Peripheral Blood, Bone Marrow, and Tissue Morphology: Neoplastic Hematology

1
Peripheral Blood, Bone Marrow, and Tissue
Morphology Neoplastic Hematology

• Charles Timmons, MD, PhD
• UT Southwestern Medical Center at Dallas
• Dallas, Texas

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3
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Hx 16 yo boy with pallor and bruising. Blood
smear shows anemia, thrombocytopenia,
leukocytosis (100,000/mm3, 90 immature cells).
Flow cytometry on blood shows cells are TdT,
CD10, CD3, CD7, CD4, and CD8.
Interpretation A. AML B. B-cell
ALL C. T-cell ALL D. Hematogone
hyperplasia E. Neuroblastoma
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1
Hx 16 yo boy with pallor and bruising. Blood
smear shows anemia, thrombocytopenia,
leukocytosis (100,000/mm3, 90 immature cells).
Flow cytometry on blood shows cells are TdT,
CD10, CD3, CD7, CD4, and CD8.
Interpretation A. AML B. B-cell
ALL C. T-cell ALL D. Hematogone
hyperplasia E. Neuroblastoma
Comment The cells are T lymphoblasts by
morphology and flow cytometry. Hematogones are
rarely seen in peripheral blood. High white count
and large and small blasts favor T-cell ALL.
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2
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2
Hx 5 yo boy with bruising and cervical
lymph-adenopathy. Blood smear shows pancytopenia
and 20 abnormal cells (pictured). Flow
cytometry on marrow shows 90 of cells are TdT,
CD10, CD3 and CD7. Interpretation A. AML
B. B-cell ALL C. T-cell ALL D. Hematogone
hyperplasia E. Neuroblastoma
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2
Hx 5 yo boy with bruising and cervical
lymph-adenopathy. Blood smear shows pancytopenia
and 20 abnormal cells (pictured). Flow
cytometry on marrow shows 90 of cells are TdT,
CD10, CD3 and CD7. Interpretation A. AML
B. B-cell ALL C. T-cell ALL D. Hematogone
hyperplasia E. Neuroblastoma
Comment The cells are immunophenotypically
precursor T lymphoblasts. Morphologically they
correspond to the old L2 designation from the FAB
classification system.
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3
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3
Hx 6 yo boy with bone pain. Blood smear shows
pancytopenia, and 5 circulating immature cells
(pictured). Flow cytometry on marrow shows 80
cells are TdT, CD10 and CD19.
Interpretation A. AML B. B-cell
ALL C. T-cell ALL D. Hematogone
hyperplasia E. Neuroblastoma
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3
Hx 6 yo boy with bone pain. Blood smear shows
pancytopenia but no blasts. Flow cytometry on
marrow shows 95 cells are TdT, CD10 and CD19.
Interpretation A. AML B. B-cell
ALL C. T-cell ALL D. Hematogone
hyperplasia E. Neuroblastoma
Comment This is a blast by morphology and is B
phenotype by flow cytometry. Hematogones should
show more of a spectrum of maturation and are
unlikely to completely replace the normal marrow
elements. Solid tumor cells tend to clump rather
than cluster.
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4
Hx 15 yo boy with respiratory distress.
Radiology shows cervical and mediastinal
lymphadenopathy, which is biopsied. Flow
cytometry shows a proliferation of cells that are
TdT, CD10, CD3, CD7, CD4 and CD8.
Interpretation A. Myeloid sarcoma B. B
lymphoblastic lymphoma C. T lymphoblastic
lymphoma D. Hodgkin lymphoma E. Reactive
process
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4
Hx 15 yo boy with respiratory distress.
Radiology shows cervical and mediastinal
lymphadenopathy, which is biopsied. Flow
cytometry shows a proliferation of cells that are
TdT, CD10, CD3, CD7, CD4 and CD8.
Interpretation A. Myeloid sarcoma B. B
lymphoblastic lymphoma C. T lymphoblastic
lymphoma D. Hodgkin lymphoma E. Reactive
process
Comment By morphology and flow cytometry, the
immature cells are precursor T lymphoblasts. An
extramedullary mass of lymphoblasts is called
lymphoblastic lymphoma, although it is part of a
biologic continuum referred to as
leukemia/lymphoma.
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5
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5
Hx 16 yo boy with respiratory distress.
