T12 haematopathology WBC

reactive proliferations of white cells

chronic nonspecific lymphadenitis (reactive)

chronic nonspecific lymphadenitis (reactive) - diseases

follicular hyperplasia, paracortical hyperplasia, sinus histiocytosis (reticular hyperplasia)

follicular hyperplasia - what is it

proliferation of B cells in lymphoid follicles

follicular hyperplasia - zone

cortical

follicular hyperplasia - causes

rheumatoid arthritis, toxoplasmosis, early HIV infection

follicular hyperplasia - microscopic features

follicles vary in size, clear cut boundary, tingible body macrophages (starry sky)

tingible body macrophages

contains apoptosis bodies

paracortical hyperplasia - what is it

expansion of T cells zone

paracortical hyperplasia - cause

viral infection

paracortical hyperplasia - zone

paracortex

sinus histiocytosis (reticular hyperplasia) - what is it

expansion of sinusoidal macrophages

neoplastic proliferations of white cells

lymphoid neoplasm & myeloid neoplasm

lymphoid neoplasm - includes

precursor B & T cells, peripheral B cells, peripheral T cells & NK cells

myeloid neoplasm - includes

chronic myeloproliferative disorders

precursor B & T cells neoplasm - aka

lymphoblastic leukemia/lymphoma

precursor B & T cells neoplasm - common in

children

precursor B & T cells neoplasm - pre-B ALL

acute leukemia in children

precursor B & T cells neoplasm - pre-T ALL

thymic lymphoma in adolescent males

precursor B & T cells neoplasm - chromosomal translocation

t(9;22)

precursor B & T cells neoplasm - gene mutation

BCR-ALB1 → philadelphia chromosome

precursor B & T cells neoplasm - pathophysio

activate tyrosine kinase mutations

precursor B & T cells neoplasm - immunophenotype

TdT → marker for lymphoblast

precursor B & T cells neoplasm - clinical features

bone pain & tenderness, lymphadenopathy, splenomegaly, CNS involvement, thymic mass

precursor B & T cells neoplasm - prognosis

highly cured with chemotherapy

precursor B & T cells neoplasm - microscopic features

lymphoblast in bone marrow & blood → scant basophilic cytoplasm, large nucleus

peripheral B cells - diseases

follicular lymphoma, diffuse large B cell lymphoma, burkitt lymphoma, multiple myeloma, mantle cell lymphoma

most common non-hodgkin lymphoma in adults

follicular lymphoma

follicular lymphoma - affects who

middle-aged

follicular lymphoma - chromosomal translocation

t(14;18)

follicular lymphoma - gene mutation

BCL2

BCL2

prevents apoptosis → accumulation of B cells

follicular lymphoma - clinical features

enlarged lymph nodes, can transform to diffuse large B cell lymphoma

follicular lymphoma - prognosis

incurable but indolent

follicular lymphoma - microscopic features

centrocytes, centroblasts, same size follicles, ill-defined borders of germinal centres, no tingible body macrophage

most common lymphoma in adults

diffuse large B cell lymphoma

diffuse large B cell lymphoma - 30% gene mutation

BCL6

diffuse large B cell lymphoma - 10% gene mutation

BCL2

diffuse large B cell lymphoma - 10% chromosome translocation

t(14;18)

diffuse large B cell lymphoma - 10% develop from

follicular lymphoma

diffuse large B cell lymphoma - immunophenotype

CD19 & CD20 → B cell markers

diffuse large B cell lymphoma - clinical features

rapidly enlarge symptomatic mass

diffuse large B cell lymphoma - prognosis

50% cured

diffuse large B cell lymphoma - microscopic features

diffuse effacement of lymph node architecture, large cells, vesicular nucleus (2-3 nucleoli)

burkitt lymphoma - latently infected by

EBV

burkitt lymphoma - key note

very aggressive B cell tumor

burkitt lymphoma - chromosome translocation

t(8;14)

burkitt lymphoma - gene mutation

MYC proto-oncogene

burkitt lymphoma - pathophysio

MYC overexpression → uncontrolled cell cycle progression

burkitt lymphoma - immunophenotype

CD19 & CD20 → B cell markers

burkitt lymphoma - clinical features

rapidly growing mass at mandible, ileocecal area, peritoneum

burkitt lymphoma - prognosis

good response to chemotherapy

burkitt lymphoma - microscopic features

medium sized cell, starry sky pattern

multiple myeloma - what is it

plasma cell neoplasm

multiple myeloma - common in

65-70 yrs old

multiple myeloma - immunophenotype

CD138 → plasma cell markers

multiple myeloma - clinical features

hypercalcemia, renal failure, amyloidosis, bony lesion, back pain

multiple myeloma - destructive bone lesion

osteolytic activity

multiple myeloma - hypercalcemia

bone resorption

multiple myeloma - renal failure

light chains proteins

multiple myeloma - cause of death

infection / chronic kidney disease

multiple myeloma - microscopic features

punched out lesions, abnormal plasma cells, rouleaux formation, bence jones proteins

mantle cell lymphoma - what is it

tumor of naive B cells

mantle cell lymphoma - chromosome translocation

t(11;14)

mantle cell lymphoma - pathophysio

increase cyclin D1 → uncontrolled cell cycle progression

mantle cell lymphoma - immunophenotype

CD19, CD20, cyclin D1

mantle cell lymphoma - clinical featues

lymphadenopathy

mantle cell lymphoma - microscopic features

small lymphocytes, cleaved or non-cleaved nuclei

peripheral T cells & NK cells - disease

hodgkin lymphoma

hodgkin lymphoma - characteristics

arise in single lymph node or chain → spread predictably

hodgkin lymphoma - associated with

EBV

hodgkin lymphoma - pathophysio

RS cells secrete cytokines / chemokines to recruit inflammatory cells & promote proliferation of other cells

hodgkin lymphoma - key cell

reed-sternberg (RS)

reed-sternberg (RS) cell - what is it

neoplastic giant cells derived from germinal centers of B cells

reed-sternberg (RS) cell - secrete what

cytokines / chemokines

cytokines / chemokines from RS cells

recruit inflammatory cells & promote proliferation of other cells

hodgkin lymphoma - immunophenotype

CD15, CD30, PAX5 (no expression of B cell markers)

hodgkin lymphoma - clinical features

enlarged lymph nodes

hodgkin lymphoma - microscopic features

reed-sternberg (RS) cells & all other reactive cells

reed-sternberg (RS) cells - features

large, multiple nucleus, large inclusion-like nucleolus, abundant cytoplasm → owl’s eyes

reed-sternberg (RS) cells - markers

CD15 & CD30