Why is a MUGA scan performed prior to cycle 3 in regimens including pertuzumab?

• A. To assess left ventricular ejection fraction (LVEF)
• B. To evaluate liver enzymes
• C. To measure serum creatinine
• D. To assess tumor response

Answer: (A)

Cardiac safety is the focus when using pertuzumab because this class of therapy can affect heart muscle function and reduce how well the heart pumps. A MUGA scan measures the left ventricular ejection fraction, the percent of blood the left ventricle ejects with each beat, giving an objective snapshot of heart function. Performing it before the third cycle provides a baseline and helps detect any early decline in function, allowing treatment decisions (like delaying or adjusting therapy) to protect the patient. The other options don’t fit because liver enzymes, kidney function, and tumor response are not what a MUGA scan evaluates.