Radiology shows a mediastinal mass and a pleural
effusion, which is tapped. Flow cytometry shows
90 of effusion cells are TdT, CD10, CD3,
CD7, CD4 and CD8. Interpretation A. Myeloid
sarcoma B. B lymphoblastic lymphoma C. T
lymphoblastic lymphoma D. Hodgkin
lymphoma E. Reactive process
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5
Hx 16 yo boy with respiratory distress.
Radiology shows a mediastinal mass and a pleural
effusion, which is tapped. Flow cytometry shows
90 of effusion cells are TdT, CD10, CD3,
CD7, CD4 and CD8. Interpretation A. Myeloid
sarcoma B. B lymphoblastic lymphoma C. T
lymphoblastic lymphoma D. Hodgkin
lymphoma E. Reactive process
Comment By morphology and flow cytometry, the
immature cells are T lymphoblasts. An
extramedullary mass of lymphoblasts is called
lymphoblastic lymphoma, although it is part of a
biologic continuum referred to as
leukemia/lymphoma.
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Hx 7 yo boy with an recent onset of vomiting
and lethargy. Blood smear shows increased
neutrophils with a left shift and 8 abnormal
cells. Bone marrow contains 60 of the same
cells. Flow cytometry shows cells are TdT-,
CD10, CD19. Interpretation A. AML B. B-cel
l ALL C. T-cell ALL D. Burkitt
leukemia/lymphoma E. Reactive process
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6
Hx 7 yo boy with recent onset of vomiting and
lethargy. Blood has increased neutrophils with
left shift and 8 abnormal cells. Bone marrow
contains 60 of the same cells. Flow cytometry
shows cells are TdT-, CD10, CD19.
Interpretation A. AML B. B-cell
ALL C. T-cell ALL D. Burkitt
leukemia/lymphoma E. Reactive process
Comment Flow cytometry shows mature B-cells,
and the morphology is that of Burkitt lymphoma,
which occasionally can have a leukemic phase.
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Hx 12 yo boy with vomiting, abdominal pain and
weight loss. Radiology shows an ileo-cecal mass.
Histology of the resection specimen is shown.
Flow cytometry on the mass shows cells are TdT-,
CD10 and CD19. Interpretation A. Myeloid
sarcoma B. B lymphoblastic lymphoma C. T
lymphoblastic lymphoma D. Burkitt
lymphoma E. Reactive process
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Hx 12 yo boy with vomiting, abdominal pain and
weight loss. Radiology shows an ileo-cecal mass.
Histology of the resection specimen is shown.
Flow cytometry on the mass shows cells are TdT-,
CD10 and CD19. Interpretation A. Myeloid
sarcoma B. B lymphoblastic lymphoma C. T
lymphoblastic lymphoma D. Burkitt
lymphoma E. Reactive process
Comment The starry-sky histology can be seen
in either lymphoblastic lymphoma or Burkitt
lymphoma, but the immunophenotype is of a mature
B-cell, consistent with Burkitt lymphoma, and the
appearance of the cells also favors Burkitt
lymphoma.
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Hx 14 yo boy with a single large cervical lymph
node. Lymph node biopsy is shown. Flow
cytometry and immunohistochemistry show cells are
TdT-, CD19, CD20, CD3-. Interpretation A. La
rge B-cell lymphoma B. T lymphoblastic
lymphoma C. Mature (Peripheral) T-cell
lymphoma D. Hodgkin lymphoma E. Reactive
process
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8
Hx 14 yo boy with a single large cervical lymph
node. Lymph node biopsy is shown. Flow
cytometry and immunohistochemistry show cells are
TdT-, CD19, CD20, CD3-. Interpretation A. La
rge B-cell lymphoma B. T lymphoblastic
lymphoma C. Mature (Peripheral) T-cell
lymphoma D. Hodgkin lymphoma E. Reactive
process
Comment The neoplastic cells are large and
monomorphous, with the immunophenotype of mature
B-cells.
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Hx 18 yo boy with abdominal pain, has
hepatosplenomegaly, thrombocytopenia and anemia,
without adenopathy. Flow cytometry on infiltrate
shows cells are TdT-, CD3, CD4-, CD8-.
Interpretation A. B lymphoblastic
lymphoma B. Burkitt lymphoma C. T
lymphoblastic lymphoma D. Mature (Peripheral)
T-cell lymphoma E. Reactive process
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9
Hx 18 yo boy with abdominal pain, has
hepatosplenomegaly, thrombocytopenia and anemia,
without adenopathy. Flow cytometry on infiltrate
shows cells are TdT-, CD3, CD4-, CD8-.
