甲状腺乳头状癌患者术后首次131I治疗后辐射剂量率的影响因素及出院时间的探讨

目的 探讨甲状腺乳头状癌(PTC)患者术后首次131I治疗后影响辐射剂量率降低的相关因素,并预估其住院隔离时间。方法 选取2015年5月至2018年11月于南方医科大学珠江医院住院并首次行131I治疗的PTC患者167例,其中男性43例、女性124例,年龄(37.14± 12.00)岁。将所有患者按治疗剂量分为高剂量组(63例)和低剂量组(104例),于治疗后24、48、72、96 h时测量距离患者1 m处的辐射剂量率,将治疗后患者体内滞留131I活度为400 MBq时的时间点定为出院时间。采用多重线性回归方法分析影响辐射剂量率降低的相关因素。组间比较采用两独立样本非参数检验或两独立样本t检验。结果 PTC患者首次行131I治疗后的辐射剂量率随时间推移迅速下降,高剂量组治疗后的24、48 h辐射剂量率[(70.62±34.45)、15.64 μSv/h]明显高于低剂量组[(11.27±5.13)、2.03 μSv/h],且差异均有统计学意义(t=-13.581、-7.952,均P <0.01)。81.0%(51/63)和90.5%(57/63)的高剂量组患者分别可在治疗48 h和72 h后出院,99%(103/104)的低剂量组患者可在治疗24 h后出院。多重线性回归分析显示,131I剂量和2 h摄碘率对高剂量组24 h辐射剂量率的影响有统计学意义(F=9.23,复相关系数R2=0.212,P<0.01),高剂量组24 h辐射剂量率与2 h摄碘率和131I剂量呈正相关;性别、24 h摄碘率和残甲法3对高剂量组48 h辐射剂量率的影响有统计学意义(F=34.45,复相关系数R2=0.622,P<0.01),48 h辐射剂量率与24 h摄碘率和残留甲状腺体积呈正相关,与性别呈负相关;131I剂量和24 h饮水量对低剂量组24 h辐射剂量率的影响有统计学意义(F=12.76,复相关系数R2=0.186 ,P<0.01),低剂量组24 h辐射剂量率与131I剂量呈正相关,与24 h饮水量呈负相关。结论 PTC术后患者首次131I治疗24 h后,影响其辐射剂量率降低的主要因素是服用131I的剂量,而48 h后的主要影响因素是24 h甲状腺摄碘率、残留甲状腺体积和性别。低剂量组和高剂量组平均住院时间分别为1 d和2 d左右。

Factors of radiation dose rates and hospitalization days for papillary thyroid cancer patients with after first 131I therapy

Objective To explore the related factors affecting the reduction of radiation dose rate and to estimate the hospitalization days in papillary thyroid cancer(PTC)patients with postoperative after first 131I therapy.Methods A total of 167 patients with PTC were hospitalized and treated with iodine-131 from May 2015 to November 2018 at Zhujiang Hospital,Southern Medical University.The patients were divided into the high-dose group(63 cases)and the low dose-group(104 cases).The radiation dose rates of the two groups of patients at different time points were measured at a distance of 1 m,the required hospitalization isolation time was analyzed,and the factors related to the reduction in radiation dose rate were analyzed by using multiple linear regression method.Two independent samples nonparametric test and t-test were used to compare the differences between groups.Results After iodine-131 treatment for the first time,the radiation dose rate of the patients with PTC decreased exponentially with time,and the radiation dose rates of the high-dose group[(70.62±34.45),15.64μSv/h]at 24 h and 48 h after iodine-131 treatment were significantly higher than those of the low-dose group[(11.27±5.13),2.03μSv/h](t=?13.581,?7.952,both P<0.01).Approximately 81.0%(51/63)and 90.5%(57/63)of the high-dose group were discharged after iodine-131 treatment for 48 h and 72 h,respectively.By contrast,99%(103/104)of the low-dose group was discharged after iodine-131 treatment for 24 h.According to multiple linear regression analysis,the effects of iodine-131 dose,iodine uptake rate at 2 h on radiation dose rate at 24 h in the high dose group were statistically significant(F=9.23,complex correlation coefficient R2=0.212,P<0.01),and both iodine-131 dose and iodine uptake rate at 2 h had positive correlation with 24 h radiation dose rate.The effects of gender,iodine uptake rate at 24 h and residual thyroid volume(method 3)on radiation dose rate at 48 h in the high-dose group were statistically significant(F=34.45,complex correlation coefficient R2=0.622,P<0.01),moreover the radiation dose rate at 48 h was positively correlated with iodine uptake rate at 24 h and residual thyroid volume,and negatively correlated with gender.The effects of iodine-131 dose and drinking water amount at 24 h on the radiation dose rate at 24 h in the low-dose group were statistically significant(F=12.76,complex correlation coefficient R2=0.186,P<0.01),furthermore the radiation dose rate at 24 h in the low-dose group was positively correlated with iodine-131 dose,and negatively correlated with drinking water amount at 24 h.Conclusions After the first iodine-131 treatment for 24 h,the main factors influencing the reduction in the radiation dose rate of patients with PTC were the dose of iodine-131.The main factors influencing the reduction in radiation dose rate after 48 h were the iodine uptake rate of the thyroid at 24 h,the volume of the residual thyroid gland,and the gender of the patient.The mean hospitalization time in low dose group and high dose group was about 1 day and 2 days respectively.