Hematopoietic Neoplasia Flashcards
Breeds with high incidence of lymphoma
boxers, bullmastifs, bassets, st bernards, scottish terriers, airedales, pit bulls, briards, irish setters, rottweilers, and bulldogs
low risk - dachshunds and pomeranians
cant believe not goldens
what genetic alteration has been shown to have a prognostic advantage for dogs with lymphoma
trisomy of chromosome 13 - increased duration of first remission
what mutation has been proven in golden retrievers with lymphoma
somatic mutations leading to deficiencies in DNA repair mechanisms
Environmental factors implicated in lymphoma
exposure to tobacco, proximity to environmental waste, strong magnetic field proximity, lawn care products (2,4-D), maybe helicobacter
not flea and tick products
all are really unproven
immunologic factors associated with lymphoma development
ITP
one case of cyclosporin treatment
one atopic dermatitis and epitheliotropic lsa report - unknown if its the disease process or the treatments
prevalence of different lymphoma forms in dogs
multicentric - 80%
alimentary - 5-7%
mediastinal - 5 %
what dog breed has been shown to develop GI lymphoma from lymphocytic plasmacytic IBD
Basenjis
breeds association for GI lymphoma in dogs
shar-pei and boxer
prevalence of hypercalcemia in mediastinal lsa
10-40%
most commonly t cell
single case of gamma delta t cell lsa with large granular lymphs
cutaneous lymphoma phenotype
usually CD8+ t cells - in humans CD4
circulating cells = sezary syndrome (seen in dogs and cats)
non-epitheliotropic lymphoma definition histologically
spare the epidermis and papillary dermis and affect the middle and deep dermis and sq
phenotype of hepatosplenic lymphoma
gamma delta T cells - extremely aggressive
same in humans
intravascular (angiotropic) lymphoma-
what is it?
what anatomic locations is it associated with?
phenotype/
lymphocytes within the lumen of bloodvessels but no distinct mass or leukemia
includes CNS, peripheral nervous system and the eye
b cell is most common phenotype in humans but in dogs seems to be t cell or null cell, one b cell case report
what clinical sign is more common with mediastinal lymphoma than others
pre caval syndrome - pitting edema of the head neck and forelimbs due to compression or invasion of the cranial vena cava
phenotype and cns distribution of lymphoma
b cell = meningeal, perivascular, and periventricular
t cell = peripheral nerves
pathophysiology of hypercalcemia in lymphoma
may be pthrp
may also be IL1 TNFa TGFb and vit d analogs being released
what percent of multicentric lymphoma dogs will have radiographic changes to their chest
60-75%
1/3 have pulmonary infiltrates
2/3 have thoracic lymphadenopathy
can see pulm effusion
cxr pattern of pulmonary lymphoma infiltrates
usually interstitial to alveolar
rare bronchial
most common lab abnormality of a dog with lymphoma
anemia
frequency of thrombocytopenia
frequency of neutrophilia
frequency of lymphocytosis
thrombocytopenia 30 - 50% of cases
neutrophilia 25-40%
lymphocytosis 20%
frequency of monoclonal gamopathy in lsa
6%
large cell lymphoma cytologic characteristics
2 x rbc and larger than neut
visible nucleoli and basophilic cytoplasm with or without perinuclear clearing zone
fin chromatic with indistinct nucleoli
T cell markers
CD3 - pan T
CD4 - t helper
cd8 - cytoxic t
b cell markers
CD79a, CD20, CD21
indolent tzone can express CD21
sensitivity of parr for lsa in dogs
70-90%
5% fasle positive
Immunophenotype for
DLBCL
CD1+, CD20+ CD21+ CD45+ CD79a+, Pax5+ MCHII+ CD18 low
Immunophenotype for
peripheral t cell lymphoma