Interpretation A. B lymphoblastic
lymphoma B. Burkitt lymphoma C. T
lymphoblastic lymphoma D. Mature (Peripheral)
T-cell lymphoma E. Reactive process
Comment The infiltrate is monomorphous, with the
immunophenotype of a mature T-cell process,
specifically hepatosplenic T-cell lymphoma, which
typically infiltrates parenchyma rather than
forming a discrete mass.
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Hx 17 yo boy with fever and cervical
lymphadenopathy. Lymph node biopsy shown.
Immunohistochemistry shows cells are CD3-, CD 4,
CD8-, CD30, EMA, ALK. Interpretation A. Bur
kitt lymphoma B. T lymphoblastic
lymphoma C. Mature (Peripheral) T-cell
lymphoma D. Hodgkin lymphoma E. Reactive
process
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10
Hx 17 yo boy with fever and cervical
lymphadenopathy. Lymph node biopsy shown.
Immunohistochemistry shows cells are CD3-, CD4,
CD8-, CD30, EMA, ALK. Interpretation A. Bur
kitt lymphoma B. T lymphoblastic
lymphoma C. Mature (Peripheral) T-cell
lymphoma D. Hodgkin lymphoma E. Reactive
process
Comment The infiltrate is composed of large,
anaplastic cells with a mature T-cell
immunophenotype. In this setting, ALK-positivity
is helpful in calling this anaplastic large cell
lymphoma.
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Hx 13 yo boy with fatigue, weight loss, night
sweats and splenomegaly. Peripheral blood shows
anemia and leukocytosis (300,000/mm3). Ancillary
test results include normal fetal hemoglobin and
karyotype showing t(922). Interpretation A. Ac
ute myeloid leukemia B. Acute lymphoblastic
leukemia C. Chronic myelogenous
leukemia D. Juvenile myelomonocytic
leukemia E. Reactive process
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Hx 13 yo boy with fatigue, weight loss, night
sweats and splenomegaly. Peripheral blood shows
anemia and leukocytosis (300,000/mm3). Ancillary
test results include normal fetal hemoglobin and
karyotype showing t(922). Interpretation A. A
cute myeloid leukemia B. Acute lymphoblastic
leukemia C. Chronic myeloid leukemia D. Juveni
le myelomonocytic leukemia E. Reactive process
Comment Marked leukocytosis with prominent
basophils without increased blasts (lt10)
indicate chronic phase of CML. t(922)(q34q11.2)
indicates a BCR/ABL1 rearrangement.
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12
Hx 2 yo girl with new onset of fever and
bronchitis. Has maculo-papular rash and
hepatosplenomegaly. Blood smear has leukocytosis
(100,000/mm3), anemia and thrombocytopenia.
Ancillary tests include fetal hemoglobin of 80
and normal blood karyotype. Interpretation A.
Acute myeloid leukemia B. Acute lymphoblastic
leukemia C. Chronic myeloid leukemia D. Juveni
le myelomonocytic leukemia E. Reactive process
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12
Hx 2 yo girl with new onset of fever and
bronchitis. Has maculopapular rash and
hepatosplenomegaly. Blood smear has leukocytosis
(100,000/mm3), anemia and thrombocytopenia.
Ancillary tests include fetal hemoglobin of 80
and normal blood karyotype. Interpretation A.
Acute myeloid leukemia B. Acute lymphoblastic
leukemia C. Chronic myeloid leukemia D. Juveni
le myelomonocytic leukemia E. Reactive process
Comment Marked leukocytosis including
monocytosis without increased blasts, accompanied
by erythroid proliferation and elevation of fetal
hemoglobin is characteristic of JMML. BCR/ABL1
fusion is not present.
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Hx 1 yo boy with pallor and a rash. Blood
smear shows pan cytopenia and circulating
abnormal cells. Interpretation A. Acute
myeloid leukemia B. Chronic myelogenous
leukemia C. Acute lymphoblastic
leukemia D. Leukoerythroblastic
reaction E. Infectious mononucleosis
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13
Hx 1 yo boy with pallor and a rash. Blood
smear shows pan cytopenia and circulating
abnormal cells. Interpretation A. Acute
myeloid leukemia B. Chronic myelogenous
leukemia C. Acute lymphoblastic
leukemia D. Leukoerythroblastic
reaction E. Infectious mononucleosis
Comment The large blasts with ample cytoplasm
and prominent nucleoli are suggestive of AML, but
the Auer rod is diagnostic.
