Determining patient selection tool and response predictor for outpatient 30 mCi radioiodine ablation dose in non-metastatic differentiated thyroid carcinoma: a Japanese perspective.

This study evaluated factors to find response predictor and determinant for the suitable patients. The retrospective study reviewed 47 eligible non-metastatic papillary DTC patients whose had first 30 mCi RAI ablation after total thyroidectomy. Age, gender, clinical stage, risk category, and pre-ablation serum thyroglobulin (Tg) level were among covariates analyzed to determine the patient selection factors; while the thyroid bed uptake on initial whole body scan (WBS) was later also included in determining RAI ablation response. Thirteen (28%) patients had a low risk (T1-2) while 23 (49%) and 11 (23%) had an intermediate (T3) or high risk (T4), respectively. Twenty-five patients were responders, and 22 were non-responders. All factors were similar between responders and non-responders except pre-ablation serum Tg level (p < 0.001). In multivariate analysis, pre-ablation serum Tg level was the only significant factor for both patient selection (odd ratio (OR) = 1.52, 95% confidence interval (CI) = 1.13-2.06) and response predictor (OR = 1.48; 95% CI = 1.12-1.95). With the cut-off of 5.4 ng/mL, pre-ablation serum Tg level predicts RAI ablation response with 92% specificity and 73% sensitivity. Pre-ablation serum Tg level may help patient selection and predict the response to outpatient 30 mCi RAI ablation among post total thyroidectomy non-metastatic DTC patients. PMID: 29343651 [PubMed - as supplied by publisher]
Source: Endocrine Journal - Category: Endocrinology Tags: Endocr J Source Type: research