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Anatomic pathology > Spleen > Flashcards

Flashcards in Spleen Deck (256):
1

Splenomegaly associated with systemic lupus erythematosus or with rheumatoid arthritis: Other findings (2).

Neutropenia.

Leg ulcers.

2

Reactive lymphoid hyperplasia without germinal centers: Cells (3).

Heterogeneous population of lymphocytes.

Immunoblasts.

Tingible-body macrophages.

3

Reactive lymphoid hyperplasia without germinal centers: Locations of infiltrate.

White pulp, including the periarteriolar lymphoid sheaths.

Infiltration of the trabeculae may lead to splenic rupture.

4

Castleman's disease of the spleen: Most common type.

Plasma-cell type.

The hyaline-vascular type rarely or never occurs.

5

Castleman's disease of the spleen: Types of multicentric disease.

Plasma-cell type.

Plasmablastic type.

6

Reactive follicular hyperplasia with formation of germinal centers: Gross pathology.

Nodularity of white pulp.

7

Castleman's disease of the spleen: Histology of the plasma-cell type (2).

Hyperplastic or regressively transformed follicles.

Many plasma cells in the red pulp.

8

Castleman's disease of the spleen: Histology of the plasmablastic type.

Fibrosis and many plasma cells surround hyperplastic or regressively transformed follicles.

Unremarkable red pulp.

Mantle zones contain immunoblastoid and plasmablastoid cells.

9

Castleman's disease of the spleen: Microlymphoma.

Aggregates of HHV8-positive plasmablasts.

10

Castleman's disease of the spleen: Immunophenotype of plasmablasts (4,1).

Positive: CD20, IgM, lambda light chain, HHV8.

Negative: CD30.

11

Castleman's disease of the spleen: Laboratory finding associated with multicentric disease.

Increased IL-6 in the serum.

12

Castleman's disease of the spleen: Complication of the plasmablastic type.

Development of plasmablastic lymphoma.

13

Common variable immunodeficiency: Gross appearance of spleen.

May be enlarged or unremarkable.

14

Common variable immunodeficiency: Histology of splenic follicles

May be atrophic, hyperplastic, or normal.

May exhibit atypical follicular hyperplasia.

15

Common variable immunodeficiency: Other possible histologic features (3).

Granulomas.

Immunoblasts and Reed-Sternberg-like cells.

Lymphoid hyperplasia in the red pulp.

16

Common variable immunodeficiency: Viral association.

In most cases, EBV is detectable by

- Immunohistochemical stain for LMP.
- In-situ hybridization for EBV (EBER).

17

Common variable immunodeficiency: Lymphocytes.

Mixture of T cells and B cells.

18

Common variable immunodeficiency vs. lymphoma (2).

Lymphoma:

- (Usually) no established history of immunodeficiency.
- Demonstrated clonality.

19

Castleman's disease of the spleen: Viral associations of plasmablastic type.

HHV8, with or without HIV.

20

Autoimmune lymphoproliferative syndrome: Presentation.

Generalized lymphadenopathy, splenomegaly, and autoimmune disease in a child under 2 years of age.

21

Autoimmune lymphoproliferative syndrome: Aetiology.

Mutation in Fas, Fas ligand, caspase 8, or caspase 10.

22

Autoimmune lymphoproliferative syndrome: Manifestation in peripheral blood.

Autoimmune cytopenias.

23

Autoimmune lymphoproliferative syndrome: Complication.

Hodgkin's lymphoma or non-Hodgkin's lymphoma.

24

Autoimmune lymphoproliferative syndrome: Histology (3).

White pulp: Follicular hyperplasia, expansion of germinal centers.

Red pulp: Expansion by T cells and plasma cells.

PALS: Same as for red pulp.

25

Autoimmune lymphoproliferative syndrome: Immunohistochemistry (2).

Double-negative T lymphocytes, mainly in the red pulp.

No expression of CD25.

26

Splenic marginal-zone lymphoma: Typical presentation.

Massive splenomegaly.

27

Splenic marginal-zone lymphoma: Manifestations in peripheral blood (2).

Autoimmune anaemia.

Thrombocytopenia.

28

Splenic marginal-zone lymphoma: Additional possible laboratory findings (2).

Monoclonal IgM or IgD.

Cryoglobulinemia.

29

Splenic marginal-zone lymphoma: Affected organs.

Splenic hilar lymph nodes, peripheral blood, bone marrow, and liver may all be involved at presentation.

Peripheral lymph nodes are not affected.

30

Splenic marginal-zone lymphoma: Infectious association.

Hepatitis C.

31

Splenic marginal-zone lymphoma: Gross pathology.

Miliary pattern due to expansion of white pulp.

32

Splenic marginal-zone lymphoma: Histology.

