Contemporary considerations in adjuvant radioiodine treatment of adults with differentiated thyroid cancer

Differentiated thyroid cancer (DTC) is the most common endocrine malignancy with a growing incidence worldwide. The initial conventional management is surgery, followed by consideration of ¹³¹I treatment that includes three options. These are termed remnant ablation (targeting benign thyroid remnant), adjuvant (targeting presumed microscopic DTC) and known disease (targeting macroscopic DTC) treatments. Some experts mostly rely on clinicopathologic assessment for recurrence risk to select patients for the ¹³¹I treatment. Others, in addition, apply radioiodine imaging to guide their treatment planning, termed theranostics (aka theragnostics or radiotheragnostics). In patients with low-risk DTC, remnant ablation rather than adjuvant treatment is generally recommended and, in this setting, the ATA recommends a low ¹³¹I activity. ¹³¹I adjuvant treatment is universally recommended in patients with high-risk DTC (a primary tumor of any size with gross extrathyroidal extension) and is generally recommended in intermediate-risk DTC (primary tumor >4 cm in diameter, locoregional metastases, microscopic extrathyroidal extension, aggressive histology or vascular invasion). The optimal amount of ¹³¹I activity for adjuvant treatment is controversial, but experts reached a consensus that the ¹³¹I activity should be greater than that for remnant ablation. The main obstacles to establishing timely evidence through randomized clinical trials for ¹³¹I therapy include years-to-decades delay in recurrence and low disease-specific mortality. This mini-review is intended to update oncologists on the most recent clinical, pathologic, laboratory and imaging variables, as well as on the current ¹³¹I therapy-related definitions and management paradigms, which should optimally equip them for individualized patient guidance and treatment.     

Management of Differentiated Thyroid Cancer with Rising Thyroglobulin and Negative Diagnostic Radioiodine Whole Body Scan

BackgroundDifferentiated thyroid carcinoma (DTC) with rising thyroglobulin (Tg) level and negative radioiodine whole body scan results has been observed in follow-up studies. The management of this condition remains controversial. Most studies support blind ¹³¹I treatment while others oppose this approach.AimsTo assess the effects of ¹³¹I therapy for DTC with rising Tg and negative scan results.Selection criteriaRandomised controlled clinical trials, prospective controlled clinical trials and any trials using ¹³¹I treatment or no treatment for Tg-positive and radioiodine-negative disease were included in this review.ResultsDue to the lack of any suitable randomised or prospective controlled trials in this area, it was not possible to undertake a meta-analysis. Eighteen trials were retrieved for further overall assessment. Of 438 patients from 16 studies who were treated empirically with ¹³¹I for Tg-positive and radioiodine-negative disease, 267 (62%) displayed pathological uptake in the thyroid bed, lungs, bone, mediastinum and lymph nodes. In studies in which data were available for serum Tg levels during thyroid-stimulating hormone (TSH) suppression therapy or TSH withdrawal, 188 of 337 patients (56%) showed a decrease in serum Tg. Of 242 patients from five studies who received no specific treatment for Tg-positive and radioiodine-negative disease, 106 (44%) showed spontaneous normalisation and a significant decrease in serum Tg.ConclusionsThe currently available evidence is insufficient for reliable assessment of the potential of ¹³¹I treatment for DTC with elevated Tg and negative scan results. A decrease in serum Tg in 62% of patients with DTC with elevated Tg and negative scan results suggests that ¹³¹I therapy has a therapeutic effect for more than one-half of patients when the Tg level is considered an index of tumour burden. However, considering that 44% of patients with DTC with elevated Tg and negative scan results showed spontaneous normalisation and a significant reduction in serum Tg without any specific treatment, ¹³¹I therapy should be individualised according to clinical characteristics. Other diagnostic techniques are strongly recommended for patients with Tg-positive and radioiodine-negative disease. If these diagnostic results are positive, treatment options such as surgery, external radiotherapy and tumour embolisation should be considered. If diagnostic results are negative, one course of ¹³¹I treatment may be considered in high-risk patients with serum Tg >10 ng/mL after TSH withdrawal or >5 ng/mL under recombinant human TSH stimulation. No further ¹³¹I therapy is indicated for patients with a negative post-therapy radioiodine scan.     

