RT Journal Article
SR Electronic
T1 Immediate change of serum thyroglobulin level after radioiodine treatment can be an early predictor for therapy response
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 2107
OP 2107
VO 53
IS supplement 1
A1 Yong-il Kim
A1 Jin chul Paeng
A1 Hyun-Yeol Nam
A1 In Kook Chun
A1 Hongyoon Choi
A1 Keon Kang
A1 June-Key Chung
YR 2012
UL http://jnm.snmjournals.org/content/53/supplement_1/2107.abstract
AB 2107 Objectives The purpose of this study is to evaluate whether immediate change of serum thyroglobulin (Tg) level after radioiodine therapy can be a predictive factor for ablation of residual thyroid or metastatic lesion. Methods 29 patients performed radioiodine therapy, and measured serum Tg level immediately (post 4 days) after (RAI) therapy and following treatment (after 6-12 months). Thyroid function test parameters, Tg and TgAb were measured by radioimmunoassay kits. rTg (Immediate Tg/1st time stimulation Tg), dTg (Immediate Tg - 1st time stimulation Tg), rTgAb (Immediate TgAb/1st time stimulation TgAb) and dTgAb (Immediate TgAb - 1st time stimulation TgAb) were calculated. I-131 whole body scan parameters were rUptake (1-(2nd time therapy uptake ratio/1st time therapy uptake ratio)) and dUptake (1st time therapy uptake ratio - 2nd time therapy uptake ratio). Uptake (Lesion ROI uptake/Brain ROI uptake) was calculated according to geometric average of lesion in anterior and posterior images of I-131 whole body scan. Results Positive correlation between rTg and rUptake was checked by Pearson’s correlation (correlation coefficient = 0.382, P=0.041). In subgroup analysis, rTg more than 1.5 reveals significantly high rUptake and dUptake (rUptake: 0.74±0.25 vs. 0.45±0.31, P=0.01). Moreover, rUptake more than 0.7 revealed high rTg with significance (rTg: 8.80±9.50 vs. 1.31±0.81, P=0.003). Conclusions High ratio between immediate Tg and 1st time stimulation Tg reflects high ablation rate of residual or metastatic lesion after radioiodine therapy