CRNI Antineoplastic and Biologic Therapies 5 — Questions and Answers
Question 1: Which statement best explains the mechanism of action of trastuzumab (Herceptin)?
- It alkylates DNA strands causing cross-linking
- It binds HER2 receptors, inhibiting cell proliferation signaling (Correct answer)
- It inhibits topoisomerase II, preventing DNA unwinding
- It blocks folate metabolism, reducing thymidine synthesis
Correct answer: It binds HER2 receptors, inhibiting cell proliferation signaling
Trastuzumab is a monoclonal antibody that targets HER2 (ErbB2) receptors, blocking downstream proliferative signaling in HER2-overexpressing tumors.
Question 2: A patient develops tumor lysis syndrome 24 hours after starting chemotherapy. Which set of lab findings is characteristic?
- Hypercalcemia, hypokalemia, hypernatremia
- Hyperuricemia, hyperkalemia, hyperphosphatemia, hypocalcemia (Correct answer)
- Hyponatremia, hypoglycemia, elevated BUN
- Hypomagnesemia, hypophosphatemia, metabolic alkalosis
Correct answer: Hyperuricemia, hyperkalemia, hyperphosphatemia, hypocalcemia
Tumor lysis syndrome classically presents with hyperuricemia, hyperkalemia, hyperphosphatemia, and hypocalcemia from rapid release of intracellular contents.
Question 3: When teaching a patient about imatinib (Gleevec) oral therapy, which instruction is most important?
- Take on an empty stomach to improve absorption
- Avoid grapefruit juice as it increases drug levels (Correct answer)
- Limit fluid intake to 1 liter per day
- Do not take with any antacids or dairy products
Correct answer: Avoid grapefruit juice as it increases drug levels
Grapefruit juice inhibits CYP3A4, the enzyme responsible for imatinib metabolism, leading to significantly increased drug plasma levels and toxicity risk.
Question 4: A CRNI is assessing a patient for signs of pegfilgrastim (Neulasta) toxicity. Which complaint warrants immediate evaluation for splenic rupture?
- Mild bone pain in the sternum
- Sudden severe left upper quadrant abdominal pain (Correct answer)
- Generalized fatigue and low-grade fever
- Injection site erythema and swelling
Correct answer: Sudden severe left upper quadrant abdominal pain
Sudden severe left upper quadrant pain in a patient receiving colony-stimulating factors like pegfilgrastim must be evaluated urgently for splenic rupture, a rare but life-threatening complication.
Question 5: Which action by the nurse demonstrates correct handling of oral antineoplastic agents per safe handling guidelines?
- Crushing tablets and mixing into applesauce for easier administration
- Wearing gloves when handling the oral medication and disposing in a hazardous waste container (Correct answer)
- Placing crushed tablets in a standard medication cup without PPE
- Administering at the bedside without additional precautions if the tablet is uncoated
Correct answer: Wearing gloves when handling the oral medication and disposing in a hazardous waste container
Oral antineoplastics require PPE (minimum chemotherapy-rated gloves) during handling and must be discarded as hazardous pharmaceutical waste per NIOSH and ONS guidelines.
Question 6: A patient on nivolumab (Opdivo) presents with worsening shortness of breath and new bilateral infiltrates on chest X-ray. The nurse suspects:
- Pulmonary embolism secondary to hypercoagulability
- Immune-mediated pneumonitis from checkpoint inhibitor therapy (Correct answer)
- Pleural effusion from tumor progression
- Viral pneumonia due to immunosuppression
Correct answer: Immune-mediated pneumonitis from checkpoint inhibitor therapy
Immune checkpoint inhibitors like nivolumab can cause immune-mediated pneumonitis, which may present with dyspnea and bilateral infiltrates and requires immediate evaluation.
Question 7: For a patient receiving oxaliplatin, which nursing intervention is most important to prevent exacerbation of the characteristic acute neurotoxicity?
- Applying warm compresses to the IV site during infusion
- Instructing the patient to avoid cold temperatures and cold beverages (Correct answer)
- Elevating the head of the bed to 30 degrees during infusion
- Administering IV calcium and magnesium before and after infusion
Correct answer: Instructing the patient to avoid cold temperatures and cold beverages
Oxaliplatin causes acute cold-triggered peripheral sensory neuropathy; patients must avoid exposure to cold temperatures and cold liquids to prevent triggering or worsening this neuropathy.
CRNI Antineoplastic and Biologic Therapies 5
Which statement best explains the mechanism of action of trastuzumab (Herceptin)?