Which of the following organs shows normal biodistribution for Tc sestamibi?

• A. Pancreas
• B. Large intestines
• C. Thyroid
• D. Skin

Answer: (C)

The organ that shows normal biodistribution for Tc sestamibi is the thyroid. Tc sestamibi is a radiopharmaceutical commonly used in myocardial perfusion imaging and is known for its cardiac uptake. However, it also has specificity for the thyroid gland due to the presence of mitochondrial uptake mechanisms. As a result, the thyroid gland demonstrates a typical biodistribution pattern when Tc sestamibi is administered, allowing for effective imaging of thyroid function and pathology.

In contrast, the pancreas, large intestines, and skin do not exhibit significant uptake of Tc sestamibi, which is why they are not considered normal biodistribution sites for this radiopharmaceutical. This specificity for the thyroid helps healthcare professionals in identifying potential abnormalities within the gland, making it an important aspect of diagnostic imaging in nuclear medicine.