances for confirmation.
True
T/F: L2 is usually the adult type of lymphoblastic leukemia or it is the type that occurs also below 2 years of age. It constitutes ~ 70% of all lymphoblastic leukemias and its outcome is far less happy than L1
False —> 30%
T/F: A low mitotic index (approximately 5%) is characteristic of L3
False —> high
T/F: HLA-DR, CD19, CD10 and CD20 antigens are all B-cell specific.
False, they all are except for HLA-DR
T/F: the different types of leukemias represent development arrested at different stages, as reflected in the antigens these leukemias display
True
T/F: Depending on where in the pathway the cell deviates into uncontrolled growth, the ALL clone will have a characteristic pattern of antigens/markers as determined by ELISA
False: flow cytometry
Expression of CD13 and CD33 suggests which type of leukemia?
Myeloid
Expression of CD14 will distinguish leukemias of ____ origin?
Monocytic
T/F: T-ALL cases are identified on the basis of CD2, CD5 and CD7
True
Early pre-B ALL or pre pre- B ALL make up 70% cases of ALL
True
T/F: L3 morphology cells have cell surface immunoglobulin expressed on their surface (usually SIgM)
True
T/F: Various subtypes of acute leukemia are absolute, no hybrid cases occur.
False —> there can be hybrid cases
Which immunologic type of ALL involves male predominance, a high WBC and a mediastinal mass and CNS involvement?
T-ALL
Which immunologic type of ALL has positivity for HLA-DR, CD19, CD20, CD22, variability in presence of CD10 and SIgM?
Hint: TdT and CD34 negative
B-ALL
Which immunologic type of ALL has L3 morphology? What are the cells called in this case?
B-ALL
Burkitt cells
Which immunologic type of ALL is positive for HLA-DR, TdT, CD19, CD20 and variability in CD10? What is it characterized by?
Pre-B ALL
Presence of heavy chains
Which immunologic type of ALL comprises 70% of cases?
Pre-pre-B ALL
Which immunologic type of ALL is positive for HLA-DR, TdT, CD10 and CD19?
Pre-pre-B ALL
Which immunologic type of ALL has mainly L2 cells?
Pro-B ALL
Which immunologic type of ALL is positive for HLA-DR, TdT, CD19 and CD34?
Pro-B ALL
T/F: Most patients with ALL have demonstrable karyotypic BM abnormalities
True
