A client with HER2-positive breast cancer is starting trastu… | MyMerci
Medical EmergenciesPA
Question
A client with HER2-positive breast cancer is starting trastuzumab. Which baseline and follow-up assessment is essential?
1Baseline CBC with differential and weekly monitoring — trastuzumab commonly causes neutropenia, increasing the risk of life-threatening infections during therapy
2Baseline liver function tests and monthly thereafter — trastuzumab is hepatotoxic, particularly in patients with liver metastases, requiring routine surveillance
3Baseline LVEF (echo or MUGA) and serial LVEF every 3 months — trastuzumab causes reversible cardiotoxicity, magnified by anthracycline exposure✓ Correct answer
4Baseline PFTs and serial every 3 months — trastuzumab may cause interstitial pneumonitis, requiring early detection to prevent fibrosis
Explanation
Correct (2): Trastuzumab (anti-HER2) causes reversible cardiomyopathy, especially after/with anthracyclines. Baseline + every 3-month LVEF monitoring. Hold for ≥16% absolute LVEF decline or drop below institutional threshold. Often reversible upon discontinuation, unlike anthracycline. (1,3,4) Unrelated.