Physiologic Thymic Uptake as a Reason of False-Positive Uptake on Radioiodine Whole-Body Scintigraphy

False-positive uptake on radioiodine whole-body scintigraphy: physiologic and pathologic variants unrelated to thyroid cancer.

Radioiodine whole-body scintigraphy (WBS), which takes advantage of the high avidity of radioiodine in the functioning thyroid tissues, has been used for detection of differentiated thyroid cancer. Radioiodine is a sensitive marker for detection of thyroid cancer; however, radioiodine uptake is not specific for thyroid tissue. It can also be seen in healthy tissue, including thymus, breast, liv...

Physiologic and False Positive Pathologic Uptakes on Radioiodine Whole Body Scan

A radioiodine whole body scan relies on the fact that differentiated thyroid cancer is more efficient at trapping circulating radioiodine than any other tissues.(Hyer, Newbold et al. 2010) Therefore, when I-131 is administered it accumulates in the thyroid cancer tissues and a radioiodine whole body scan plays an important role in the management of patients with differentiated thyroid cancer. U...

Unusual false-positive results of whole-body 131I scintigraphy: Four different case scenarios

Post-treatment or diagnostic whole-body radioiodine scintigraphy is widely used to assess the residual, recurrence, or metastases of differentiated thyroid carcinoma because of the high sensitivity and accuracy that this assessment provides. While bearing in mind all the diagnostic potential of this test, we have to consider its’ potential pitfalls, as well. Herein, we present 4 patients with d...

Nasoalveolar cyst as a cause of false positive result in post-therapy 131I whole body scintigraphy.

We present the case of a 72-year-old male who underwent thyroidectomy for encapsulated follicular carcinoma (3.5 cm×3 cm) in the left thyroid lobe andwas referred to the Department of Nuclear Medicine for ablationof thyroid remnants.Onadministrationof 131I (3700MBq) theTSHvaluewas63.8 IU/ml, thyroglobulin0.4ng/ml and antithyroglobulin antibodies 25.70U/ml. In the whole body scan (WBS) performed...

False-positive orbital uptake on (131)I scintigraphy due to ocular prothesis.