White pulp: Expansion of marginal zones, or colonization of germinal centers with attenuation of mantle zones.

Red pulp: Diffuse or nodular infiltrate.

33

Splenic marginal-zone lymphoma: Cytology (2).

Most cells . . .
- Nucleus: Round to oval.
- Cytoplasm: Clear, often abundant.

Larger lymphoid cells at the periphery of the nodules.

34

Splenic marginal-zone lymphoma: Appearance in peripheral blood.

Abundant cytoplasm and short polar villi.

35

Splenic marginal-zone lymphoma: Immunophenotype.

Positive: Usual B-cell markers.

Negative: Specific markers.

36

Splenic marginal-zone lymphoma vs. splenic diffuse red-pulp small B-cell lymphoma

SDRPSBCL:

- Diffuse infiltration of red pulp with obliteration of white pulp.
- Strongly expresses DBA.44 and often expresses CD11c.

37

CLL/SLL of the spleen: Gross pathology.

Earlier: Miliary pattern due to expansion of white pulp.

Advanced disease: More homogenous appearance due to diffuse disease.

38

CLL/SLL of the spleen: Histology.

White pulp: Diffuse neoplastic infiltrate replaces germinal centers.

Red pulp: Diffuse neoplastic infiltrate.

Proliferation centers are rare in the spleen.

39

CLL/SLL of the spleen: Types.

Pre-germinal-center type:
- Unmutated IGVH.
- Often express ZAP-70 and CD38.

Memory-B-cell type: Opposite.

40

CLL/SLL of the spleen vs. prolymphocytic leukemia: Immunophenotype (4).

Prolymphocytic leukemia:

- Stronger CD20 and sIg.
- Expression of FMC7.
- Variable CD5.

41

Reactive follicular hyperplasia with formation of germinal centers: Histology (3).

Follicles consist of a germinal center and well-defined mantle and marginal zones.

Germinal centers are polarized (with dark and light zones) and contain tingible-body macrophages.

Increased plasma cells in the red pulp.

42

Reactive follicular hyperplasia with formation of germinal centers: Immunohistochemistry of germinal centers (3,1).

Positive: CD20, CD10, Bcl-6.

Negative: Bcl-2.

43

Reactive follicular hyperplasia with formation of germinal centers: Immunohistochemistry of mantle zones (3,2).

Positive: CD20, CD5, Bcl-2.

Negative: CD43, cyclin D1.

44

Relevance of well-developed splenic germinal centers to age.

Children and young adults: Normal.

Elderly: May represent lymphoma or autoimmune disease.

45

Prominent expansion of splenic marginal zone: Cause.

Chronic antigenic stimulation.

46

Prominent expansion of splenic marginal zone vs. marginal-zone lymphoma

Marginal-zone lymphoma:

- Marginal-zone cells infiltrate germinal centers and red pulp.
- Mantle zone is effaced.

47

Splenomegaly associated with systemic lupus erythematosus or with rheumatoid arthritis: Histology (3).

Follicular hyperplasia.

Plasmacytosis.

Expansion of the red pulp.

48

Splenomegaly associated with systemic lupus erythematosus or with rheumatoid arthritis: Immunophenotype.

T lymphocytes that cause expansion of the red pulp lack CD3 and CD8 and express CD57.

48

Prolymphocytic leukemia: Criterion.

At least 55% of circulating lymphocytes are prolymphocytes.

49

Prolymphocytic leukemia: Presentation (3).

Massive splenomegaly.

Cytopenias (due to hypersplenism).

No lymphadenopathy.

50

Prolymphocytic leukemia: Involved pulp.

Diffuse infiltration of red pulp.

White usually also involved.

51

Prolymphocytic leukemia: Cytology.

Prolymphocytes:

- Medium size.
- Much cytoplasm.
- Large nucleolus.

52

Prolymphocytic leukemia: Immunohistochemistry.

B-cell PLL
- Positive: CD20.
- Variable: CD5, CD23.

T-cell PLL
- Positive: CD3, CD4, CD5.
- May lose T-cell antigens.

53

Mantle-cell lymphoma: Presentations (2).

Usual: Widespread lymphadenopathy, disease in bone marrow.

Splenomegalic: Leukemia, no lymphadenopathy.

54

Mantle-cell lymphoma: Involved pulp.

White pulp.

55

Mantle-cell lymphoma: Histology.

Nodular expansion of white pulp with or without a mantle-zone pattern.

A purely mantle-zone pattern of growth is rare.

56

Mantle-cell lymphoma: Cytology of blastoid variant.

Blastoid cells may resemble lymphoblasts or the large, pleomorphic cells or DLBCL.

57

Mantle-cell lymphoma: Immunophenotype (4,1).

