Update on iodine-refractory differentiated thyroid carcinoma.

Radioiodine therapy represents a fundamental pillar in the routine adjuvant therapy of patients with high-risk differentiated thyroid carcinoma. However, a non-negligible percentage of these patients will develop iodine refractoriness, showing a worse prognosis, as well a lower survival, which demonstrates a clear need to explore different therapeutic approaches. Iodine refractory patient treatment continues to be a challenge, currently having different novel therapeutic options that should be known by the different specialties related to differentiated thyroid carcinoma (DTC). The aim of this work is to review iodine refractory thyroid carcinoma treatment, focusing especially on the definition of iodine refractoriness, highlighting its importance due to its high mortality, and introducing the different therapeutic options available for these patients.

18F-DCFPyL PET/CT guidelines.

The objective of this guide is to provide to nuclear medicine physicians a tool based on scientific evidence and prepared by consensus of experts, to perform the 18F-DCFPyL PET/CT procedure with safely and efficiently for patients with prostate cancer who present PSMA overexpression. For them, some recommendations will be established for 18F-DCFPyL PET/CT examination: reconstruction parameters, presentation of the images and their interpretation. The possible false positives of the procedure will be analysed, how to interpret them and how to avoid them. Finally, all exploration should lead to the preparation of a report that answers the clinician's question. For this, it is recommended to prepare a structured report that includes the PROMISE criteria as well as the classification of the findings according to PSMA-RADS parameters.

[Response of thyroglobulin, anti-thyroglobulin antibodies, TSH, FT4 and total T3 after rhTSH stimulation in differentiated thyroid carcinoma]. / Respuesta de tiroglobulina, anticuerpos antitiroglobulina, TSH, FT4 y T3 total tras estimulación con rhTSH en carcinoma diferenciado de tiroides.

OBJECTIVE: To analyse the behaviour of serum thyroglobulin (Tg), antithyroglobulin antibodies (TgAb), thyrotropin (TSH), free thyroxine (FT4) and total triiodothyronine (TT3) levels at each time during the rhTSH stimulation protocol in patients with differentiated thyroid carcinoma (DTC). MATERIALS AND METHODS: We carried out 117 rhTSH stimulations in DTC patients. We determined the serum levels of Tg, TgAb, TSH, FT4 and TT3 at baseline and 24, 48 and 96 hours after beginning stimulation, using RIA or IRMA. The software program SPSS 15.0 was used for statistical analysis of data. RESULTS: We found statistically significant differences between the mean Tg values at different times (2.08 ng/ml baseline; 2.64 ng/ml at 24 hours; 4.98 ng/ml at 48 hours; 6.59 ng/ml at 96 hours), reaching maximum values at 96 hours. During this time, we observed the highest percentage of pathological values. After administration of rhTSH, there was a significant increase in the mean TSH value (98.88 mIU/l at 24 hours; 111.10 mIU/l at 48 hours). The mean TSH value at 96 hours decreased approximately 5 times with respect to the mean 48 hour value. We did not observe changes in the TgAb, FT4 or TT3 levels. CONCLUSIONS: The assessment of Tg after rhTSH stimulation should be performed 96 hours after beginning stimulation. Administration of rhTSH causes a significant elevation in serum TSH levels, without modifying serum TgAb, FT4 or TT3 levels.

75SeHCAT scan in bile acid malabsorption in chronic diarrhoea. / Gammagrafía con 75SeHCAT en la diarrea crónica por malabsorción de ácidos biliares.

Chronic diarrhoea is a common entity in daily clinical practice and it leads to a loss in these patients quality of life. It may be the main symptom of multiple ethiologies including bile acid malabsorption (BAM) which has a comparable prevalence to celiac disease. The BAM results from imbalances in the homeostasis of bile acids in the enterohepatic circulation. It can be a consequence of ileal disease or ileal dysfunction (BAM type i), it can be considered idiopathic or primary (BAM type ii) or associated with other gastrointestinal entities (BAM type iii). Among the different diagnostic methods available, 75SeHCAT study is the primary current method due to its sensitivity, specificity, safety and low cost. The main disadvantage is that it's not available in all countries, so other diagnostic methods have appeared, such as serum measurement of FGF19 and C4, however they are significantly more complex and costly. The first-line treatment of bile acid diarrhoea is bile acid sequestrant, such as cholestyramine, which can be difficult to administer due to its poor tolerability and gastrointestinal side effects. These are less prominent with newer agents such as colesevelam. In summary, the BAM is a common entity underdiagnosed and undertreated, so it is essential to establish a diagnosis algorithm of chronic diarrhoea in which the 75SeHCAT study would be first or second line in the differential diagnosis of these patients.