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Hx 8 yo boy with bruising. Blood smear shows
anemia, thrombocytopenia, and leukocytosis
(30,000/mm3, 50 blasts). Flow cytometry on
marrow shows 50 blasts with TdT, MPO, CD13,
CD33, partial CD19. Interpretation A. Acute
myeloid leukemia B. Chronic myelogenous
leukemia C. Acute lymphoblastic
leukemia D. Myelodysplastic syndrome E. Reacti
ve process
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14
Hx 8 yo boy with bruising. Blood smear shows
anemia, thrombocytopenia, and leukocytosis
(30,000/mm3, 50 blasts). Flow cytometry on
marrow shows 50 blasts with TdT, MPO, CD13,
CD33. Interpretation A. Acute myeloid
leukemia B. Chronic myelogenous
leukemia C. Acute lymphoblastic
leukemia D. Myelodysplastic syndrome E. Reacti
ve process
Comment The elevated blast count indicates
acute leukemia. Auer rod is diagnostic of a
myeloid neoplasm, and flow cytometry agrees.
Morphology shows myeloid maturation and a large
blunt Auer rod, which often correlates with
t(821)(q22q22) and RUNX1/RUNX1T1 fusion.
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Hx 8 yo girl with fever, tonsillitis and
lymph-adenopathy. Blood smear shows anemia,
thrombocytopenia, and leukocytosis (140,000/mm3,
60 blasts). Flow cytometry on marrow shows 60
blasts with TdT, MPO, CD13, CD33, CD11b
partial. Interpretation A. Acute myeloid
leukemia B. Chronic myelogenous
leukemia C. Acute lymphoblastic
leukemia D. Chediak-Higashi syndrome E. Reacti
ve process
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15
Hx 8 yo girl with fever, tonsillitis and
lympha-denopathy. Blood smear shows anemia,
thrombocytopenia, and leukocytosis (140,000/mm3,
60 blasts). Flow cytometry on marrow shows 60
blasts with tdT, MPO, CD13, CD33, CD11b
partial. Interpretation A. Acute myeloid
leukemia B. Chronic myeloid leukemia C. Acute
lymphoblastic leukemia D. Chediak-Higashi
syndrome E. Reactive process
Comment Increased blasts mark as myelomonocytic
lineage, so this is AML. The strange, darkly
granulated cells are abnormal eosinophils,
morphology that correlates with a karyotype of
inv(16) or t(1616).
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Hx 13 yo girl with fever and swelling of one
leg. Blood smear shows anemia and
thrombo-cytopenia. WBC 3400/mm3 with marked left
shift. Marrow has 2 blasts but 82 immature
myeloid cells as shown. Flow cytometry on marrow
shows MPO, CD33, CD13 partial, HLA-DR-,
CD34-. Interpretation A. Acute myeloid
leukemia B. Chronic myelogenous
leukemia C. Acute lymphoblastic
leukemia D. Mast cell leukemia E. Left shift
with toxic granulation
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16
Hx 13 yo girl with fever and swelling of one
leg. Blood smear shows anemia and
thrombocytopenia. WBC 3400/mm3 with marked left
shift. Marrow has 2 blasts but 82 immature
myeloid cells as shown. Flow cytometry on marrow
shows MPO, CD33, HLA-DR-, CD34-.
Interpretation A. Acute myeloid
leukemia B. Chronic myelogenous
leukemia C. Acute lymphoblastic
leukemia D. Mast cell leukemia E. Left shift
with toxic granulation
Comment Proliferating promyelocytes, which
sometimes have multiple Auer rods, rather than
myeloblasts characterize the acute promyelocytic
form of AML, which is associated with t(1517)
and a PML/RARA fusion.
