A case of stunning of lung and bone metastases of papillary thyroid cancer after a therapeutic dose (3.7 GBq) of131I and review of the literature: implications for sequential treatments

2022 ETA Consensus Statement: What are the indications for post-surgical radioiodine therapy in differentiated thyroid cancer?

Modern use of post-operative radioactive iodine (RAI) treatment for differentiated thyroid cancer (DTC) should be implemented in line with patients' risk stratification. Although beneficial effects of radioiodine are undisputed in high-risk patients, controversy remains in intermediate-risk and some low-risk patients. Since the last consensus on post-surgical use of RAI in DTC patients, new retrospective data and results of prospective randomized trials have been published, which have allowed the development of a new European Thyroid Association (ETA) statement for the indications of post-surgical RAI therapy in DTC. Questions about which patients are candidates for RAI therapy, which activities of RAI can be used, and which modalities of pre-treatment patient preparation should be used are addressed in the present guidelines.

miRNA-128 modulates bone neoplasms cells proliferation and migration through the WNT/β-catenin and EMT signal pathways

BACKGROUND

Bone neoplasms present poor prognosis due to recurrence and metastasis. Although the role microRNAs (miRNAs) in inhibiting growth and metastasis of bone neoplasms has been investigated, the underlying potential molecular mechanisms mediated by miRNA-128 (miR-218) for the invasiveness of bone neoplasms cells are still not completely understood. The purpose of this study was to identify the regulatory mechanisms of miR-218 in bone neoplasms cells.

METHODS

Western blotting, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), Counting Kit-8 assay, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, luciferase activity assay immunofluorescence, and immunohistochemistry were used to analyze the regulatory effects of miR-218 on bone neoplasms cells.

RESULTS

Here, the results showed that transfection of miR-128 suppressed bone neoplasms cells proliferation, migration, and invasion. Genetic knockdown of miR-128 in bone neoplasms cells suppressed the activation of the Wnt/β-catenin and epithelial-mesenchymal transition (EMT) signaling pathways. Activation of Wnt or EMT blocked miR-128-inhibited cells proliferation and migration in bone neoplasms cells. Exogenously introduced miR-128 markedly inhibited tumor regeneration in bone neoplasms xenograft models.

CONCLUSIONS

These results define a tumor-regulated function for miR-128 in bone neoplasms by down-regulation of the Wnt/β-catenin and EMT signal pathways, which provided a potential target for bone neoplasms gene therapy.

Comparison of post-therapeutic sequential 131I whole-body scans in the detection of metastatic thyroid cancer

BACKGROUND

The aim was to compare the detect ability of three sequential 131I whole-body scans (tri-WBS) on the second, third, and fourth day after 131I therapy for metastatic thyroid cancer.

METHODS

Differentiated thyroid cancer patients who received oral high-dose 131I therapy underwent routinely tri-WBS on the second, third, and fourth day after total or near-total thyroidectomy in Zhongshan Hospital, Fudan University. We enrolled 137 patients with 261 tri-WBSs in this study between January 2015 and November 2017. The inclusion criteria was that at least one metastasis was found in the tri-WBS. We classified radioactive uptake of metastatic lesions by visual assessment into three grades: grade 0 = no uptake, grade 1= suspicious uptake, and grade 2 = definite uptake. The fourth day 131I WBS images were also compared with concurrent pre-therapeutic 99mTc-pertechnetate WBS images when available. We also analyzed the serum Tg levels of probably statistical difference in the patients with only lymph node, lung, bone, and multiple metastases when they underwent the first radioiodine ablation.

RESULTS

A total of 722 metastatic accumulations were identified in the final decisions, including 293 lymph node metastases, 261 nodular pulmonary metastases, 49 diffuse bilateral pulmonary metastases, 106 bone metastases, and 13 other metastases. The differences of intensity of uptake in sequential three day images were significant in visualization of lymph node metastasis (χ2=124.432, P<0.001), nodular pulmonary metastasis (χ2=160.334, P<0.001), diffuse bilateral pulmonary metastasis (χ2=41.710, P<0.001), and bone metastasis (χ2=22.118, P<0.001) in our study. Compared to the second day scans, the fourth day scans detected 87 (29.70%) more metastatic lymph nodes, 111 (42.53%) more nodular pulmonary metastases, 26 (53.06%) more diffuse bilateral pulmonary metastases and 17 (16.95%) more bone metastases. The differences of intensity of uptake between 99mTc-pertechnetate WBS and the fourth day 131I WBS were significant in visualization of lymph node metastasis (χ2=172.624, P<0.001), nodular pulmonary metastasis (χ2=111.004, P<0.001), diffuse bilateral pulmonary metastasis (χ2=17.400, P<0.001) and bone metastasis (χ2=46.298, P<0.001). The means of RTg in the patients with only lymph node, lung, bone metastasis, and multiple metastases were 47.20, 76.58, 89.00, and 91.56, respectively. The differences of serum Tg levels in the patients with only lymph node, lung, bone metastasis, and multiple metastases were significant (χ2=35.850, P<0.001).