[Alteration in the biodistribution of 99mTc-albumin microspheres after its administration through a canalized umbilical vein]. / Alteración en la biodistribución de 99mTc-microesferas de albúmina por su administración a través de una vena umbilical canalizada.

We present the case of a newborn female patient with a suspected right hypoplastic lung who was referred to our Service to perform a perfusion lung scintigraphy. The tracer (99mTc-albumin microspheres) was injected with a central catheter through the umbilical vein. The lung scan showed abnormal extrapulmonary activity that was attributed to an erroneous canalization (catheter in Arantius duct). A new study, with injection through the peripheral vein, showed the lung perfusion, with a global decrease of activity in the right lung. This case demonstrates a cause of abnormal extrapulmonary perfusion tracer uptake, verifying that using the correct access route is mandatory.

[Nuclear medicine in Spain: high technology 2013]. / Medicina nuclear en España: alta tecnología 2013.

This article details the high technology equipment in Spain obtained through a survey sent to the three main provider companies of equipment installed in Spain. The geographical distribution of high technology by Autonomous Communities and its antiquity have been analyzed.

Actualización en carcinoma diferenciado de tiroides refractario a radioyodo / Update on iodine-refractory differentiated thyroid carcinoma

La terapia con radioyodo constituye un pilar fundamental en la terapia adyuvante de rutina de los pacientes con carcinoma diferenciado de tiroides de alto riesgo. Sin embargo, un porcentaje no despreciable de estos pacientes desarrollaran un estado de refractariedad a este tratamiento, mostrando un peor pronóstico, disminuyendo la supervivencia y la esperanza de vida, lo que demuestra una clara necesidad de explorar distintos abordajes terapéuticos. El tratamiento de los pacientes refractarios al radioyodo sigue siendo un desafío, disponiendo en la actualidad de distintas opciones terapéuticas novedosas que deben ser conocidas por las distintas especialidades relacionadas con el carcinoma diferenciado de tiroides (CDT). El objetivo del presente trabajo es hacer una revisión del CDT refractario al tratamiento con yodo radiactivo, centrándose especialmente en la definición de yodorrefractariedad, destacando su importancia por su elevada mortalidad, e introducir las diferentes opciones terapéuticas disponibles para estos pacientes (AU)

Radioiodine therapy represents a fundamental pillar in the routine adjuvant therapy of patients with high-risk differentiated thyroid carcinoma. However, a non-negligible percentage of these patients will develop iodine refractoriness, showing a worse prognosis, as well a lower survival, which demonstrates a clear need to explore different therapeutic approaches. Iodine refractory patient treatment continues to be a challenge, currently having different novel therapeutic options that should be known by the different specialties related to differentiated thyroid carcinoma (DTC). The aim of this work is to review iodine refractory thyroid carcinoma treatment, focusing especially on the definition of iodine refractoriness, highlighting its importance due to its high mortality, and introducing the different therapeutic options available for these patients (AU)

Validation of stationary phases in (111)In-pentetreotide planar chromatography.

INTRODUCTION: Since Pall-German stopped manufacturing ITLC-SG, it has become necessary to validate alternative stationary phases. OBJECTIVE: To validate different stationary phases versus ITLC-SG Pall-Gelman in the determination of the radiochemical purity (RCP) of (111)In-pentetreotide ((111)In-Octreoscan) by planar chromatography. MATERIAL AND METHODS: We conducted a case-control study, which included 66 (111)In-pentetreotide preparations. We determined the RCP by planar chromatography, using a freshly prepared solution of 0,1M sodium citrate (pH 5) and the following stationary phases: ITLC-SG (Pall-Gelman) (reference method), iTLC-SG (Varian), HPTLC silica gel 60 (Merck), Whatman 1, Whatman 3MM and Whatman 17. For each of the methods, we calculated: PRQ, relative front values (RF) of the radiopharmaceutical and free (111)In, chromatographic development time, resolution between peaks. We compared the results obtained with the reference method. The statistical analysis was performed using the SPSS program. The p value was calculated for the study of statistical significance. RESULTS: The highest resolution is obtained with HPTLC silica gel 60 (Merck). However, the chromatographic development time is too long (mean=33.62minutes). Greater resolution is obtained with iTLC-SG (Varian) than with the reference method, with lower chromatographic development time (mean=3.61minutes). Very low resolutions are obtained with Whatman paper, essentially with Whatman 1 and 3MM. Therefore, we do not recommend their use. CONCLUSIONS: Although iTLC-SG (Varian) and HPTLC silica gel 60 (Merck) are suitable alternatives to ITLC-SG (Pall-Gelman) in determining the RCP of (111)In-pentetreotide, iTLC-SG (Varian) is the method of choice due to its lower chromatographic development time.