Question

Why should a patient avoid physical activity before a PET scan?

A. To prevent the Warburg effect
B. To accelerate glucose uptake by tumor cells
C. To prevent the absorption of the radioactive tracer by healthy tissues
D. To promote fermentation in healthy tissues E. All of the above

Answer 1

Avoiding physical activity before a PET scan helps ensure that the muscles do not absorb the radioactive glucose analog, allowing it to better target tissues with abnormal metabolism.

Step-by-step explanation:

Patients are recommended to avoid physical activity before a positron emission tomography (PET) scan to prevent the muscles from using up the radioactive tracer, which is a glucose analog like fludeoxyglucose (FDG). Since the muscles would absorb the tracer, it could result in a suboptimal distribution of the tracer where it's needed most—in the tissues with abnormal metabolic activity, such as cancer cells. The right answer is to prevent the absorption of the radioactive tracer by healthy tissues.