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.

Radioembolization in patients with hepatocellular carcinoma: a series of 53 cases.

OBJECTIVE: To contribute our results to increase the scientific evidence about the use of radioembolization in the management of patients with hepatocellular carcinoma. MATERIAL AND METHODS: This retrospective review included 53 patients with hepatocellular carcinoma treated with radioembolization at our center. Patients were classified according to the BCLC algorithm in detail according to their Child-Pugh functional status. We analyzed survival using the Kaplan-Meier method. We used Cox regression analysis to determine clinically significant parameters, including the doses administered in the parameters studied. RESULTS: Patients ranged in age from 28 to 86 years (mean, 60 years). A total of 61 procedures were done. The mean activity administered was 2.8GBq (0.7-6.4GBq), with a mean dose of 229.9Gy (74-425.9Gy) administered in the tumor. Progression-free survival was 6.7 months and overall survival was 12.8 months. Differences in disease-free survival according to BCLC and Child-Pugh classification were not significant (p=0.848 and p=0.252, respectively). The clinical parameters that were significantly different with respect to overall survival were bilirubin levels (p<0.001), pretreatment transaminase levels (AST) (p=0.022), Child-Pugh subclassification (p=0.003), and dose administered in the tumor (p=0.001). Only one patient had a severe adverse reaction, developing posttreatment liver failure resulting in death. CONCLUSIONS: Radioembolization is safe and efficacious in the treatment of patients with hepatocellular carcinoma. Liver function and the doses received by the tumor are key parameters for the efficacy of treatment. The increase in the scientific evidence supports the inclusion of this technique in treatment guidelines.

Peptide receptor radionuclide therapy with [177Lu]Lu-DOTA-TATE.

This continuing education aims to present in a clear and easy-to-understand way, the biology of neuroendocrine tumors (NETs), the characteristics of somatostatin receptors, the selection of patients for radiolabelled peptide therapy (PRRT), the inclusion criteria to benefit from treatment with the minimum possible adverse effects, the administration protocol, follow-up and response evaluation. The functional imaging studies necessary to explore the biology of the tumor and to individualize the treatment are also carried out, and constitute the cornerstone for the development of teragnosis. Clinical trials are being developed to better define the position of PRRT within the broad therapeutic options, and among the future perspectives, there are several lines of research to improve the objective response rate and survival with PRRT, focused on the development of new agonists and somatostatin receptor antagonists, new radionuclides and radiosensitizing combination therapies. In conclusion, PRRT is a great therapeutic, well-tolerated and safe tool with generally mild and self-limited acute side effects, that must be sequenced at the best moment of the evolution of the disease of patients with NET. Candidate patients for PRRT should always be evaluated by a multidisciplinary clinical committee.

[Application of ICRP-103 in the calculation of effective dose associated to nuclear medicine tests]. / Aplicación de los factores de ponderación de la Comisión Internacional de Protección Radiológica 103 en el cálculo de la dosis efectiva asociada a las exploraciones de Medicina Nuclear.

OBJECTIVE: Re-evaluate the effective dose (E) of typical nuclear medicine procedures using the new ICRP-103 weighting factors and the latest dosimetry data and relate E with Background Equivalent Radiation Time (BERT). MATERIAL AND METHODS: Effective dose associated with radiopharmaceuticals and nuclear medicine procedures has been calculated for the following ages: adult, 15, 10, 5 and 1 year. Dosimetry data have been extracted from ICRP-106, ICRP-80, ICRP-53 and/or manufacturer's brochure. RESULTS: The relationship of the data of effective dose associated with radiopharmaceuticals and explorations is shown. The new tissue weighting factors result in a decreased value of the effective dose, except in cases that particularly affect the breast, in which it increases. The effective dose associated with nuclear medicine procedures is in the range 0.1-60 mSv. BERT ranges from a few days to 20 years. The effective dose associated to tests in children is generally higher than the effective dose for an adult. CONCLUSIONS: The results shown in this paper are an updated collection of effective dose values for commonly used radiopharmaceuticals in nuclear medicine. Expressing the effective dose equivalent time in units of natural radiation helps to explain issues associated with radiation exposure to patients and healthcare personnel.

[Somatostatin receptor scintigraphy in pediatric bronchial carcinoid tumor]. / Gammagrafía con análogos de la somatostatina en el diagnóstico y el seguimiento del carcinoide bronquial pediátrico.