Recombinant human thyrotropin-aided versus thyroid hormone withdrawal-aided radioiodine treatment for differentiated thyroid cancer after total thyroidectomy: A meta-analysis

Background and purpose

We conducted a meta-analysis of randomized controlled trials (RCTs) to compare the effects of recombinant human thyrotropin (rhTSH) and thyroid hormone withdrawal (THW) on thyrotropin stimulation prior to remnant ablation of differentiated thyroid cancer (DTC).

Material and methods

A comprehensive search was conducted for articles discussing rhTSH and THW prior to December 2012. After applying the inclusion criteria, all the available data were summarized to analyze the efficacy of rhTSH and THW for stimulating TSH.

Results

Seven RCTs that involved a total of 1535 patients, were included in the analysis. The ablation rates of the rhTSH group and the THW group were not significantly different (RR = 0.97, 95% CI: 0.94–1.01, p = 0.1). Patients in the rhTSH group had a better quality of life (QoL) than those in the THW group on the day of ablation (RR = 3.92, 95% CI: 3.44–5.40, p < 0.00001). However, there was no difference in the QoL 3 months after ablation (RR = −0.9, 95% CI: −2.20–0.39, p = 0.17). Additionally, there were no significant differences in serum thyroglobulin (Tg) levels measured just before radioiodine remnant ablation (preablation thyroglobulin levels) (RR = −0.14, 95% CI: −0.73–0.45, p = 0.65), or in days of hospital isolation (RR = −10.51, 95% CI: −32.79–11.73, p = 0.35)

Conclusions

Our findings indicate that the administration of rhTSH had resulted in an ablation rate similar to that of THW for DTC patients, but rhTSH provided a better QoL at the time of ablation.     

Can We Discharge Dynamically Risk-Stratified Low-Risk (Excellent Response to Treatment) Thyroid Cancer Patients After 5 Years of Follow-Up?

Aims

The 2014 British Thyroid Association thyroid cancer guidelines recommend lifelong follow-up of thyroid cancer patients. This is probably unnecessary, can cause patient anxiety, is time consuming and places significant demand on National Health Service resources. It has been suggested that low-risk differentiated thyroid cancer (DTC) patients could be discharged to primary care once they are 5 years from diagnosis and treatment. The aim of this study was to investigate the potential safety of this practice.

Radioiodine ablation of post-surgical thyroid remnants after preparation with recombinant human TSH: why, how and when.

AIMS: The use of recombinant human TSH (rhTSH) represents one of the most exciting innovations in the field of differentiated thyroid cancer (DTC) management, but the use of rhTSH for radioiodine post-surgical thyroid remnant ablation is still controversial. The aim of this review is to provide the reader with an analysis of the literature regarding the use of rhTSH for the radioiodine ablation of post-surgical thyroid remnants. METHODS: We performed a literature search of the most relevant papers in the PubMed database. FINDINGS AND CONCLUSIONS: To date, five prospective studies have been published regarding this topic and there is strong evidence of the effectiveness of rhTSH, at least when high doses of 131I are used. Vice-versa, data regarding the outcome of ablation using low doses (30 mCi) are quite different in the studies published. So the problem of the amount of 131I to be administered and the influence of iodine intake is still open. In fact, the results of some studies suggest that 131I uptake could be particularly dependent on iodine intake during the euthyroid state and when low doses of 131I are used. This could be the reason for the reduced radioiodine uptake observed in other studies. However, also when rhTSH stimulation had produced a reduced iodine uptake, this was at least partially compensated for by an increased half-time in thyroid cells. So rhTSH stimulation appears to have pathophysiological bases which all lead to a powerful destructive effect by 131I on thyroid cells. All the data in the literature appear concordant that rhTSH is safe and associated to a good quality of life and the problem of costs appears negligible when compared to the benefits for the patient. In most cases, the use of rhTSH, for radioiodine ablation of post-surgical thyroid remnants can represent the best therapeutic option that we can offer to the patient.     

Evaluation of the surgical completeness after total thyroidectomy for differentiated thyroid carcinoma.

