Efficacy of Empirical Radioiodine Therapy in Patients with Differentiated Thyroid Cancer and Elevated Serum Thyroglobulin without Evidence of Structural Disease: A Propensity Score Analysis.

We assessed the outcome of administration of empiric radioactive iodine (RAI) therapy to patients with differentiated thyroid cancer (DTC), in a propensity-score-matched cohort of patients with biochemical incomplete response (BIR) and without evidence of structural disease. We retrospectively evaluated 820 DTC patients without distant metastases, who underwent total thyroidectomy followed by RAI therapy, with available BIR at 12 months and follow-up evaluations. The patients were categorized according to the administration of empiric therapy (ET). To account for differences between patients with (n = 119) and without (n = 701) ET, a propensity-score-matched cohort of 119 ET and 119 no-ET patients was created. The need for additional therapy and the occurrence of structural disease were considered as end-points. During a median follow-up of 53 months (range 3-285), 57 events occurred (24% cumulative event rate). The rate of events was significantly higher in the no-ET compared to the ET patients (30% vs. 18% p < 0.001). The multivariate Cox analysis identified age (p < 0.01), pre-therapy Tg (p < 0.05) and empiric RAI therapy (p < 0.01) as predictors of outcome. The Kaplan-Meier analysis found that progression-free survival was lower in no-ET patients compared to the ET group (p < 0.01). In patients with DTC treated with surgery and RAI, and with biochemical incomplete response at the 12-month evaluation, their prognosis seemed to be affected by Tg values and the empiric treatment. The identification of candidates for this approach may improve prognosis.

Tracers for Cardiac Imaging: Targeting the Future of Viable Myocardium.

Ischemic heart disease is the leading cause of mortality worldwide. In this context, myocardial viability is defined as the amount of myocardium that, despite contractile dysfunction, maintains metabolic and electrical function, having the potential for functional enhancement upon revascularization. Recent advances have improved methods to detect myocardial viability. The current paper summarizes the pathophysiological basis of the current methods used to detect myocardial viability in light of the advancements in the development of new radiotracers for cardiac imaging.