Positive: CD20, CD5, cyclin D1, SOX11.

Negative: CD23.

58

Mantle-cell lymphoma: Function of cyclin D1.

Regulates progression of G1 phase to S phase.

59

Follicular lymphoma: Frequency of splenic disease.

About 50%.

60

Follicular lymphoma: Involvement of pulp.

Involves white pulp mainly.

The red pulp may contain small aggregates of lymphoma cells.

61

Follicular lymphoma: Frequency of lack of expression of Bcl-2.

About 20%.

62

Diffuse large B-cell lymphoma: Gross pathology (2).

Large nodules of tumor, often with necrosis.

Involvement of hilar and retroperitoneal lymph nodes.

63

Diffuse large B-cell lymphoma: Involved pulp.

Involves both white and red pulp, effacing the splenic architecture.

64

Hodgkin's lymphoma: Frequency of disease in the spleen (2).

Primary splenic Hodgkin's lymphoma is exceedingly rare.

NLP-HD rarely involves the spleen.

65

Gaucher's disease:

A. Defective enzyme.
B. Storage product.

A. Glucocerebrosidase (beta-glucosidase).

B. Glucocerebroside.

66

Gaucher's disease: Clinical forms.

Infantile form: Hepatosplenomegaly, mental deterioration, death in infancy of early childhood.

Adult form.

67

Gaucher's disease, adult form:

A. Epidemiology.
B. Age of onset.
C. Presentation.

A. Most common in Ashkenazi Jews.

B. Late childhood or adulthood.

C. No mental retardation; pancytopenia may occur.

68

Gaucher's disease: Affected pulp.

Red pulp.

69

Gaucher's disease, adult form: Affected organs (4).

Liver.

Spleen.

Adrenal glands.

Bones.

70

Gaucher's disease: Cytology.

Brown, "wrinkled-silk" cytoplasm.

71

Gaucher's disease: Special stains (4).

Positive: PAS with and without diastase, iron stain.

Colorless on Wright's stain.

72

Gaucher's disease: Histologic differential diagnosis (2).

Niemann-Pick disease: Foamy or bubbly cytoplasm.

Ceroid histiocytes: Faintly yellow-brown on H and E but blue-green on Wright-Giemsa stain.

73

Gaucher's disease: Electron microscopy.

Lysosomes contain twisted helical tubules.

74

Niemann-Pick disease:

A. Defective enzyme.
B. Storage product.

A. Sphingomyelinase.

B. Sphingomyelin.

75

Niemann-Pick disease: Affected organs (5).

Spleen.

Liver.

Lungs.

Brain.

Bone marrow.

76

Niemann-Pick disease: Cytology.

Yellow-green, foamy or bubbly cytoplasm.

77

Niemann-Pick disease: Special stains (2).

Positive: AFB stain.

Blue-green on Wright-Giemsa stain.

78

Niemann-Pick disease: Electron microscopy.

Variably sized residual bodies.

79

Mucopolysaccharidoses:

A. Appearance on routine stain.
B. Special stain.

A. Clear cytoplasm.

B. Weakly positive: PAS without diastase.

80

Mucopolysaccharidoses: Electron microscopy.

Membrane-bound vacuoles with lamellar inclusions.

81

Glycogen-storage diseases:

A. Appearance on routine stain.
B. Special stain.

A. Clear cytoplasm.

B. Positive: PAS without diastase.

82

Glycogen-storage diseases: Electron microscopy.

Glycogen granules.

83

Extramedullary hematopoiesis: Types.

Non-neoplastic.

Neoplastic: The extramedullary hematopoiesis is itself malignant.

84

Extramedullary hematopoiesis, non-neoplastic: Causes (3).

Severe anemia.

Myelophthisis

Normal fetal state or prematurity.

85

Extramedullary hematopoiesis, non-neoplastic: Presentation.

Usually asymptomatic; incidental finding.

86

Extramedullary hematopoiesis, neoplastic type: Presentation.

Pain due to splenomegaly or splenic infarcts.

Cytopenias.

87

Extramedullary hematopoiesis, non-neoplastic: Causes (2).

Myeloproliferative neoplasms, esp. primary myelofibrosis.

MDS/MPNs.

88

Extramedullary hematopoiesis, non-neoplastic: Differential diagnosis.

Non-neoplastic EMH.

Extramedullary acute leukemia.

89

Extramedullary hematopoiesis: Affected pulp.

Red pulp.

90

Hereditary spherocytosis: Histology (4).

Cords: Distended; increased macrophages.

Sinuses: Empty; hypertrophic lining cells.

Little erythrophagocytosis.

Minimal hemosiderin.

91

Fibrocongestive splenomegaly: Association.

Liver disease.