BACKGROUND: To quantify the rate of patients without thyroid remnants, to identify predictive factors for the absence of residual thyroid tissue and to evaluate number, site, size and function of thyroid remnants after total thyroidectomy for differentiated thyroid carcinoma (DTC). METHODS: Thousand one hundred and seventy-eight patients who underwent total thyroidectomy for DTC were evaluated; 343 patients with lymph node or distant metastases and 115 patients with detectable thyroglobulin autoantibodies (TgAb) were excluded. (131)I ablative treatment (RAI) without preliminary diagnostic (131)I whole body scans (DxWBS), and 24-h (131)I quantitative neck uptake (RAIU test) and thyroglobulin (Tg) off L-T4 evaluation were performed in the remaining 720 pts. In 252 patients a 99mTc-pertechnetate pre-operative thyroid scan (99mTc-scan) was used for comparison with (131)I neck scans after RAI to evaluate site of thyroid remnants. Only patients with thyroid remnants were evaluated for successful ablation 6-10 months after RAI. RESULTS: Post-treatment whole body scan (TxWBS) demonstrated lack of thyroid remnants in 50/720 patients and the best predictive factors for the absence of residual thyroid tissue were RAIU <1% and undetectable Tg off L-T4. Thyroid remnants were present in 670/720 patients. In 252 patients with (99m)Tc-scan, 617 sites of functioning thyroid tissue were found: 381 within and 236 outside the thyroid bed. Complete successful ablation was achieved in 610/670 patients with thyroid remnants. CONCLUSIONS: This study confirms that most patients (93.1%) have thyroid remnant after total thyroidectomy for DTC. Most thyroid remnants were contralateral to tumour site and were even observed outside thyroid bed. However, a real total thyroidectomy, demonstrated by negative TxWBS, RAIU <1% and undetectable Tg off L-T4, was achieved in 6.9% of patients.     

Ps-Tg水平在分化型甲状腺癌诊疗中的应用

血清甲状腺球蛋白（thyroglobulin,Tg）是分化型甲状腺癌（differentiated thyroid carcinoma,DTC）术后随访最常用的血清标志物,用于监测DTC复发及转移。然而血清Tg的检测受到多种因素的干扰,如术后残余甲状腺组织、促甲状腺激素（thyroid stimulating hormone,TSH）、甲状腺球蛋白抗体(thyroglobulin antibody,TgAb)、甲状腺过氧化物酶抗体(thyroid peroxidase antibody,TPOAb)等。因此已往认为术后131I治疗前检测激性 Tg（preablative stimulated thyroglobulin,ps-Tg）（TSH>30 μIU/ml刺激状态下的 Tg 水平）水平意义不大。2009年美国ATA指南指出,DTC 患者ps-Tg水平在疾病状态的预测中有一定作用。近年来也有越来越多的研究表明,术前血清 Tg 水平的监测具有重要的临床价值。本文旨在对Tg在甲状腺癌患者疾病监测中的所受到的干扰因素及DTC 术后诊疗过程中的意义进行综述。     

术后分化型甲状腺癌131Ⅰ清甲治疗疗效及影响因素分析

目的：探讨手术后分化型甲状腺癌131Ⅰ清甲治疗的临床疗效及影响因素.方法：对376例分化型甲状腺癌患者行131Ⅰ治疗,并进行2-10年随访,以全身131Ⅰ扫描,甲状腺摄131Ⅰ率、血清TG浓度来评判清甲治疗疗效.结果：376例患者中266例1次131Ⅰ消融成功,1次成功率70.74％.1次消融有效病例333例,有效率为88.56％.消融无效病例43例,无效率11.44％.不同病理类型间一次消融率无统计学差异,不同治疗时间一次消融成功率有统计学差异.结论：甲状腺外科手术＋ 131Ⅰ＋ TSH抑制治疗的综合治疗方法在分化型甲状腺癌的治疗中有重要作用,外科手术方式和手术后到131Ⅰ治疗时间是疗效的重要影响因素.     

