Ju Dal Lae, Park Young Joo, Paik Hee-Young, Song YoonJu
Department of Food Service and Nutrition Care, Seoul National University Hospital, Seoul 03080, Korea. ; Department of Food and Nutrition, Seoul National University, Seoul 08826, Korea.
Department of Internal Medicine, Seoul National University College of Medicine, Seoul 03080, Korea.
Clin Nutr Res. 2015 Oct;4(4):267-71. doi: 10.7762/cnr.2015.4.4.267. Epub 2015 Oct 31.
To improve the efficacy of radioactive iodine (RAI) therapy for differentiated thyroid cancer patients, a low-iodine diet (LID) prior to the therapy is recommended. In iodine-rich areas such as Korea, however, a strict LID is very difficult to maintain. We experienced the cases of three patients showing low adherence to the LID before initial RAI therapy, and analyzed the main food source supplying iodine during the LID, and examined the influence of the poorly maintained LID on the efficacy of RAI therapy. The dietary intake during the LID periods were assessed using three-day dietary records and remnant thyroid activity after the second RAI administration was also evaluated. All patients' mean daily iodine intake during two-week LID periods exceeded the 100 µg guideline set by the Korean Thyroid Association (median 110.9 µg, ranges 100.4-117.0 µg). Although the typical food sources of iodine intake are seaweeds in Korea, salted vegetables were the main contributor to the patients' iodine intake during the LID periods. Remnant thyroid activity was shown on a follow-up scan in all of 3 patients suggesting low efficacy of RAI therapy. In summary, the patients with low adherence to the LID guideline showed unsuccessful remnant ablation, and the main food source of iodine was salted vegetables. Further studies are necessary to examine the relationship between adherence of the LID and RAI efficacy according to dietary iodine intake levels, as well as food sources that cause low adherence to the LID. These data can then be used to develop more practical LID guidelines.
为提高放射性碘（RAI）治疗分化型甲状腺癌患者的疗效，建议在治疗前采用低碘饮食（LID）。然而，在韩国等碘丰富地区，严格的低碘饮食很难维持。我们遇到了3例在首次RAI治疗前对低碘饮食依从性差的患者，分析了低碘饮食期间供应碘的主要食物来源，并研究了低碘饮食维持不佳对RAI治疗疗效的影响。使用三天饮食记录评估低碘饮食期间的饮食摄入量，并评估第二次RAI给药后的残余甲状腺活性。所有患者在两周低碘饮食期间的平均每日碘摄入量超过了韩国甲状腺协会设定的100μg指南（中位数110.9μg，范围100.4 - 117.0μg）。虽然在韩国，碘摄入的典型食物来源是海藻，但腌制蔬菜是患者在低碘饮食期间碘摄入的主要来源。3例患者在随访扫描中均显示有残余甲状腺活性，提示RAI治疗效果不佳。总之，对低碘饮食指南依从性差的患者残余消融未成功，碘的主要食物来源是腌制蔬菜。有必要进一步研究根据饮食碘摄入水平以及导致低碘饮食依从性差的食物来源，低碘饮食的依从性与RAI疗效之间的关系。这些数据随后可用于制定更实用的低碘饮食指南。