92

Fibrocongestive splenomegaly:

A. Histology.
B. Differential diagnosis.

A. Fibrosis and congestion.

B. Capillary hemangioma and splenic hamartoma are usually better circumscribed.

93

Sickle-cell disease: Causes of sepsis.

Haemophilus influenzae.

Streptococcus pneumoniae.

Neisseria meningitidis.

94

Gross appearance of spleen in ___.

A. HbSS disease.
B. Hemoglobin C disease.

A. Shrunken and fibrotic due to total infarction.

B. Possibly enlarged; infarction may be focal but is never total.

95

Sickle-cell disease: First part of the spleen to be affected.

The follicles.

96

Gamna-Gandy body.

Old organized microinfarct that is encrusted with iron.

Typical but not specific for sickle-cell disease.

97

Autoimmune hemolytic anemia: Histology (4).

White pulp: Follicular hyperplasia.

Red pulp:
- Increased plasma cells.
- Erythrophagocytosis.
- Congested cords; empty-appearing sinuses.

98

Evans' syndrome.

ITP + hemolytic anemia.

99

Immune thrombocytopenic purpura: Clinical forms.

Acute: More common in children.

Chronic: More common in middle-aged.

100

Immune thrombocytopenic purpura: Histology of spleen (4).

White pulp: Follicular hyperplasia.

Red pulp:
- "Dirty"-appearing cordal macrophages due to ingested platelets.
- Foamy macrophages.
- Increased neutrophils.

101

Immune thrombocytopenic purpura: Histology of bone marrow.

Megakaryocytes may be increased.

102

Immune thrombocytopenic purpura: Role of spleen (2).

Destruction of platelets.

Production of anti-platelet antibodies.

103

Immune thrombocytopenic purpura: Indication of splenectomy.

Failure to respond to steroids.

104

Splenic diffuse red-pulp small B-cell lymphoma: Involved pulp.

Red pulp.

White pulp is atrophic.

105

Splenic diffuse red-pulp small B-cell lymphoma: Cytology (2).

Small to medium-sized lymphoid cells.

Nucleus: Round; occasional small distinct nucleoli.

106

Splenic diffuse red-pulp small B-cell lymphoma: Other involved organs (3).

Bone marrow: Intrasinusoidal infiltrate.

Peripheral blood: Villous lymphocytes.

Skin: Dermal infiltrate surrounding adnexa and blood vessels; epidermotropism.

107

Splenic diffuse red-pulp small B-cell lymphoma vs. splenic marginal-zone lymphoma.

Splenic marginal-zone lymphoma involves both white pulp and red pulp.

108

Splenic diffuse red-pulp small B-cell lymphoma vs. hairy-cell-leukemia variant.

HCL-v: At least some lymphoid cells have large nucleoli.

109

Splenic diffuse red-pulp small B-cell lymphoma: Immunohistochemistry (1,2,2).

Positive: DBA.44.

Variable: CD103, CD11c.

Negative: Annexin A-1, CD25.

110

Hairy-cell leukemia: Clinical presentation (4).

Splenomegaly, anemia, infections.

No lymphadenopathy.

111

Hairy-cell leukemia: Most specific marker.

CD103.

112

Hairy-cell leukemia: Involved pulp.

Red pulp.

White pulp may be obliterated.

113

Hairy-cell leukemia: Histology.

Hairy cells in cord and sinuses.

Hairy cells form periphery of blood lakes.

114

Hairy-cell-leukemia: Cytology.

Nucleus: Inconspicuous nucleolus.

Cytoplasm: Villi.

115

Hairy-cell leukemia: Morphologic variants.

Larger cells.

Blastoid cells.

116

Hairy-cell leukemia: Special stain.

Reticulin stain reveals fibers surrounding the hairy cells.

117

Hairy-cell leukemia: Immunophenotype (6).

Positive: CD103, CD11c, CD25, TRAP, DBA.44, annexin A1, FMC7.

118

Hairy-cell leukemia: Mutation.

V600E in BRAF.

119

Hairy-cell-leukemia variant: Sites of involvement.

Spleen.

Peripheral blood.

Bone marrow: More easily aspirated than in classic HCL.

Liver and lymph nodes are usually spared.

120

Hairy-cell-leukemia variant: Involved pulp.

Red pulp.

White pulp is atrophic.

121

Hairy-cell-leukemia variant: Histology.

Blood lakes may be visible.

122

Hairy-cell-leukemia variant: Cytology.

Nucleus: Round or bilobate; large nucleolus.

Cytoplasm: Basophilic; many villi.

May resemble prolymphocytic leukemia or classic HCL.

123

Hepatosplenic T-cell lymphoma: Association.

Prolonged immunosuppression.

Lymphoma may first appear in a transplanted organ.

124

Hepatosplenic T-cell lymphoma: Presentation (3).