Importance of Postoperative Stimulated Thyroglobulin Level at the Time of 131I Ablation Therapy for Differentiated Thyroid Cancer

Background: Serum thyroglobulin detection plays an essential role during the follow-up of thyroid cancerpatients treated with total/near total thyroidectomy and radioiodine ablation. The aim of this retrospective studywas to evaluate the relationship between stimulated serum thyroglobulin (Tg) level at the time of high dose 131Iablation and risk of recurrence, using a three-level classification in patients with differentiated thyroid cancer(DTC) according to the ATA guidelines. Also we investigated the relationship between postoperative stimulatedTg at the time of ablation and DxWBS results at 8-10 months thereafter. Materials and Methods: Patientswith radioiodine accumulation were regarded as scan positive (scan+). If there was no relevant pathologicalradioiodine accumulation or minimal local accumulation in the thyroid bed region, this were regarded as scannegative (scan-) at the time of DxWBS. We classified patients in 3 groups as low, intermediate and high riskgroup for assessment of risk of recurrence according to the revised ATA guidelines. Also, we divided patients into3 groups based on the stimulated serum Tg levels at the time of 131I ablation therapy. Groups 1-3 consisted ofpatients who had Tg levels of ≤2 ng/ml, 2-10 ng/ml, and ≥10 ng/ml, respectively. Results: A total of 221 consecutivepatients were included. In the high risk group according to the ATA guideline, while 45.5% of demonstratedScan(+) Tg(+), 27.3% of patients demonstrated Scan(-) Tg(-); in the intermediate group, the figures were 2.3%and 90.0% while in the low risk group, they were 0.6% and 96.4%. In 9 of 11 patients with metastases (81.8%),stimulated serum Tg level at the time of radioiodine ablation therapy was over 10, however in 1 patient (9.1%)it was <2ng/mL and in one patient it was 2-10ng/mL (p=0.005). Aggressive subtypes of DTC were found in 8 of221 patients and serum Tg levels were ≤2ng/ml in 4 of these 8. Conclusions: We conclude that TSH-stimulatedserum thyroglobulin level at the time of ablation may not determine risk of recurrence. Therefore, DxWBSshould be performed at 8-12 months after ablation therapy.     

Recombinant human thyrotropin (rhTSH) in the follow-up and treatment of patients with thyroid cancer

The follow-up of thyroid cancer is based on the detection of residual and recurrent thyroid carcinoma. This is traditionally done by means of measurements of serum thyroglobulin (Tg) combined with various imaging techniques (131I-whole body scan, ultrasound and other modalities). Tg serum levels and the uptake of 131I on a whole body scan (WBS) depend on TSH stimulation, which in thyroidectomized patients can be obtained either by withdrawal of thyroid hormone treatment (thyroxine) or by administration of exogenous TSH. At present exogenous human TSH is obtained by means of recombinant DNA technology, (recombinant human TSH (rhTSH), Thyrogen). Even if the administration of rhTSH and withdrawal of thyroid hormone are not completely equivalent, the use of rhTSH has already entered the clinical routine (rhTSH Tg test and rhTSH WBS) because with rhTSH the morbidity and discomfort associated with the withdrawal of thyroid hormone can be avoided. At a recent International Consensus Conference on the follow-up of differentiated thyroid carcinoma it was proposed to carry out only Tg measurement after rhTSH stimulation; moreover, it was stated that 131I whole body scan has to be discouraged in patients submitted to radical surgery and radioiodine ablation with no clinical evidence of residual tumor and with undetectable levels of Tg during hormonal suppression of TSH. Similar strategies in this respect tend to eliminate the 131I WBS and propose only the rhTSH Tg test combined with head and neck ultrasound (US). This is still a matter of debate, also because it is not valid for all risk groups and not all patients undergo the same clinical management (radical surgery or not, thyroid ablation with 131I or not). However, the availability of rhTSH will definitely change the management of papillary and follicular thyroid carcinoma, also with regard to iodine treatment. In fact, rhTSH can be used during radioiodine treatment to enhance the 131I uptake by the cancer cells in particular groups of patients. Patients who could benefit from this approach can be divided into three subgroups: 1) patients in whom thyroxine withdrawal may be dangerous because of the effects of long-term TSH stimulation on the tumor mass (brain metastases, vertebral metastases, presence of neurological signs, heart diseases); 2) patients affected by tumors with marked biological aggressiveness and a low iodine uptake (variants of follicular carcinoma, insular carcinoma, tall and columnar cell variants of papillary thyroid carcinoma, Hürthle cell carcinoma); 3) patients with hypothalamic-pituitary alterations. The potential efficiency of rhTSH in radiometabolic treatment is an important issue that has been studied in a limited number of patients, but is worthy of further investigations in large perspective. A recent clinical prospective trial has been proposed by the Thyroid Cancer Study Group of the Istituto Nazionale Tumori and is now ongoing.     

