CSP Clinical Management: Oncology 2

Question 1

A patient stable on imatinib for CML is started on rifampin for tuberculosis. What is the expected effect on imatinib?

Accepted Answer

Decreased imatinib exposure and possible loss of response

Answer

Rifampin strongly induces CYP3A4, which metabolizes imatinib, lowering its plasma concentrations.

Question 2

Which pharmacogenomic test identifies patients at increased risk of severe or fatal toxicity from capecitabine?

Accepted Answer

DPYD genotyping

Answer

DPYD variants reduce dihydropyrimidine dehydrogenase activity, impairing fluoropyrimidine clearance and causing severe toxicity.

Question 3

Why is abiraterone acetate co-administered with prednisone in metastatic prostate cancer?

Accepted Answer

To reduce mineralocorticoid excess such as hypokalemia, hypertension, and fluid retention

Answer

CYP17 inhibition raises ACTH and mineralocorticoid levels, and prednisone suppresses this compensatory effect.

Question 4

Which adverse effect of ibrutinib warrants periodic cardiac monitoring and patient counseling?

Accepted Answer

Atrial fibrillation

Answer

Ibrutinib is associated with atrial fibrillation and bleeding, so palpitations should be reported and anticoagulant use carefully assessed.

Question 5

Osimertinib is preferred in EGFR-mutated NSCLC partly because it is active against which resistance mutation?

Accepted Answer

EGFR T790M

Answer

Osimertinib is a third-generation EGFR TKI that inhibits both sensitizing EGFR mutations and the T790M resistance mutation.

CSP - Certified Specialty Pharmacist Practice Test