Hepatosplenomegaly.

Cytopenias.

"B" symptoms.

125

Hepatosplenic T-cell lymphoma: Involved pulp.

Red pulp.

White pulp is obliterated.

126

Hepatosplenic T-cell lymphoma: Histology.

Tumor cells distend sinuses and may form sheets.

127

Hepatosplenic T-cell lymphoma: Cytology.

Nucleus: Oval or folded; inconspicuous nucleolus.

Cytoplasm: Pale.

128

Hairy-cell-leukemia variant: Immunophenotype (2,1,3).

Positive: DBA.44, CD11c.

Variable: CD103.

Negative: CD25, TRAP, annexin A1.

129

Hepatosplenic T-cell lymphoma: Pattern of disease in bone marrow.

Intravascular.

Clusters of tumor cells.

130

Hepatosplenic T-cell lymphoma: Expressed markers (3).

CD3, CD56, TIA-1.

131

Hepatosplenic T-cell lymphoma: Unexpressed markers (6).

CD4, CD8.

CD5.

CD57.

Granzyme B, perforin.

132

Hepatosplenic T-cell lymphoma: Flow cytometry.

Most cases have the gamma-delta TCR.

A few have the alpha-beta TCR.

133

Large-granular-lymphocytic leukemia: Presentation (3).

Neutropenia with or without anemia.

Moderate splenomegaly.

Variable lymphocytosis.

134

Large-granular-lymphocytic leukemia: Immunophenotypes.

T-LGL expresses CD3, CD8, alpha-beta TCR, granzyme B.

NK-LGL expresses CD16, CD56, cCD3.

135

Hepatosplenic T-cell lymphoma: Prognosis.

Median survival is less than 2 years.

136

Hepatosplenic T-cell lymphoma: Mutation.

i(7q).

137

Systemic mastocytosis: Involved pulp.

Red pulp.

138

Systemic mastocytosis:

A. Composition of nodules.
B. Location of nodules.

A. Mast cells, eosinophils, fibrosis.

B. Perivascular, peritrabecular, perifollicular.

139

Systemic mastocytosis: Possible morphologies of mast cells (4).

Spindled.

May resemble
- Monocytes.
- Monocytoid B cells.
- Hairy cells.

140

Systemic mastocytosis: Immunophenotypic abnormality.

Expression of CD25 and (often) CD2.

141

Systemic mastocytosis: Laboratory finding.

Elevated serum tryptase.

142

Langerhans'-cell histiocytosis: Involved pulp.

Red pulp.

143

Langerhans'-cell histiocytosis: Patterns of infiltrate (2).

Diffuse.

Multinodular (granulomatoid).

Discrete tumor masses are rare.

144

Langerhans'-cell histiocytosis: Nucleus of tumor cell.

Pale and bean-shaped.

145

Langerhans'-cell histiocytosis: Accompanying cells.

Eosinophils and plasma cells, although much less numerous than in "eosinophilic granuloma".

146

Systemic mastocytosis: Mutation.

D816V in KIT.

147

Histiocytic sarcoma: Presentation.

Serious illness; cytopenias.

148

Histiocytic sarcoma: Involved pulp.

Red pulp.

Bone marrow is usually also involved.

149

Histiocytic sarcoma: Cytology.

Highly atypical cells with large nucleoli and ,any mitotic figures.

150

Histiocytic sarcoma: Additional histologic feature.

Erythrophagocytosis by macrophages (but not by tumor cells).

151

Histiocytic sarcoma: Immunohistochemistry (2,1,1).

Positive: CD68, CD163.

Variable: S100.

Negative: CD1a.

152

Splenic hemangioma: Possible complications (2).

Cytopenias due to hypersplenism.

Consumptive coagulopathy (DIC).

153

Splenic hemangioma: Most common type.

Cavernous.

154

Splenic hemangioma: Incompatible histologic features (2).

Endothelial tufting.

Endothelial mitotic figures (except in children).

155

Splenic hemangioma: Immunohistochemistry (1,2).

Positive: Vascular markers.

Negative: Hematopoietic markers, Ki-67.

156

Splenic angiomatosis.

Diffuse replacement of spleen by hemangioma.

157

Peliosis of the spleen: Association.

Peliosis hepatis.

158

Peliosis of the spleen:

A. Location.
B. Possible complication.

A. Diffuse or multifocal in the spleen.

B. Splenic rupture.

159

Peliosis of the spleen: Histology.

Dilated sinuses lined by flattened cells and surrounded by splenic parenchyma.

No fibrosis.

160

Peliosis of the spleen: Immunohistochemistry (2).

Positive: CD68, CD8.

161

Myoid angioendothelioma: Histology.

Consists of

- Vascular spaces.
- Stromal cells with myoid features.

