Canine Lymphoma Flashcards
Etiologic factors
- Chromosome abberations (gain 13 & 31, loss of 14)
- Germline and somatic mutations (TRAF3-MAP3k14, FBXW7, POT1)
- Alterations/deficiencies in DNA repair mech (goldens)
- +/- Helicobacter (?)
- +/- Phenoxyacetic acid herbicides (2,4-D)
- +/- Residency in industrial areas and exposure to solvents
- +/- Exposure to strong magnetic fields (weak)
- +/- Proximity to environmental waste
- Exposure to tobacco smoke (one study)
- Impaired immune function (related to primary disease vs immunosuppressive therapy)
DLBCL Characteristics
CD1+, CD20+ CD21+, CD45+, CD79a+, Pax5+, MCHII+, CD18-low
Architecture: diffuse
PTCL-NOS Characteristics
CD3+, CD79a-, CD21-, CD45+, CD5+, CD4+/-, CD8+/-, CD18-high, TCR-alpha-beta
Location: multicentric
Architecture: diffuse
MZL Characteristics
CD1+, CD20+, CD21+, CD45+, CD79a+, MHCII+, CD18-intermediate
Location: multicentric
Architecture: nodular/follicular
TZL Characteristics
CD45-, CD3+, CD5+, CD21+, CD4+/-, CD8+/-
Location: Multicentric
Architecture: nodular, paracortical, progressing to diffuse
Precursor lymphoma Characteristics
T Cell: CD45+, CD34+/-, CD5+/-, CD3+/-, CD4+/-, CD8-
B Cell: CD45+, CD18+, CD34+/-, CD79a+, CD21+/-, CD20+/-
Location: multicentric and/or leukemia
Architecture: diffuse and/or leukemia
MCL Characteristics
CD20+, CD21+, CD45+, CD79a+, MHCII+
Location: splenic white pulp
Architecture: nodular/follicular
Follicular lymphoma Characteristics
CD20+, CD21+, CD45+, CD79a+, MCHII+
Location: lymphadenopathy, solitary or multiple
Architecture: nodular/ follicular
Strong negative prognostic factors (strong)
- High/intermediate grade
- T cell phenotype
- Low MCH class II expression
- Subtage b
- Gene expression analysis (?)
- Anatomic location (leukemia, cutaneous, GI, hepatosplenic)
- Anemia
- Prolonged steroid pre-treatment
- +/- neutrophilia, thombocytopenia (modest)
Modest negative prognostic factors
- Stage V disease with bone marrow involvement
- Females and neutered females
- Neutrophilia
- Low neutrophil/lymphocyte ratio
- Thrombocytopenia
- Low lymphocyte/monocyte ratio
- Measures of proliferation (contradictory reports)
- +/- geographic location
Negative prognostic biomarkers
Increased:
1. Lactate dehydrogenase activity
2. Thymidine kinase activity
3. Haptoglobin
4. Serum VEGF
5. Glutathione-S-transferase
6. Calcium
Decreased:
1. Serum coblamin
2. Serum albumin
Other:
Serum C- reactive protein - may characterize remission status; variable levels preclude utility
Pulmonary infiltrates
27-34% of dogs with multicentric lymphoma
Gastrointestinal lymphoma
5-7%
Boxers, Shar-peis
Most often multiple segments, can be focal
Can be difficult to distinguish from LP-IBD
Usually T cell with epitheliotropism
Mediastinal lymphoma
~5%
T cell (single case gamma delta T cell with large granular morphology)
Hypercalcemia
Cutaneous lymphoma
Epitheliotropic: T cell, commonly CD8+ (CD4 in poeople)
Sezary syndrome: Cutaneous + circulating large malignant T cells (rare)
Non epitheliotropic: spares epidermis and papillary dermis
Inflamed form: difficult to ddx from reactive histiocytosis
Hepatosplenic
Uncommon
Delta gamma T cells
Lack of significant peripheral lymphadenopathy
Aggressive
Intravascular
Angiotropic or angioendotheliomatosis
Proliferation of neoplastic lymphocytes within lumen and wall of vessels
Absence of leukemia
Usually CNS and PNS
T cell or null cell most commonly reported in dogs (B cell in people)
Mediastinal lymphoma
~5%
T cell (single case gamma delta T cell with large granular morphology)
Hypercalcemia