Treatment room length-of-stay and patient throughput with radioiodine thyroid remnant ablation in differentiated thyroid cancer: comparison of thyroid-stimulating hormone stimulation methods

Objectives We sought to empirically compare treatment room length-of-stay and patient throughput for recombinant human thyroid-stimulating hormone (rhTSH)-aided thyroid remnant ablation with thyroid hormone withdrawal (THW)-aided ablation in patients with differentiated thyroid carcinoma (DTC). Methods We retrospectively reviewed charts of all eligible (near) totally thyroidectomized patients with DTC undergoing ablation and 1-year ablation success evaluation at our tertiary referral centre from January 2003 to February 2009 (N = 274). M1 disease caused exclusion unless discovered by a postablation scan or present when rhTSH was the only tolerable stimulation method. We extracted data on the length-of-stay, defined as the time between treatment room admission and discharge, and patient throughput, defined as patients ablated per treatment room per week. The treatment room discharge criterion was a whole-body dose rate of less than 60 mu Sv/h at 50 cm. Results The treatment groups (rhTSH, n = 187; THW, n = 87) had mostly statistically similar characteristics, but differed in primary tumour status distribution. In addition, at ablation, the rhTSH patients had a greater prevalence of prior diagnostic scintigraphy, higher mean serum TSH, and shorter interval since surgery, and received a 5.6% larger mean ablation activity. On average, rhTSH patients had a significantly lower peak whole-body dose rate (57.1 vs. 83.4 mu Sv/h at 50 cm; P < 0.0001) and a significantly shorter treatment room stay than did the THW patients (1.41 vs. 2.02 days; P < 0.001). rhTSH use allowed significantly more patients to be ablated per room per week (2.7 vs. 1.2; P < 0.001). Conclusion Relative to THW, rhTSH use to aid ablation reduced mean treatment room length-of-stay by almost one-third and more than doubled the average weekly patient throughput, both of which were significant differences. Nucl Med Commun 32: 840-846 (C) 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins. Nuclear Medicine Communications 2011, 32: 840-846