Comparison of pretreatment and post-treatment whole body scan results (WBS) with I-131 in 94 patients with differentiated Thyroid cancer (DTC) [Persian]

Document Type : Original Article

Authors

Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran

Abstract

Discrepancy between pre & post treatment WBSs (Low dose & high dose, respectively) is reported. The aim of this study was determination the post-treatment WBS role in the diagnosis of lesions not identified by the pretreatment one. In this study 94 patients (pts) with DTC were evaluated. The results of pre & post treatment WBSs were compared. Overall, 25.6% of pts revealed more positive lisions in comparison with their pretreatment WBS. The increase in positive results in pts<35 yr was 36% and in pts>35yr was 25%. In males and females, the increased values were 33.3% & 23.58% respectively. In all types DTC post-treatment WBS revealed more involvement. In cases limited to thyroid, with capsular invasion and with lymph node involvement the increased values were: 20.5%, 28.5% & 35.7%, respectively. In cases with TSH<30m U/L, 53.8% & in cases with TSH>30 mU/L, 22.2% more positive lesions were observed. Pts with Htg<10 ng/ml & >10 ng/ml, post-treatment WBS revealed more lesions in 28% & 21.8%, respectively. Conclusion: Post-treatment WBS improves rate of detection of thyroid cancer lesions. In our study this was especially true in cases with TSH<30 mU/l & Pts younger than 35yr.

Main Subjects