162

Vascular marker that is usually not expressed by lymphatic vessels.

CD34.

163

Littoral-cell angioma: Presentation.

May cause splenomegaly and hypersplenism.

164

Littoral-cell angioma: Gross pathology.

May be multiple (in contrast to hemangioma); rarely replaces the whole spleen.

165

Littoral-cell angioma: Architecture (2).

Variable-shaped vascular spaces lined by littoral cells.

Papillae of littoral cells may project into vascular spaces.

166

Littoral-cell angioma: Cytology (2).

Bland, cuboidal or hobnail-shaped cells with few mitotic figures.

Nuclei: Large and vesicular.

167

Littoral-cell angioma: Incompatible histologic features (2).

Solid growth.

Necrosis.

168

Littoral-cell angioma: Special stains (2).

Reticulin: Annular fibers around vascular spaces.

PAS: Cytoplasmic globules.

169

Littoral-cell angioma: Expressed markers (6).

CD31, CD68, CD68R, CD21, CD163.

S100 sometimes.

170

Littoral-cell angioma vs. normal littoral cells: Immunophenotype.

Normal littoral cells express CD8.

171

Littoral-cell angioma: Unexpressed markers (2).

CD8, CD34.

172

Splenic angiosarcoma: Associations.

Not associated with thorium dioxide or with vinyl chloride.

173

Splenic angiosarcoma: Gross pathology (2).

Splenomegaly, often marked.

May be multiple.

174

Splenic angiosarcoma: Architecture (3).

Irregular anastomosing vascular channels.

May show solid growth.

Papillae may project into vascular spaces.

175

Splenic angiosarcoma: Cytology

Variable shape of cells.

Mild to severe atypia.

Variable mitotic activity.

176

Splenic angiosarcoma: Possible additional histologic features (2).

Extramedullary hematopoiesis.

Erythrophagocytosis.

177

Splenic angiosarcoma: Most consistently expressed vascular markers.

CD31.

Ulex lectin.

178

Splenic angiosarcoma: Electron microscopy.

Weibel-Palade bodies.

179

Splenic angiosarcoma vs. hemangioendothelioma (4).

Hemangioendothelioma:

- No necrosis.
- No solid growth.
- Less atypia.
- Fewer mitotic figures.

180

Splenic angiosarcoma vs. hemangiopericytoma (4).

Hemangiopericytoma:

- No necrosis.
- Little or no atypia.
- Fewer mitotic figures.
- Spindle cells surround rather than form vascular spaces.

181

Splenic angiosarcoma vs. bacillary angiomatosis (4).

Bacillary angiomatosis:

- No anastomosing vascular channels.
- Little or no atypia.
- Few mitotic figures.
- Basophilic clumps of bacteria.

182

Epidermoid cyst of the spleen: Presentation.

Asymptomatic unless infected.

183

Littoral-cell angioma vs. hemangioendothelioma (2).

Hemangioendothelioma:

- Hyperchromatic nuclei.
- Usually no expression of CD68.

184

Epidermoid cyst of the spleen: Gross pathology (2).

Lining: Shiny, trabeculated.

Contents: Turbid yellow fluid.

185

Epidermoid cyst of the spleen: Histology.

Thin wall lined by squamous, transitional, or columnar epithelium.

186

Epidermoid cyst of the spleen: Putative histologic origin.

Mesothelium.

187

Pseudocyst of the spleen: Presentation.

Asymptomatic unless infected.

188

Pseudocyst of the spleen: Putative aetiology.

Degeneration of traumatic splenic hematoma or of splenic infarct.

189

Pseudocyst of the spleen: Gross pathology (2).

Lining: Smooth (not trabeculated).

Contents: Dark red-brown fluid.

190

Pseudocyst of the spleen: Histology (2).

Fibrous wall without epithelial lining.

Calcifications in wall.

191

Echinococcal cyst of the spleen: Risk factors (2).

Exposure to livestock or deer.

Exposure to feces of canids.

192

Echinococcal cyst of the spleen: Gross pathology (3).

Often multilocular.

Granular lining.

Granules in the contents.

193

Splenic hamartoma: Gross pathology.

Usually solitary, well-circumscribed, red, bulging nodule.

194

Splenic hamartoma: Histology

Consists of elements of red pulp: Cord-like and sinus-like structure.

Compressed red pulp at the periphery, but no capsule.

May contain foci of infarction and fibrosis.

195

Splenic hamartoma, cordal variant.

Consists mainly of cordal macrophages.

May resemble inflammatory pseudotumor.

196

Splenic hamartoma: Immunohistochemistry of normal splenic endothelium (2,1).

Positive: CD8, CD68.

Negative: CD34.

197

Inflammatory pseudotumor of the spleen: Gross pathology.