CONCLUSIONS

The detect ability of tri-WBS was significantly different even for consecutive three-day images on the second, third, and fourth day after 131I therapy for metastatic thyroid cancer. There was a linear trend of increasing 131I uptake from the second to fourth day 131I WBS. The pre-therapy 99mTc-pertechnetate WBS demonstrated a poor ability to detect metastatic thyroid cancer compared to 131I WBS. There was an increasing trend of the means of RTg in patients with more extensive metastases.

Reappraisal of the indication for radioiodine thyroid ablation in differentiated thyroid cancer patients

Radioactive iodine therapy is administered to patients with differentiated thyroid cancer (DTC) for eradication of thyroid remnant after total thyroidectomy or, in patients with metastatic disease, for curative or palliative treatment. In past years, thyroid remnant ablation was indicated in almost every patient with a diagnosis of DTC. Nowadays, careful revision of patients' outcome has introduced the concept of risk-based selection of patients candidate to thyroid remnant ablation. The present review aims to underline the indications for thyroid remnant ablation and to address methodologies to be employed.

Recommendations for post-surgical thyroid ablation in differentiated thyroid cancer: a 2015 position statement of the Italian Society of Endocrinology

Post-surgical ablation of thyroid remnant with radioactive iodine (RAI) in differentiated thyroid cancer (DTC) is aimed to destroy any thyroid remnant in the thyroid bed (remnant ablation) and any microscopic foci of cancer cells eventually present within the thyroid remnant (adjuvant therapy). The present text is an attempt to offer practice guidelines for the indication of thyroid ablation and the preparation of DTC patients considering the latest achievement in the field and the changing epidemiology of DTC observed in the last 10 years.

METHODOLOGY

The executive committee of the Italian Society of Endocrinology appointed a task force of thyroid cancer expert including Nuclear Medicine Physicians and Endocrinologists to provide a consensus on the post-surgical ablation in thyroid cancer patients. The task force had no conflict of interest and had no commercial support. A number of specific topics were selected and the members selected relevant papers by searching in the Pubmed for articles published from 2000 to January 2015. Selected studies were categorized by level of evidence, and the recommendations were graded according to the level of evidence as high (A), moderate (B), or low (C).

Clinical analysis of a patient with a benign lesion of the pharynx misdiagnosed as functional thyroid cancer metastasis

Papillary thyroid carcinoma (PTC) usually has a lower malignancy rate and better prognosis than other types of thyroid cancer. It tends to spread through the lymphatic system, and the percentage of lymph node metastasis to the neck is 50-70% in patients at the time of diagnosis. Iodine-131 (¹³¹I) whole-body scanning is very valuable in the diagnosis and positioning of functional metastatic lesions. However, a variety of comprehensive test results are frequently required to make an appropriate judgment. The present case report describes the case of a patient with PTC where a benign lesion of the pharynx was misdiagnosed as functional metastasis. Some remnant thyroid tissue and an abnormal accumulation of ¹³¹I in the oropharynx and at the right side of the neck were observed by ¹³¹I whole-body scanning one week after the first therapeutic dose. Following the second therapeutic dose, quasi-circular trapping of ¹³¹I by the pharynx persisted. Magnetic resonance imaging enhanced scanning of the oropharynx showed markedly uneven enhancement inside the lesion, and it was considered as a metastatic lesion. However, the serological test results of the patient revealed that there was no increase in the thyroglobulin level and did not support the diagnosis of progressive disease. Therefore, a biopsy on the lesion was conducted under local anesthesia. The histopathological examination exhibited salivary gland tissue and chronic inflammation. Thus, it was necessary to analyze the imaging results, as well as serologic testing outcomes and pathological findings comprehensively, in order to make the correct diagnosis.