重组人甲状腺刺激激素在131Ⅰ治疗分化型甲状腺癌中的作用研究

目的：比较使用重组人甲状腺刺激激素（rhTSH）和停服甲状腺激素（THW）相结合的方法与单独停服甲状腺激素（THW）在131Ⅰ治疗分化型甲状腺癌（DTC）中的优劣.方法：患者分组：实验组（使用rhTSH与THW相结合法）6例,131Ⅰ治疗前低碘饮食并停服甲状腺素1周后再注射rhTSH.对照组（单独THW法）9例,131Ⅰ治疗前低碘饮食并停服甲状腺素（THW）4周.比较两组停服甲状腺激素前后尿碘浓度;131Ⅰ在血液内半排期;病灶对131Ⅰ的相对摄取比值;DTC患者131Ⅰ一次性治愈率.结果：实验组患者停服甲状腺素1周,尿碘浓度已下降至与对照组无明显差别[（119.67±25.50） μg/L、（107.33±18.49）μg/L,P＞0.05）];实验组患者血液131Ⅰ半排期明显短于对照组[（7.82±1.43）小时、（9.76±1.74）小时,P＜0.05）];实验组与对照组颈部病灶对131Ⅰ的相对摄取比值无明显差别（48.12 ±5.87、46.96±10.11,P＞0.05）;两组一次性治愈率无明显差别（66.7％、55.6％,P＞0.05）.结论：实验组与对照组131Ⅰ治疗效果无明显差别,然而实验组中131Ⅰ在血液中的滞留时间明显短于对照组,提示实验组放射性碘对非靶组织的照射损伤小于对照组,而还不造成患者明显甲状腺功能低下.因此,可以初步认为131Ⅰ治疗前使用rhTSH与THW相结合的方法优于单独THW方法.     

首次131I治疗前刺激性甲状腺球蛋白在预测颈部及远处转移性分化型甲状腺癌的意义

背景与目的：由于受到残余甲状腺等多种因素的影响,刺激性甲状腺球蛋白(stimulated thyroglobulin,sTg)在首次¹³¹I治疗前对分化型甲状腺癌(differentiated thyroid carcinoma,DTC)复发转移的诊断价值尚有争议。该研究旨在探讨sTg在首次¹³¹I治疗前预测DTC患者颈部及远处转移的意义。方法：106例行甲状腺全切术及颈淋巴结清扫术的DTC患者,首次¹³¹I治疗前1天测sTg水平,¹³¹I治疗后5~7 d行¹³¹I全身显像和SPECT/CT断层融合显像。根据是否存在转移,将所有患者分为无转移组(M0)和颈部淋巴结转移组(M1)和远处转移组(M2),比较组间sTg值差异有无统计学意义,并通过ROC曲线及最佳诊断界值点(diagnostic critical point,DCP)评估sTg值预测转移的价值。结果：M0组、M1组和M2组的sTg值的四分位数间距分别为0.47~9.57、12.34~50.86和69.47~462.00 ng/mL。M1组、M2组与M0组的sTg相比差异均有统计学意义(P<0.01和P<0.01)。sTg值的ROC曲线下面积分别为0.872、0.964,DCP分别为23.95和20.93 ng/mL,灵敏度、特异度、准确度分别为68.42%、100%、92.31%和85.71%、100%、95.40%。结论：首次¹³¹I治疗前检测sTg值对DTC转移有重要的预测价值,对远处转移的预测价值更大。     

Implications of mediastinal uptake of 131I with regard to surgery in patients with differentiated thyroid carcinoma