Usually solitary, well-circumscribed, pale, bulging nodule, often with central necrosis.

198

Inflammatory pseudotumor of the spleen: Variants.

"Truly inflammatory" type: Older patients.

Hepatosplenic-IPT-like tumor of follicular dendritic cells: Mostly in females.

199

Inflammatory pseudotumor of the spleen: Cellular components.

Bland spindle cells.

Lymphocytes, plasma cells, macrophages, neutrophils.

Few or no eosinophils.

200

Inflammatory pseudotumor of the spleen: Association.

Hepatosplenic-IPT-like tumor of follicular dendritic cells consistently harbors EBV-DNA.

201

Inflammatory pseudotumor of the spleen: General immunohistochemistry (2,1).

Positive: MSA, SMA.

Variable: Desmin.

202

Inflammatory pseudotumor of the spleen: Special immunohistochemistry.

"Truly inflammatory variant": Expression of CD68 but not of FDC markers.

Hepatosplenic-IPT-like tumor of follicular dendritic cells: Expression of CD21, CD23, CD35, EBV-LMP.

203

Inflammatory pseudotumor of the spleen: Additional immunohistochemistry.

An increased ratio of IgG4 to IgG should prompt a search for evidence (e.g. chronic pancreatitis) of IgG4-related disease.

204

Inflammatory pseudotumor of the spleen: Differential diagnosis in patients with AIDS (2).

Mycobacterial pseudotumor.

Bacillary angiomatosis.

205

Inflammatory pseudotumor of the spleen vs. inflammatory myofibroblastic tumor.

Inflammatory myofibroblastic tumor:

- Clonal myofibroblasts.
- Expresses ALK.

206

Congestive splenomegaly: Causes (2).

Cirrhosis of the liver.

Thrombosis of the splenic vein (PNH, PV).

207

Congestive splenomegaly: Gross pathology (2).

Expanded red pulp; inconspicuous white pulp.

Spleen usually weighs less than 1 kg.

208

Congestive splenomegaly: Evolution of histology.

Early: Cellular red pulp.

Later:
- Hypocellular red pulp with reticulin fibrosis.
- Dilated sinuses due to fibrotic retraction.
- Gamna-Gandy bodies may occur.

209

Fibrocongestive splenomegaly:

A. Synonym.
B. Immunohistochemistry.

A. Chronic passive congestion of the spleen.

B. Increased expression of SMA due to proliferation of splenic myoid cells.

210

Congestive splenomegaly vs. splenic hamartoma.

Splenic hamartoma is well circumscribed.

211

Splenic hamartoma vs. hemangioma.

Hemangioma

- Contains organized vascular spaces.
- Expresses CD34 but not CD8 or CD68.

212

Vasculitis in the spleen: Gross pathology (2).

Infarcts.

Splenic rupture has been reported.

213

Polyarteritis nodosa: Type of affected blood vessel.

Small artery.

214

Polyarteritis nodosa: Histology (2).

Fibrinoid necrosis.

Neutrophils and eosinophils in the walls of the vessels.

215

Churg-Strauss syndrome: Synonym.

Hypersensitivity angiitis.

216

Churg-Strauss syndrome: Histology in the spleen (3).

Arterioles: Leukocytoclastic vasculitis.

Small vessels: Fibrinoid necrosis.

Eosinophils.

217

Systemic lupus erythematosus: Histology in the spleen (4).

Arterioles:
- Leukocytoclastic vasculitis.
- Perivascular fibrosis ("onion-skin" appearance).

Small vessels: Fibrinoid necrosis.

Plasmacytosis in red pulp.

218

Rheumatoid arthritis: Histology in the spleen (3).

Arterioles: Leukocytoclastic vasculitis.

Small vessels: Fibrinoid necrosis.

Follicular hyperplasia in the white pulp.

219

TTP: Histology in the spleen (4).

Arterioles: Perivascular fibrosis sometimes.

Small vessels:
- Thrombi consisting of platelets and fibrin.
- No inflammation.

Subendothelial PAS-positive hyaline deposits.

220

Thromboemboli: Types that cause true vasculitis.

Septic emboli.

Emboli of endocarditis.

221

Infectious mononucleosis: Gross pathology.

Red pulp: Congestion.

White pulp: Hyperplasia.

Spontaneous rupture can occur.

222

Infectious mononucleosis: Histology (4).

Red pulp: Expansion by lymphocytes, immunoblasts, plasma cells.

White pulp: Follicular hyperplasia.

Periarteriolar lymphoid sheaths: Lymphoid cells including immunoblasts.

Lymphoid cells may infiltrate trabeculae and capsule.

223

Infectious mononucleosis: Immunohistochemistry of immunoblasts (2,1).

Positive: CD20, EBV.