The Effect of Diagnostic Absorbed Doses from 131I on Human Thyrocytes in Vitro

Background: Administration of diagnostic activities of ¹³¹I, performed in order to detect thyroid remnants after surgery and/or thyroid cancer recurrence/metastases, may lead to reduction of iodine uptake. This phenomenon is called “thyroid stunning”. We estimated radiation absorbed dose-dependent changes in genetic material, in particular in sodium iodide symporter (NIS) gene promoter, and NIS protein level in human thyrocytes (HT). Materials and Methods: We used unmodified HT isolated from patients subjected to thyroidectomy exposed to ¹³¹I in culture. The different ¹³¹I activities applied were calculated to result in absorbed doses of 5, 10, and 20 Gy. Results: According to flow cytometry analysis and comet assay, ¹³¹I did not influence the HT viability in culture. Temporary increase of 8-oxo-dG concentration in HT directly after 24 h (p < 0.05) and increase in the number of AP-sites 72 h after termination of exposition to 20 Gy dose (p < 0.0001) were observed. The signs of dose-dependent DNA damage were not associated with essential changes in the NIS expression on mRNA and protein levels. Conclusions: Our observation constitutes a first attempt to evaluate the effect of the absorbed dose of ¹³¹I on HT. The results have not confirmed the theory that the “thyroid stunning” reduces the NIS protein synthesis.

Imaging of the thyroid and parathyroid glands

Current multimodal imaging techniques offer practicing providers the adequate framework to plan and accomplish care for patients with thyroid and parathyroid disorders. Available imaging modalities include ultrasonography (US), nuclear scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI). US remains the most cost-effective and the safest approach for the initial evaluation of the thyroid gland. Parathyroid subtraction scintigraphy provides localization of pathologic parathyroid glands with the greatest sensitivity. Localizing imaging studies allow for surgical planning with minimal risk and morbidity to the patient. CT scan and MRI play an adjunctive role in the further characterization of neck pathology.

Revised American Thyroid Association management guidelines for patients with thyroid nodules and differentiated thyroid cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the publication of the American Thyroid Association's guidelines for the management of these disorders was published in 2006, a large amount of new information has become available, prompting a revision of the guidelines.

METHODS

Relevant articles through December 2008 were reviewed by the task force and categorized by topic and level of evidence according to a modified schema used by the United States Preventative Services Task Force.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to optimal surgical management, radioiodine remnant ablation, and suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using ultrasound and serum thyroglobulin as well as those related to management of recurrent and metastatic disease.

CONCLUSIONS

We created evidence-based recommendations in response to our appointment as an independent task force by the American Thyroid Association to assist in the clinical management of patients with thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

Recombinant thyrotropin use in children and adolescents with differentiated thyroid cancer: a multicenter retrospective study

CONTEXT

Although recombinant human TSH (rhTSH) is widely used in differentiated thyroid cancer (DTC) to aid diagnostic follow-up procedures and radioiodine thyroid remnant ablation, almost all clinical investigation was in adults.

OBJECTIVE

The aim of this study was to characterize rhTSH clinical safety and peak TSH response in DTC patients 18 yr old or younger.

DESIGN AND SETTING

We conducted a retrospective study involving 23 tertiary referral centers in 12 European, Asian, and Oceanian countries.

PATIENTS

One hundred DTC patients (69% female, 31% male, 84% papillary, 61% N1, 18% M1) ages 4.9-18 yr at first rhTSH administration were studied.

INTERVENTIONS

A total of 181 rhTSH courses were administered (range, one to eight per patient; 42% of patients received two or more courses), 92% using the approved adult regimen (one 0.9 mg im injection daily on two consecutive days), 34% including thyroid hormone withdrawal for less than 7 d ("mini-THW").

MAIN OUTCOME MEASURES

Clinical adverse event (AE) incidence, type, and severity, and peak post-rhTSH serum TSH concentrations were assessed.

RESULTS

No clinical AEs occurred in 88% of rhTSH courses. Most common clinical AEs were nausea (5% of courses) and vomiting (3%). Multiple or severe AEs were rare (0.6% and 2.8% of courses, respectively); serious AEs were absent. Peak TSH concentration post-rhTSH exceeded 25 mU/liter in approximately 98% of courses. In logistic regression analyses, the rhTSH regimen, "mini-THW," peak TSH concentration, body mass index (BMI), or peak TSH concentration/unit of BMI were not associated with clinical AE occurrence. In analyses of covariance, higher BMI was associated with lower peak TSH concentrations.

CONCLUSIONS

rhTSH was clinically well tolerated in pediatric DTC patients although courses preponderantly comprised the adult regimen, and repeated courses were frequent. Both the adult and reduced-dose regimens almost always sufficiently elevate TSH in children and adolescents.