BACKGROUND: Findings of mediastinal uptake of 131I after surgical treatment for differentiated thyroid carcinoma (DTC) are common, especially in young patients. Given the frequency of false-positive findings, a protocol for diagnostic and therapeutic strategies would be useful. With the goal of accurately selecting management strategies, the authors analyzed their data and data found elsewhere in the literature for correlations with the incidence of mediastinal 131I uptake and with treatment for patients exhibiting such 131I uptake. METHODS: All patients with DTC who were treated between 1978 and 2000 at Groningen University Hospital (Groningen, The Netherlands) and who received adjuvant 131I ablation therapy were included in the current analysis, which involved retrospective review of all relevant data. RESULTS: Five hundred four patients with DTC initially underwent total thyroidectomy, with additional 131I ablation performed for 489 of these patients. In 48 of 489 patients (9.8%), 131I uptake was seen in the mediastinum on a posttreatment scan. Analysis of those 48 patients and of cases in the literature demonstrated that serum thyroglobulin levels, risk status, and the presence of thymus on radiologic images were important in the surgical decision-making process. CONCLUSIONS: Mediastinal uptake of 131I on posttreatment scans was found in approximately 10% of patients after total thyroidectomy for DTC. Based on the current data and the data presented in the literature, the authors developed a flow chart for determining appropriate treatment strategies, which included mediastinal dissection for high-risk patients and for patients with serum thyroglobulin levels > 10 ng/mL.     

甲状腺球蛋白和甲状腺球蛋白抗体在分化型甲状腺癌诊治中的应用进展

分化型甲状腺癌（differentiated thyroid cancer，DTC）作为目前发病率上升最快、甲状腺外科最常见的内分泌恶性肿瘤而备受关注。通常选择甲状腺全切或近全切除术，术后配合甲状腺激素替代治疗以及131I消融治疗。甲状腺球蛋白（thyroglobulin，Tg）作为DTC术后随访的血清学标志物，易受到甲状腺球蛋白抗体（thyroglobulin antibody，TgAb）的干扰。本文着重探讨Tg、TgAb在DTC诊治中的意义，以期为研究提供更多的临床依据。      

Should We Routinely Offer a Second Admission for Radioiodine to Patients with High-risk Differentiated Thyroid Cancer?

AimsTo assess whether an elective second admission for radioiodine is useful for patients with high-risk differentiated thyroid cancer (DTC).Materials and methodsA retrospective analysis was carried out on 47 high-risk DTC patients treated with a second admission for radioiodine at our centre during the 2007–2008 period.ResultsIn 21 patients (45%), the surgeon described an incomplete resection. Twenty-six (55%) had surgical macroscopic complete resection, but cancer cells at the margin of excision histologically. Overall, at the second admission for radioiodine, 27 patients (57%) had a normal post-treatment scan and undetectable thyroid-stimulating hormone (TSH) stimulated thyroglobulin. Twenty patients (43%) had raised stimulated thyroglobulin at second admission for radioiodine, of whom only six (13%) had abnormal uptake (>0.1%) on the post-treatment scan.ConclusionsA second admission for radioiodine could have been avoided in most patients. Instead, information from stimulated thyroglobulin and a diagnostic radioiodine scan would have been sufficient to guide further management. This study also provides interesting outcome data on incompletely resected DTC.     

Clinical experience with recombinant human thyrotrophin (rhTSH) in the management of patients with differentiated thyroid cancer

The purpose of this work was to gain clinical experience with and to identify the optimal conditions for the use of recombinant human TSH (rhTSH, commercially available as Thyrogen) in the management of patients with differentiated thyroid cancer (DTC). The study involved 22 patients for a total of 27 administration cycles of rhTSH, for either diagnostic (in 19 instances) and/or therapeutic purposes (in 8 instances). There were 19 patients with papillary cancer (follicular variant in 4, columnar variant in 1) and 3 patients with follicular cancer (1 Hurtle cell variant). All patients had previously undergone total thyroidectomy and 1-5 cycles of 131I-therapy. Thyrogen was administered i.m. according to the suggested protocol: 0.9 mg i.m. on days 1 and 2, radioiodine on day 3. Peak serum TSH levels between 68-237 microIU/mL were observed after rhTSH administration; these were on average 65% higher, on a patient-by-patient basis, than peak serum TSH observed after conventional withdrawal of thyroxine treatment in 19 patients, while in 3 patients they were 28% lower, but still in the potent stimulation range (86-94 microIU/mL). There was general agreement between imaging results obtained under rhTSH stimulation and those obtained on prior occasions during thyroxine withdrawal, although radioiodine uptake was interpreted as less intense following Thyrogen administration. Of 18 patients undergoing rhTSH administration for diagnostic purposes, 11 patients had a negative radioiodine whole-body scan (WBS) and 7 had a positive WBS. Three of the WBS-negative patients were shown to be actually affected by tumor recurrence, respectively by PET with [18F]FDG (in 2 cases) and by post-131I therapy scan. Serum thyroglobulin (hTg) increased to abnormal levels following rhTSH stimulation in 3/7 of the WBS-positive patients as well as in 1/11 WBS-negative patients. In 3/7 WBS-positive as well as in 3/11 WBS-negative patients, serum hTg progressively rose under rhTSH stimulation, yet still remaining below 3 ng/mL. Post-131I therapy scans following Thyrogen administration showed good radioiodine uptake in 7/8 patients, the single unsuccessful case being most likely due to expansion of the iodine pool because of recent use of an iodinated contrast medium. The overall results show the feasibility and practical advantages of employing rhTSH stimulation in the general clinical setting rather than thyroxine withdrawal in the management of DTC patients. Caution should be raised on the interpretation of the serum hTg response to such potent but short-lived TSH stimulation.     

