To Use or Not to Use 131I in Thyroid Cancer.

PURPOSE: The purpose of the following commentary is to discuss recent controversies in the use of radioactive iodine for differentiated thyroid cancer (DTC). METHODS: R. M. Tuttle (Thyroid 2010; 20:257-263), at Memorial Sloan Kettering Cancer Center, has enumerated the well-accepted goals of radioactive iodine therapy (RAIT) in DTC: (1) ablate residual thyroid to facilitate future surveillance, (2) "adjuvant therapy" for residual radioactive iodine-avid disease, and (3) a post-RAIT scan may reveal unknown local and/or distant metastases. Using these goals as a guide, the authors have critically reviewed a recent movement to decrease the use of RAIT in DTC that is being advocated by some investigators. RESULTS: As a result, a recent article has highlighted this new treatment philosophy. A 2017 publication in the Journal of Clinical Oncology (Molenaar et al, 2017 0:JCO.2017.75.0232) recommends that RAIT not be used in low- or intermediate-risk DTC. In this article, the authors claim that the RAIT risks in DTC, particularly leukemia, outweigh its potential benefits. This change, if adopted, in our opinion will have profound deleterious consequences on patient outcomes. We also have identified a major problem with the article of Molenaar et al. The authors use the American Thyroid Association's criteria for staging thyroid cancer. In our opinion, this method of staging is severely flawed. We also quantitatively compare the article's alleged risk of RAIT-induced leukemia with the benefits of RAIT for DTC. CONCLUSIONS: In summary, this matter must be debated before eliminating RAIT in low- or intermediate-risk DTC. If RAIT is eliminated for these patients, many such patients will no longer benefit from the RAIT goals listed by R. M. Tuttle, including the critical advantage of potentially improved overall and event-free survival.

Current controversies in the initial post-surgical radioactive iodine therapy for thyroid cancer: a narrative review.

Differentiated thyroid cancer (DTC) is the most common endocrine malignancy and the fifth most common cancer in women. DTC therapy requires a multimodal approach, including surgery, which is beyond the scope of this paper. However, for over 50 years, the post-operative management of the DTC post-thyroidectomy patient has included radioactive iodine (RAI) ablation and/or therapy. Before 2000, a typical RAI post-operative dose recommendation was 100 mCi for remnant ablation, 150 mCi for locoregional nodal disease, and 175-200 mCi for distant metastases. Recent recommendations have been made to decrease the dose in order to limit the perceived adverse effects of RAI including salivary gland dysfunction and inducing secondary primary malignancies. A significant controversy has thus arisen regarding the use of RAI, particularly in the management of the low-risk DTC patient. This debate includes the definition of the low-risk patient, RAI dose selection, and whether or not RAI is needed in all patients. To allow the reader to form an opinion regarding post-operative RAI therapy in DTC, a literature review of the risks and benefits is presented.

The "hot nose" sign on brain death nuclear scintigraphy: where does the flow really go?

Nuclear scintigraphy has been used in patients with brain death since the 1970s. Many studies report a "hot nose" sign as predictive of brain death and lack of cerebral flow. Current nuclear medicine textbooks state that increased flow to the nose occurs secondary to occlusion of the internal carotid artery with flow rerouted to the nose via the external carotid artery. This explanation has been provided for decades assuming that the blood flow is actually increased to the nose. We performed a study to determine whether flow is really seen in the nose when a hot nose sign is present.