Oncology Flashcards
What is the most common malignancy that causes hypercalcemia?
Lymphoma
What is the most common clinical manifestation of hypercalcemia?
- PU/PD
- Calcium inhibits vasopressin receptors in kidney and prevents free water absorption, creating a nephrogenic DI
- The hypercalcemic pt is often dehydrated due to inability to concentrate urine; dehydrated pts have a decreased GFR which further exacerbates hypercalcemia
Hypercalcemia primarily affects what 4 body systems?
- Renal
- GI
- Neuro
- Cardiovascular
What is calcitriol?
- The active product of Vit D metabolism
- Leads to increased GI absorption of Ca and increased release of Ca from bone
What drugs can be used to promote Ca excretion?
- Furosemide (Na utilizes the same pump as Ca)
- Glucocorticoids
- Bisphosphonates (inhibit bone osteoclast activity)
- NaHCO3 (correction of acidosis will result in increased binding of Ca to albumin)
- Calcitonin (inhibits osteoclasts)
- EDTA (chelates Ca)
- Mithramycin (cytotoxic to osteoclasts)
What complication can arise from L-asparaginase administration?
Lspar is a protein so a reaction is more likely after 1st use
What complications can arise from doxorubicin administration?
- Head shaking, salivation
- Reactions secondary to degranulation of mast cells
- Cardiotoxic
What is the antidote that should be instilled in the case of extravasation of doxorubicin?
- Vesicant
- Dexrazoxane or DMSO
What is the antidote that should be instilled in the case of extravasation of vincristine/vinblastine?
- Vesicants
- Hyaluronidase
What is the antidote that should be instilled in the case of extravasation of mechlorethamine?
- Severe vesicant
- Thiosulfate
What is the antidote that should be instilled in the case of extravasation of cisplatin?
- Irritant
- Thiosulfate
What is the nadir?
The point at which chemo has its greatest effects on the number of circulating neutrophils and they are at their lowest population
How long after chemo administration does neutropenia commonly occur?
5-10 days
Neutropenia grading scale in chemo
- Grade 1 = normal to 1500/uL
- Grade 2 = 1500 - 1000/uL
- Grade 3 = 1000 - 500/uL
- Grade 4 = <500/uL
Which chemo drug is most commonly associated with vomiting?
Cisplatin
What drug blocks both the CRTZ and vomiting center?
Butorphanol
What chemo drug is most commonly associated with anorexia?
Doxorubicin
What chemo drug causes paralytic ileus?
Vincristine
Tachyarrhythmia is an early sign of toxicity of which chemo drug?
Doxorubicin
Which chemo drug can cause a sterile hemorrhagic cystitis?
Cyclophosphamide
Which chemo drug is nephrotoxic?
Cisplatin
Which chemo drug is hepatotoxic?
CCNU/Lomustine
Cardiac HSA are almost always found on the ___?
Right atrium
Female dogs are more at risk than male dogs for which type of cancer?
TCC
What is tumor lysis syndrome?
- Rupture of the cancer cells which then releases their intracellular contents into tissues and blood. The rapid release of byproducts overwhelms the body’s ability to clear waste
- Ca, nucleic acids, K, phos
- Tumor cells can contain up to 4x normal quantity of Phos due to their increased need for ATP
- The hyperphos causes hypoCa
- The hyperK + hypoCa can lead to life threatening arrhythmias
- AKI results from Ca + phos precipitation
- English bulldogs and dalmations more at risk
What is paraneoplastic syndrome (PNS)?
- Any systemic illness that is induced by neoplasia but occurs in a body system from from, and unrelated to, the primary tumor
- Most common PNS in dogs are caused by production of hormones (insulin, calcitonin, PTH etc) that leads to endocrine-like effects
Which cancer is a common cause of PNS?
Lymphoma
What are the most common chemistry abnormalities from PNS?
- Hypercalcemia and hypoglycemia
What is the most common metabolic emergency seen in veterinary cancer patients?
Hypercalcemia