125例复发/持续性分化型甲状腺癌再次手术及其预后影响因素分析

背景与目的：分化型甲状腺癌虽然预后良好,但仍有一部分患者存在复发和（或）转移风险。通过总结再次手术的125例复发/持续性分化型甲状腺的临床资料,探讨其复发/持续原因及部位、再次手术风险及其预后的影响因素。方法：回顾性分析中国医学科学院北京协和医学院北京协和医院2008—2017年同一组医生收治的行手术治疗的复发/持续性性分化型甲状腺癌患者的病历资料。采用2015年美国甲状腺协会动态危险度评估系统对术后随访患者的治疗反应进行评估分级。结果：患者共125例,其中男性26例,女性99例;平均年龄42岁。再次手术原因包括残余腺体复发/持续45例（45/125,36.0%）,中央组淋巴结复发/持续56例（56/125,44.8%）,侧方淋巴结复发/持续58例（58/125,46.4%）。再次手术后并发症包括新发的永久性甲状旁腺功能减退者3例（3/125,2.4%）,喉返神经麻痹者4例（4/125,3.2%）。患者术后平均随访61个月,5年完全缓解率为69.6%（87/125）。多因素分析结果显示,既往手术次数是影响患者预后的独立危险因素（OR=2.948,95% CI：1.125~7.725,P=0.028）。结论：残余腺体及局部淋巴结复发/持续是分化型甲状腺癌持续/复发的主要原因。再次手术风险较高,但有经验的甲状腺专科医生可以将风险控制在较低水平。分化型甲状腺癌复发/持续后再次手术治疗预后良好,既往手术次数是影响患者预后的独立危险因素。     

Salivary gland toxicity after radioiodine therapy for thyroid cancer

AimsSalivary gland toxicity is a common, but not widely appreciated, adverse effect of high-dose radioiodine (¹³¹I). This study was carried out to determine the incidence of symptoms of salivary gland damage after ¹³¹I treatment for differentiated thyroid cancer.Materials and methodsThis was a prospective study of 76 consecutive patients attending thyroid cancer treatment. Symptoms of salivary gland damage (dry mouth, pain and swelling) were assessed during hospital admission and at follow-up visits. Additionally, a retrospective analysis was carried out of patients recorded in our database as having chronic salivary gland swelling after ¹³¹I ablation.ResultsTwenty patients (26%) developed salivary gland toxicity, 11 (15%) had symptoms within the first 48 h, continuing for 12 months in seven of these patients. The onset of toxicity in a further nine (12%) patients with persistent symptoms did not occur until 3 months after therapy. In total, 16 (21%) patients had evidence of chronic toxicity, typically xerostomia, at 12 months. Toxicity was more common after repeated ¹³¹I administration. After searching our thyroid cancer database, we identified an additional five patients to have chronic salivary gland swelling (chronic sialadenitis or pleomorphic adenoma) 20 months to 23 years after ¹³¹I.ConclusionsPain, swelling and dry mouth occurred frequently after ¹³¹I, with some developing symptoms months or years after administration. Early recognition of salivary gland complications may help to reduce morbidity in these patients.