Circlet Sign: Urinary Contamination on 177 Lu-DOTATATE Posttherapy Imaging.

Peptide receptor radionuclide therapy has revolutionized the management of somatostatin receptor-positive metastatic neuroendocrine tumours. Treating nuclear medicine physicians must be aware of the radiation hazards posed by radioactive contamination and the imaging fallacies attributable to radioactive contamination on posttherapy planar imaging. The image fallacies, if not properly looked upon, upstage the disease. Also, radioactive contamination with body fluids on any external structure in close contact with the patients poses a prolonged radiation hazard. The authors in this present research demonstrate image fallacy due to radioactive urinary contamination on 177 Lu-DOTATATE posttherapy imaging.