- 期刊
【論文摘要】Low-Dose (30 mCi) Radioactive Iodine Therapy in the Patients With Differentiated Thyroid Cancer: VGHKS Experience
摘要
Introduction: The most appropriate dosage of radioactive iodine (RAI) for the patients with differentiated thyroid cancer (DTC) is still a topic of controversy. The choice of RAI dose is usually affected by variable factors. The aim of this study was to investigate (1) practical variations to choose low-dose (30 mCi) RAI therapy (RAIT) and (2) the efficacy of low-dose RAIT. Methods: This was a retrospective analysis of a historical cohort from January 2007 to June 2018 in Kaohsiung Veterans General Hospital (VGHKS). Associated data were collected, including (1) age/sex, pathology, and American Joint Committee on Cancer (AJCC) tumor size, lymph node, metastasis (TNM) stage at initial diagnosis; (2) RAI dosage and times; (3) decision making to choose 30 mCi RAIT. Successful RAIT was defined as stimulated thyroglobulin (sTg) ＜ 2 ng/ml with undetectable serum anti-thyroglobulin antibody (ATA) or absence of obvious uptake on diagnostic whole body scan (DxWBS) or next therapeutic whole body scan (RxWBS) at 4-12 months after first 30 mCi RAIT. Recurrent or persistent disease was defined as non-sTg ＞ 1 ng/ml, positive ATA, sonography or computed tomography according to last follow-up in 2018 (at least 2-year follow-up). Results: Twelve patients received 30 mCi RAIT. Age (33.3%) was the most common factor to affect decision making. Other factors included ATA low risk (25.0%), mental retard (8.3%), uremia under hemodialysis (8.3%), Hashimoto thyroiditis with high ATA and anti-thyroid peroxidase (anti-TPO) antibody (8.3%), weak positive thyroglobulin (Tg)/DxWBS (8.3%), hemoptysis (8.3%), and personal reason (8.3%). Two patients (16.7%) had received high dose (≥ 100 mCi) RAIT after initial surgery and they received 30 mCi RAIT due to recurrent lymph node (LN) metastasis and weak positive Tg/DxWBS. Four patients (33.3%) changed to high-dose RAIT due to recurrent LN metastasis, positive Tg/DxWBS, and multiple metastases. Excluding two patients who receiving RAIT recently, successful RAIT rate was 20% (2/10) and disease-free rate was 70% (7/10). Conclusions: Age and ATA low risk were the most two common factors to affect the choice of low-dose RAIT. Although the rate of successful RAIT was not high at 4-12 months after first 30 mCi RAIT, but high disease-free rate was noted after additional low- or high-dose RAIT.