Which nuclear medicine study with CT scan is used to stage thyroid cancer?

Which nuclear medicine study with CT scan is used to stage thyroid cancer?

• A. Scintigraphy
• B. SPECT
• C. PET
• D. Ultrasound

Answer: (C)

Staging thyroid cancer often requires imaging that shows both where disease is and how active it is metabolically. PET-CT does this by using a tracer (like 18F-FDG) that highlights areas with increased glucose metabolism, a hallmark of cancer, and combines it with CT to pinpoint the exact anatomical location. This makes it especially useful for detecting metastases or recurrent disease that may not take up radioactive iodine, which is a limitation of traditional iodine scans. While iodine-based scintigraphy can map functioning thyroid tissue and SPECT/CT can localize lesions, they focus on iodine-avid tissue and may miss non-avid metastases. Ultrasound excels at evaluating the thyroid and regional neck nodes but cannot assess distant disease. For comprehensive staging in many thyroid cancer cases, PET-CT provides the most informative, integrated metabolic and anatomic view.

Staging thyroid cancer often requires imaging that shows both where disease is and how active it is metabolically. PET-CT does this by using a tracer (like 18F-FDG) that highlights areas with increased glucose metabolism, a hallmark of cancer, and combines it with CT to pinpoint the exact anatomical location. This makes it especially useful for detecting metastases or recurrent disease that may not take up radioactive iodine, which is a limitation of traditional iodine scans.

While iodine-based scintigraphy can map functioning thyroid tissue and SPECT/CT can localize lesions, they focus on iodine-avid tissue and may miss non-avid metastases. Ultrasound excels at evaluating the thyroid and regional neck nodes but cannot assess distant disease. For comprehensive staging in many thyroid cancer cases, PET-CT provides the most informative, integrated metabolic and anatomic view.