USMLE Hem Onc Flashcards
EBV is associated with what cancers?
HL, NHL, Nasopharyngeal Carcinoma
What complication might people who receive more than one body’s worth of transfusions experience?
Hypocalcemia as citrate binds up calcium
Shifting partial pressure of O2 at 50% Hb concentration from 26-20 mmHg will result in what response?
Erythrocytosis b/c left shift = higher affinity
What is the mechanism behind megaloblastic macrocytic anemia?
Diminished thymidine synthesis
What do you use to rapidly reverse warfarin?
Fresh frozen plasma
What serum level do you monitor for DIC?
Serum fibrinogen
What does blocking the HIV gp41 protein inhibit?
Viral penetration into the cells
What drug do you use to prevent DIC in pregnancy?
Heparin
What kind of receptor is JAK2?
Non-receptor tyrosine kinase
Biopsy reveals uniform, round medium-size tumour cells with basophilic cytoplasm and a proliferation fraction (Ki-67 fraction) of >99%. Dx and cause?
Burkitt’s lymphoma from EBV infection.
What drugs do you have to watch out for when using methotrexate/6MP/6TG?
Allopurinol and febuxostat b/c block xanthine oxidase, which metabolizes MTX/6MP
Where is vWF released from?
Weibel Palade bodies and platelets
Platelet binding onto vWF leads to the release of what chemicals?
ADP (promotes GpIIbIIIa expression) and TxA2
Transient vasoconstriction in response to bleeding is triggered by?
Neural stimulation and endothelin
What should be on your differential for a presentation of hemophilia A/B/C?
Coagulation factor inhibitor, distinguish with a mixing study
What test do you use to follow liver failure?
PT
How do you diagnose VWD?
With a ristocetin cofactor assay test showing decreased agglutination
How do you differentiate between DIC and a disorder of fibrinolysis?
PC is normal and no D-dimer (only fibrinogen broken down) in fibrinolysis disorders
Squamous cells and keratin debris in clot. What kind of clot is it?
Amniotic fluid clot.
Vessel thrombosis, lens subluxation, mental disability, and long slender fingers. Dx?
Cystathionine beta synthase deficiency (requires B6 to convert homocysteine to cystathionine)
Embolus with cholesterol crystals. What kind is it?
Atherosclerotic
Lymphocytic lymphocytosis. DDx?
Viral infections (handled by CD8+ T cells) B. Pertussis
Eosinophilia ddx?
Parasites, allergy, Hodgkin Lymphoma **via increased IL-5
Basophilia ddx?
CML
Monocytosis ddx?
Chronic inflammation, malignancy
What cancer do you expect in kids with Down syndrome > 5 y/o and children generally?
ALL
What cancer do you expect in kids with DS
Acute megakaryoblastic leukemia
Lymphocytes with smudge cells that are CD5 and CD20 positive. Dx?
Chronic lymphocytic leukemia (of naive B cells)
What’s the most serious complication of CLL?
Transformation into large B cell lymphoma
Leukemia that infiltrates the gums. Dx?
Acute monoblastic leukemia
Blasts that are positive for MPO and Auer rods?
AML
Blasts that are positive for tDt (DNA polymerase)?
ALL
What distinguishes CML from a typical lymphoid reaction?
LAP -ve, t9:22, basophilia
Itching post bathing - what disease and why?
Polycythemia vera b/c of mast cells
What distinguishes PV from typical reactive polycythemia?
Reactive polycythemia = low SaO2, high Epo.
PV = normal SaO2, low Epo.
How do you distinguish follicular lymphoma from normal LAD from infection?
1) No white spaces in germinal centres
2) Monoclonality
3) Bcl2 expression in follicles
Teardrop cell with leukoerythroblastic smear and splenomegaly. Dx?
Myelofibrosis (Myeloproliferative d/o)
Painless LAD with proliferation that expands region immediately adjacent to the follicle. Dx?
Mantle Cell Lymphoma
What diseases put you at risk for a marginal zone lymphoma?
Hashimoto’s, Sjogren’s, H. pylori gastritis (MALToma)
LAD with high mitotic rate and starry sky appearance. Dx?
Burkitt lymphoma
Bulk of LAD is reactive cells and fibrosis. Dx?
Hodgkin’s Lymphoma
Lymph node bx divided by broad bands of fibrosis?
Hodgkin’s Lymphoma, nodular sclerosis subtype (most common)
Spoon shaped nails, anemia, pica. Dx?
IDA
What are some causes of B12 deficiency?
Pernicious anemia, Pancreatic insufficiency, damage to the terminal ileum (Crohn’s)
How do you differentiate between B12 and folate deficiency macrocytic anemia?
Methylmalonic acid is high in B12, normal in folate.
Increased RDW and MCHC, splenomegaly with macrophage hypertrophy. Dx?
Hereditary spherocytosis
What conditions do you see spherocytes in?
Major Sickle Spheres
B-thal Major
Sickle Cell Anemia
Hereditary spherocytosis
5 month old kid comes in with swollen hands and feet. Dx?
Sickle Cell Disease
What is the most common cause of death in paroxysmal nocturnal hemoglobinuria?
Thrombosis b/c complement attacks platelets and causes activation of coagulation cascade.
What are you in danger of progressing to in PNH?
AML b/c of acquired mutation in myeloid stem cells
What are you in danger of progressing to in PNH?
AML b/c of acquired mutation in myeloid stem cells
Why does the PTT rise in vWD?
Because vWF escorts F VIII
Heinz bodies and bite cells in blood. Dx
G6PD deficiency
A person comes with a Mycoplasma or infectious mono infection with anemia. What kind of anemia is it?
IHA, cold agglutinin, IgM
What do you give to reverse heparin?
Protamine sulfate
What is leucovorin used for?
Rescues BM in MTX, can’t in 5-FU
t8:14
Burkitt Lymphoma (c-myc)
IL3
like GMCSF
t9:22
Philadelphia Chromosome Bcr Abl CML
t11:14
Mantle Cell Lymphoma (cyclin D1 activation)
t14:18
Follicular Lymphoma (BCl2)
t15:17
Acute promyelocytic leukemia (Vit A, tx with ATRA)