Often positive: CD30.

224

Infectious mononucleosis: T lymphocytes.

Mainly cytotoxic, CD8+.

225

Infectious mononucleosis vs. lymphoma: Gross pathology.

Lymphomas (both Hodgkin's and non-Hodgkin's) tend to form discrete masses in the spleen.

226

Cytomegalovirus infection of the spleen: Complication.

Virus-associated hematophagocytic syndrome: Fever, chills, malaise, and pancytopenia.

227

Cytomegalovirus infection of the spleen: Gross pathology.

Red pulp: Congestion.

White pulp: Usually inconspicuous.

228

Mycobacterium avium-intracellulare infection of the spleen: Laboratory finding.

Anemia.

229

Mycobacterium avium-intracellulare infection of the spleen: Involved pulp.

Red pulp: Firmly expanded.

230

Mycobacterium avium-intracellulare infection of the spleen: Histology (2).

Histiocytes appear pale gray on routine stain.

There may be erythrophagocytosis.

231

Mycobacterium avium-intracellulare infection of the spleen: Special stains.

Tissue: AFB, PAS.

Cytology: Wright, Papanicolaou.

232

Malaria in the spleen: Leading cause of splenomegaly.

Plasmodium vivax.

233

Malaria in the spleen, acute phase: Gross pathology.

Red-brown parenchyma due to congestion and malarial pigment.

234

Malaria in the spleen, acute phase: Histology

Venous sinuses engorged with parasitized red cells.

Sinus macrophages contain hemosiderin, red cells, malarial pigment.

Increase small lymphocytes in the red pulp.

235

Malaria in the spleen, acute phase: Cells that contain parasites.

Erythrocytes.

Sinus-lining cells sometimes.

236

Malaria in the spleen, chronic phase: Gross pathology.

Gray parenchyma with fibrosis and scarring.

237

Malaria in the spleen, chronic phase: Histology (2).

Fibrosis and scarring.

Pigment-laden macrophages in the PALS.

238

Hyperactive malarial splenomegaly: Association.

Chronic malarial infection in endemic areas.

239

Hyperactive malarial splenomegaly: Histology (2).

Hyperplasia of sinusoids and of reticuloendothelial system.

Intense splenic sequestration with erythrophagocytosis.

240

Malaria in the spleen, chronic phase: Another possible manifestation.

Splenic pseudocyst.

241

Properties of malarial pigment (3).

Refractile.

Birefringent.

Negative on iron stain.

242

Abscess vs. infarct:

A. Consistency.
B. Location of greatest inflammation.

A. Abscess is soft or liquid; infarct is firm.

B. In the center of an abscess; in the periphery of an infarct.

243

Miliary tuberculosis of the spleen: Gross pathology.

Granulomas are often less well formed and lack visible necrosis.

244

Lipogranulomatosis.

Presence of lipid matter derived endogenous sources, e.g. tumors, hematomas, cholesterol deposits.

245

Lipogranulomatosis:

A. Gross pathology.
B. Histology.

A. Not seen grossly.

B. Lipid vacuoles surrounded by macrophages; located near arterioles in the white pulp.

246

Splenic ___: Affected pulp.

A. sarcoidosis
B. miliary tuberculosis
C. histoplasmosis
D. coccidioidomycosis

A. White pulp.

B. Both.

C. Red pulp more than white pulp.

D. Both.

247

Splenic histoplasmosis, acute phase: Histology (3).

May lack discrete granulomas.

Histiocytes, plasma cells, lymphocytes.

Usually no neutrophils.

248

Splenic histoplasmosis, inactive phase: Histology (2).

Calcification and fibrosis surrounded by a few lymphocytes.

Usually no histiocytes.

249

Origin of __ amyloid.

A. AL.
B. AA.

A. Immunoglobulin light chains, especially lambda.

B. SAA protein.

250

Causes of AA-type amyloidosis (3).

Tuberculosis.

Rheumatoid arthritis.

Other chronic inflammatory diseases.

251

Splenic amyloidosis: Gross pathology.

Incidental: Grossly inapparent.

Sago spleen: Nodular.

Lardaceous spleen: Diffuse.

252

Splenic amyloidosis: Location of deposits.

Incidental: Around small vessels.

Sago spleen: White pulp.

Lardaceous spleen: Red pulp near sinuses and around small vessels.

253

Familial Mediterranean fever: Gene.

MEFV.

254

Splenic hyalinosis:

A. Age group.
B. Histology.
C. Cause.

A. Any age after early childhood.

B. Hyaline thickening of small arteries and arterioles.

C. Deposition of plasma proteins.

255

Amyloidosis vs. splenic hyalinosis.

Splenic hyalinosis: No reaction with Congo red or thioflavin T stain.