CD3+, CD79a–, CD21–, CD45+, CD5+, CD4+/–, CD8+/–, CD18high, TCRαβ
Immunophenotype for
marginal zone lymphoma
and histologic features
- nodal or splenic or extranodal mucosa
- nodular or follicular on histo
- intermediate sized cells
- rare mitotic activity - except nodal
- CD1+, CD20+, CD21+, CD45+,
CD79a+, MHCII+, CD18inter- mediate - similar to dlbcl but smaller sized cells
Immunophenotype for
Tzone lymphoma and histologic features
- CD45–, CD3+, CD5+, CD21+, CD4+/–, CD8+/–
- small to intermediate size with rare mitotic figures
Immunophenotype for
precursor t cell lymphoma
+ features
CD45+, CD34+/–, CD5+/–, CD3+/–, CD4+/–, CD8–
diffuse or leukemia
intermediate sized
high MC
Immunophenotype for
precursor b cell lymphoma
+ features
CD45+, CD18+, CD34+/–, CD79a+, CD21+/–, CD20+/–
diffuse or leukemia
intermediate sized
high MC
Immunophenotype for
mantle cell lymphoma
+ histologic features
- splenic white pulp
- nodular/follicular
- small to intermediate sized and variable MC
- CD20+, CD21+, CD45+, CD79a+, MHCII+
Immunophenotype for
follicular lymphoma
+ histologic features
- solitary or multiple lymph nodes
- mixed cell size mostly small 1-3 nucleoli
- CD20+, CD21+, CD45+, CD79a+, MHCII+
common causes of a false + parr
ehrlichiosis leishmaniasis
What percent of dogs with lymphoma are at least stage III at the time of diagnosis?
> 80%
What are myeloproliferative neoplasm (MPNs)? List different myeloproliferative neoplasms
- Characterized by excessive production of differentiated bone marrow cells
- Polycythemia vera, CML, essential thrombocythemia, primary myelofibrosis
What percent of dogs with multicentric lymphoma have thoracic involvement based on chest x-rays?
60-75%
1/3rd with pulmonary involvement, 2/3rd with lymphadenopathy
Most common AML subtypes in decreasing frequency
- Monocytic leukemia (M5a, M5b) - 42%
- myelomonocytic leukemia (M4) - 33%
- myeloblastic leukemia without differentiation (M1) - 13%
- megakaryoblastic leukemia (M7) - 5%
What AML subtype has not been identified in dogs?
acute promyelocytic leukemia (M3)
What mutation is associated with humans with polycythemia vera? This has been identified in 1 out of 5 dogs with PV.
JAK2
True or false: Both immature and mature neutrophils are present in CML
True
What chromosomal translocation is present in humans with CML? What is the analogous translocation in dogs?
In humans: Philadelphia chromosome (BCR-ABL translocation between chromosomes 9 and 22)
In dogs: “Raleigh Chromosome” (BCR-ABL translocation between chromosomes 9 and 26)
What characterizes an essential thrombocythemia?
Platelets consistently >600,000/uL with other causes of thrombocytosis ruled out (inflammation, IMHA, iron deficiency anemia, rebound from ITP, splenectomy, cancer)
What is myelodysplastic syndrome (MDS)?
Dysfunction of the bone marrow which usually presents with cytopenias in two or three cell lines. Sometimes referred to as preleukemia because it may progress to acute leukemia.
In polycythemia vera what is the typical PCV?
65-85%
What staining is used for neutrophil differentiation in AML?
Positive staining of blasts for peroxidase, Sudan Black B, and chloracetate
What staining is used for monocyte differentiation in AML?
Nonspecific esterases (α-naphthyl acetate esterase or α-naphthyl butyrate esterase)
What staining is used for megakaryocytes in AML?
Acetylcholinesterase; Also von Willebrand’s factor and platelet glycoproteins for megakaryocyte precursors
Is ALP a useful marker for AML?
Recent study indicated it was useful in a diagnosis of AML if neoplastic cells express only CD34
What cancers are CD34+ on flow?
ALL and AML