Rx_2.26 (HemOnc) Flashcards Preview

USMLE Step 1 > Rx_2.26 (HemOnc) > Flashcards

Flashcards in Rx_2.26 (HemOnc) Deck (22)
1

Most common supratentorial tumor in children....

  • craniopharyngioma <== Rathke's pouch
    • ==> H/A, BTH
    • ==> deficiency of ant. pituitary hormones
      • e.g. GH
  • cystic tumor lined by stratified squamous and filled w/viscous yellow, cholesterol rich fluid

2

Warfarin: MOA, toxocity

  • MOA =
    • inhibits vit K epoxide reducatase ==>
    • inability to carboxylate factors II, VII, IX, X  and proteins C & S
  • Toxicity
    • bleeding
    • teratogenic
    • skin/tissue necpsis

3

Classic signs & sx of Hodgkin's Lymphoma

  • night sweats
  • fever
  • weight loss
  • **presence of Reed-Sternberg cell

4

Tx of Hodgkin's lymphoma

  • ​ABVD regimen:
    • Adriamycin (doxorubicin)
    • Bleomycin
    • Vinblastine
    • Dacarbazine

5

Vinblastine: MOA, SE

  • MOA:
    • inhibits MT formation of mitotic spindle
  • SE:
    • alopecia
    • constipation
    • myelosuppression
    • neurotoxicity (rare)

6

abnormal monoclonal immunoglobulin level + no other signs of malignancy ==> dx? tx?

  • monoclonal gammopathy of undeterined significance (MGUS)
  • tx = monitoring @ regular intervals for progression

7

Cancer drugs that act in the M phase of the cell cycle

  • vinca alkaloids=inhibit MT fxn/spindle formation
    • vincristine
    • vinblastine
  • paclitaxel 
    • binds to tubulin and hyperstabilizes MTs that have already polymerized ==> prevents spindle breakdown

8

5-fluorouracil: MOA, use

  • anti-metabolite
  • prevents formation of thymidine vua inhibition of thymidylate synthase
  • use = cancer drug

9

6-mercaptopurine: MOA, use

  • anti-metabolite
  • inhibits formation of purines
  • use = cancer drug

10

Methotrexate: MOA, use

  • anti-metabolite
  • inhibts dihydrofolate reductase ==> inhibition of DNA synthesis (via same pathway as 5-fluorouracil)
  • use = cancer drug

11

Busulfan: MOA, use

  • DNA alkylating agent (cell cyle nonspecific)
  • use = CML

12

Bleomycin: MOA

  • inhibit replication by inducing DNA strand breaks via free radical formation
  • strand breakage interrupts G2 phase of cell cycle (after DNA synthesis)

13

Cyclophosphamide: MOA

  • DNA alkylating agent (cell cycle nonspecific)

14

Hematologic consequences of colon cancer

  • carcinoma of colon ==> chronic blood loss
  • ==> iron deficiency anemia
    • hypochromic, microcytic anemia

15

Iron toxicity presentation & tx

  • N/V + abdominal pain w/in 4 hours of ingestion
  • tx = deferoxamine = chelating agent
    • also tx for aluminum toxicity

16

Deferoxamine: uses, SE

  • use
    • iron toxicity
    • aluminum toxicity
  • SE
    • hypotensive shock 2o to histamine release
    • allergic rxn
    • (rare) neural/renal toxicity

17

Dimercaprol use

  • tx poisoning by arsenic, mercury, gold

18

Penicillamine uses

  • tx of lead and arsenic toxicity
  • chelating agent in Wilson's disease (disorder of copper metabolism)

19

"WEPT"

  • Warfarin Extrinsic, PT
    • Warfarin ==I extrinsic pathway
      • TF + 7 => 10 + 5 => 2 => 1
    • Monitor PT

20

Characteristics of Ehrlichiosis

  • cause = Ehrlichia chaffeensis
    • carried by a tick on dogs/deer in Americas
    • member of the order Rickettsia
  • presentation
    • fever, H/A malaise
    • truncal rash
    • blood = berry-like cytoplasmic inclusion in macs or PMNs
  • tx
    • doxycycline

21

Histologic feature + possible causes?

  • target cell
  • HALT:
    • ​Hemoglobin C disease
    • Asplenia
    • Liver disease
    • Thalassemia

22

Presentation of thalassemias

  • microcytic, hypochromic anemia
  • alpha-thalassemia
    • alpha globin chain is underproduced 
    • severity = ~#/4 genes mutated
    • loss of all four alpha genes ==> hydrops fetalis
  • beta-thalassemia
    • beta globin chain underproduced
    • major = absence
    • minor = underproduction

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