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Hx 19 yo girl with history of treatment for
ALCL 3 years prior. Now with persistent
pancytopenia (WBC 800/mm3, no circulating
blasts). Marrow has 80 abnormal cells that by
flow cytometry are MPO-, CD33, CD34-, CD13,
CD11b, CD14. Interpretation A. Acute
myeloid leukemia B. Juvenile myelomonocytic
leukemia C. Acute lymphoblastic
leukemia D. Langerhans cell histiocytosis E. H
emophagocytic lymphohistiocytosis
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Hx 19 yo girl with history of treatment for
ALCL 3 years prior. Now with persistent
pancytopenia (WBC 800/mm3, no circulating
blasts). Marrow has 80 abnormal cells that by
flow cytometry are MPO-, CD33, CD34-, CD13,
CD11b, CD14. Interpretation A. Acute
myeloid leukemia B. Juvenile myelomonocytic
leukemia C. Acute lymphoblastic
leukemia D. Langerhans cell histiocytosis E. H
emophagocytic lymphohistiocytosis
Comment The morphology and flow cytometry are
those of monoblasts, which is characteristic of
therapy-related AML, especially with
rearrangements of the MLL gene at chromosome
11q23.
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Hx 1yo boy with pallor and bruising. Blood
shows anemia and thrombocytopenia, with mild
leukocytosis (10,000/mm3, 5 circulating blasts).
Marrow has 60 abnormal cells that by flow
cytometry are MPO-, CD33, HLA-DR-, CD34-,
glycophorin A(CD235a). Interpretation A. Acut
e myeloid leukemia B. Juvenile myelomonocytic
leukemia C. Acute lymphoblastic
leukemia D. Burkitt lymphoma/leukemia E. Chron
ic parvovirus infection
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18
Hx 1yo boy with pallor and bruising. Blood
shows anemia and thrombocytopenia, with mild
leukocytosis (10,000/mm3, 5 circulating blasts).
Marrow has 60 abnormal cells that by flow
cytometry are MPO-, CD33, HLA-DR-, CD34-,
glycophorin A(CD235a). Interpretation A. Acut
e myeloid leukemia B. Juvenile myelomonocytic
leukemia C. Acute lymphoblastic
leukemia D. Burkitt lymphoma/leukemia E. Chron
ic parvovirus infection
Comment The morphology and immunophenotype
indicate a pure erythroid proliferation of
blasts, without a significant myeloid component,
making this the pure erythroid variant of AML.
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Hx 1 yo boy with fever and weight loss. Blood
shows anemia and neutropenia with 5 circulating
blasts. Marrow has 95 abnormal cells that by
flow cytometry are MPO-, CD33, CD34-, HLA-DR-,
CD41, CD61. Interpretation A. Acute myeloid
leukemia B. Acute lymphoblastic
leukemia C. Transient myeloproliferative
disorder D. Neuroblastoma E. Langerhans cell
histiocytosis
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Hx 1 yo boy with fever and weight loss. Blood
shows anemia and neutropenia with 5 circulating
blasts. Marrow has 95 abnormal cells that by
flow cytometry are MPO-, CD33, CD34-, HLA-DR-,
CD41, CD61. Interpretation A. Acute myeloid
leukemia B. Acute lymphoblastic
leukemia C. Transient myeloproliferative
disorder D. Neuroblastoma E. Langerhans cell
histiocytosis
Comment The immunophenotype and marrow
replacement indicate the megakaryoblastic variant
of AML. Megakaryoblasts may be small, resembling
lymphoblasts. Platelet-like cytoplasmic buds are
common but not specific.
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Hx 17 yo boy with inguinal lymphadenopathy. On
biopsy, nodal architecture is effaced by a
vaguely nodular proliferation of large atypical
cells and small lymphocytes. By
immuno-histochemistry, the large cells are CD20,
CD45, BCL6, EMA, Oct 2, BOB1, but CD15- and
CD30-. Interpretation A. Chronic lymphocytic
lymphoma B. Burkitt lymphoma C. Classic
Hodgkin lymphoma D. Nodular lymphocyte-predomina
nt Hodgkin lymphoma E. Reactive process
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Hx 17 yo boy with inguinal lymphadenopathy. On
biopsy, nodal architecture is effaced by a
vaguely nodular proliferation of large atypical
cells and small lymphocytes. By
immuno-histochemistry, the large cells are CD20,
CD45, BCL6, EMA, Oct 2, BOB1, but CD15- and
CD30-. Interpretation A. Chronic lymphocytic
lymphoma B. Burkitt lymphoma C. Classic
Hodgkin lymphoma D. Nodular lymphocyte-predomina
nt Hodgkin lymphoma E. Reactive process

Comment The morphology and B-cell
immunophenotype are characteristic of the LH
cells (popcorn cells) of nodular
lymphocyte-predominant Hodgkin lymphoma.
