Saengsuda Yuthana
Division of Nuclear Medicine, Department of Radiology Rajavithi Hospital, College of Medicine, Rangsit University, Bangkok, Thailand.
J Med Assoc Thai. 2013 May;96(5):614-24.
Evaluate the success rate of first high dose 100 mCi (3.7 GBq) radioiodine remnant ablation (RRA) in low-risk differentiated thyroid cancer (DTC) patients after surgery and determine factors influencing the success.
Between 1994 and 2011, a retrospective analysis was performed of 166 low-risk DTC patients after surgery (age range 18-76 years, mean age 38 years, 147 women and 19 men) with primary tumor > 1 cm of diameter stage 52 pT1pN0, 85 pT2pN0, 12 pT3pN0, and 17 pTxN0 underwent high dose 100 mCi (3.7 GBq) RRA. Successful RRA was defined as visually undetectable thyroid bed activity or elsewhere on the first follow-up whole body scan (WBS) six to 12 months after RRA and the stimulated thyroglobulin (st-Tg) levels < 2 ng/mL at the same time of follow-up WBS and without interfering thyroglobulin antibodies (TgAb). Additional 1-131 treatment was individualized depending on clinical characteristics with 100 to 150 mCi (3.7-5.5 GBq) 1-131 six to 12 months intervals to achieve no thyroid bed uptake.
Successful RRA was achieved in 122 of the 166 patients (73.5%). Failure by both criteria was seen in nine patients (5.4%). Of the 44 patients with ablation failure, additional I-131 treatment was individualized in 26 patients (59.1%). St-Tg levels at time of ablation and tumor size had significance influences on the success of RRA. The st-Tg levels at time of ablation were 7.5 +/- 11.5 ng/mL (0.1-80.3) in the ablation success group as compared with the ablation failure group of 24.1 +/- 24.9 ng/mL (1.3-97), p-value < 0.001. Patients with ablation failure group had statistical significance of average tumor size greater than patients with ablation success group (3.2 +/- 1.1 and 2.7 +/- 1.1 cm), p-value = 0.012.
The efficacy of first high dose RRA in low-risk DTC after surgery shows comparable rates with those reported in the literature. The two factors influencing ablation success are st-Tg levels at time of ablation and tumor size.
评估低危分化型甲状腺癌（DTC）患者术后首次大剂量100毫居里（3.7吉贝可）放射性碘残留消融（RRA）的成功率，并确定影响成功的因素。
1994年至2011年，对166例术后低危DTC患者（年龄范围18 - 76岁，平均年龄38岁，147例女性和19例男性）进行回顾性分析，这些患者原发肿瘤直径>1厘米，分期为52例pT1pN0、85例pT2pN0、12例pT3pN0和17例pTxN0，均接受了100毫居里（3.7吉贝可）的大剂量RRA。成功的RRA定义为在RRA后6至12个月的首次随访全身扫描（WBS）中，甲状腺床或其他部位未见明显放射性，且在随访WBS时刺激甲状腺球蛋白（st-Tg）水平<2纳克/毫升，同时不存在干扰性甲状腺球蛋白抗体（TgAb）。根据临床特征个体化进行额外的1-131治疗，每隔6至12个月给予100至150毫居里（3.7 - 5.5吉贝可）的1-131，以实现甲状腺床无摄取。
166例患者中有122例（占73.5%）成功进行了RRA。9例患者（占5.4%）两项标准均未达到。在44例消融失败的患者中，26例（占59.1%）接受了个体化的额外I-131治疗。消融时的st-Tg水平和肿瘤大小对RRA的成功有显著影响。消融成功组消融时的st-Tg水平为7.5±11.5纳克/毫升（0.1 - 80.3），而消融失败组为24.1±24.9纳克/毫升（1.3 - 97），p值<0.001。消融失败组患者的平均肿瘤大小大于消融成功组患者，差异具有统计学意义（分别为3.2±1.1厘米和2.7±1.1厘米），p值 = （此处原文有误，推测应为0.012）0.012。
低危DTC患者术后首次大剂量RRA的疗效与文献报道的相近。影响消融成功的两个因素是消融时的st-Tg水平和肿瘤大小。