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Hx 17 yo boy with fever, night sweats, weight
loss andcervical lymphadenopathy . On biopsy,
nodal architecture is effaced by mixed
inflammatory cells and large atypical cells. The
large cells are CD30, CD15, PAX5 weak, but
CD20-, CD45-, EMA-, Oct 2-, BOB1-.
Interpretation A. Chronic lymphocytic
lymphoma B. Burkitt lymphoma C. Classical
Hodgkin lymphoma D. Nodular lymphocyte-predomina
nt Hodgkin lymphoma E. Reactive process
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21
Hx 17 yo boy with fever, night sweats, weight
loss andcervical lymphadenopathy . On biopsy,
nodal architecture is effaced by mixed
inflammatory cells and large atypical cells. The
large cells are CD30, CD15, PAX5 weak, but
CD20-, CD45-, EMA-, Oct 2-, BOB1-.
Interpretation A. Chronic lymphocytic
lymphoma B. Burkitt lymphoma C. Classical
Hodgkin lymphoma D. Nodular lymphocyte-predomina
nt Hodgkin lymphoma E. Reactive process
Comment The morphology and immunophenotype are
characteristic of the Hodgkin cells and
Reed-Sternberg cells of the classical form of
Hodgkin lymphoma.
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Hx 5 yo boy, 2yrs post liver transplant, with
new onset of lymphadenopathy and ascites.
Radiology shows a right lower quadrant mass. A
bone marrow aspirate contained the cells shown,
which are CD20 and show in situ hybridization
for EBV. Interpretation A. Acute myeloid
leukemia B. Acute lymphoblastic
leukemia C. Post-transplant lymphoproliferative
disorder D. Infectious mononucleosis E. He
mophagocytic lymphohistiocytosis
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22
Hx 5 yo boy, 2yrs post liver transplant, with
new onset of lymphadenopathy and ascites. A bone
marrow aspirate contains the cells shown, which
are CD20 and show in situ hybridization for EBV.
Interpretation A. Acute myeloid
leukemia B. Acute lymphoblastic
leukemia C. Post-transplant lymphoproliferative
disorder D. Infectious mononucleosis E. He
mophagocytic lymphohistiocytosis

Comment The morphology and immunophenotype fit
a large B-cell lymphoma, which here represents a
mono-morphous post-transplant lymphoproliferative
disorder.
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Hx 4 yo boy with a small painless frontal bone
mass, which was resected. Radiology shows
multiple lytic bony defects. The cells in the
mass are CD1a, S100, but are CD68-.
Interpretation A. Myeloid sarcoma B. Peripher
al T-cell lymphoma C. Metastatic solid
tumor D. Langerhans cell histiocytosis E. Infe
ctious granulomatous process
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23
Hx 4 yo boy with a small painless frontal bone
mass, which was resected. Radiology shows
multiple lytic bony defects. The cells in the
mass are CD1a, S100, but are CD68-.
Interpretation A. Myeloid sarcoma B. Peripher
al T-cell lymphoma C. Metastatic solid
tumor D. Langerhans cell histiocytosis E. Infe
ctious granulomatous process
Comment The morphology of twisted and reniform
histiocytes with nuclear grooves, and the
distinctive immunophenotype are those of
Langerhans cells. The eosinophils are helpful
but not essential.
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Hx 6 mo girl with a large abdominal mass and
elevated serum catecholamines. Bone marrow
aspirations contains the cells pictured. Flow
cytometry shows the cells to be CD56.
Interpretation A. Myeloid leukemia/sarcoma B.
Lymphoblastic leukemia/lymphoma C. Natural
killer cell lymphoma D. Metastatic Wilms
tumor E. Metastatic neuroblastoma
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24
Hx 6 mo girl with a large abdominal mass and
elevated serum catecholamines. Bone marrow
aspirations contains the cells pictured. Flow
cytometry shows the cells to be CD56.
Interpretation A. Myeloid leukemia/sarcoma B.
Lymphoblastic leukemia/lymphoma C. Natural
killer cell lymphoma D. Metastatic Wilms
tumor E. Metastatic neuroblastoma
Comment Clumps of small cells are most likely
solid tumor. CD56 not only marks natural killer
cells but is also a neural cell adhesion
molecule. Small cell tumor with elevated
catecholamines is diagnostic of neuroblastoma.