INTRODUCTION: Carcinoid tumor is a rare neuroendocrine neoplasm with different locations, the most frequent ones during the pediatric age being the appendix and lung. Scintigraphy with (111)In-DTPA-d-Phe(1)-octreotide has led to an importance advance in the diagnosis of extension in carcinoid tumor patients. We present three pediatric patients with bronchial carcinoid studied with somatostatin analogue scintigraphy (SSRS). CLINICAL CASES: The first patient (9 years) was studied using the SSRS after surgery due to carcinoid tumor in the right lower lobe in which tumor remains was observed (this being clearer in the tomography study). The second patient (10 years) presented due to endobronchial tumor in the left lower lobe together with atelectasis of the LUL and emphysema of the LLL. Radiology imaging techniques suggested the differential diagnosis between the endobronchial carcinoid tumor or plasma cells or foreign body gramuloma. The SSRS showed an abnormal deposit of activity in the left hemithorax consisted with carcinoid tumor. No other areas suggesting metastasis were observed. After the surgery (endobronchial resection), new controls with SSRS showed absence of disease. The third patient (12 years) came after a lobectomy (RUL) due to bronchial carcinoid. The SSRS did not show any abnormal areas of activity. In the subsequent control (3 months), a deposit of activity was observed in the middle third of the right hemithorax, after which a lobectomy was performed (RLL and ML) that showed small remains of neuroendocrine carcinoid. Subsequent controls were negative. CONCLUSION: The SSRS has demonstrated great utility in the diagnosis, follow-up and staging of pediatric patients, carriers of neuroendocrine carcinoid tumors.

Radioembolization in patients with hepatocellular carcinoma: a series of 53 cases. / Radioembolización de hepatocarcinomas: a propósito de 53 casos.

OBJECTIVE: To contribute our results to increase the scientific evidence about the use of radioembolization in the management of patients with hepatocellular carcinoma. MATERIAL AND METHODS: This retrospective review included 53 patients with hepatocellular carcinoma treated with radioembolization at our center. Patients were classified according to the BCLC algorithm in detail according to their Child-Pugh functional status. We analyzed survival using the Kaplan-Meier method. We used Cox regression analysis to determine clinically significant parameters, including the doses administered in the parameters studied. RESULTS: Patients ranged in age from 28 to 86 years (mean, 60 years). A total of 61 procedures were done. The mean activity administered was 2.8 GBq (0.7-6.4 GBq), with a mean dose of 229.9Gy (74-425.9Gy) administered in the tumor. Progression-free survival was 6.7 months and overall survival was 12.8 months. Differences in disease-free survival according to BCLC and Child-Pugh classification were not significant (p=0.848 and p=0.252, respectively). The clinical parameters that were significantly different with respect to overall survival were bilirubin levels (p<0.001), pretreatment transaminase levels (AST) (p=0.022), Child-Pugh subclassification (p=0.003), and dose administered in the tumor (p=0.001). Only one patient had a severe adverse reaction, developing posttreatment liver failure resulting in death. CONCLUSIONS: Radioembolization is safe and efficacious in the treatment of patients with hepatocellular carcinoma. Liver function and the doses received by the tumor are key parameters for the efficacy of treatment. The increase in the scientific evidence supports the inclusion of this technique in treatment guidelines.

[Interstitial nephritis demonstrated by 67Ga-citrate scintigraphy within a diagnosis of fever of unknown origin]. / Nefritis intersticial demostrada mediante gammagrafía con 67Ga-citrato en el contexto de fiebre de origen desconocido.

We present a clinical case of a 54-year-old woman that was admitted in our hospital with the diagnosis of fever of unknown origin. All the laboratory tests and imaging techniques did not manage to establish the fever's aetiology until a (67)Ga-citrate scan was performed and kidney uptake was observed, which lead to the clinical suspicion of drug-induced interstitial nephritis. The renal biopsy confirmed the diagnosis. This finding allowed corticoid therapy and cure.

Use of 177Lu-dotatate in the treatment of iodine refractory thyroid carcinomas. / Uso del 177Lu-DOTATATE como terapia en carcinomas de tiroides yodorrefractarios.

In a patient with a differentiated thyroid cancer the standard treatment protocol to be followed is surgery, ablation of thyroid remnants with 131Iodine (131I), and TSH suppression. However, the treatment with 131I is not effective in some cases, and it no longer becomes a therapeutic option due to cell de-differentiation with loss of 131I uptake. Systemic treatment can be used as other options, although patients are not always responsive; thus, the disease may progress and therapeutic options may run out. Endocrine tumours may express somatostatin receptors,and this characteristic has been used, not only for diagnosis, but also for their treatment through somatostatin analogue labelling with radioactive isotopes. This was the case of a patient suffering from iodine-refractory follicular thyroid carcinoma, with somatostatin receptors expression, treated with 177Lu-DOTATATE, showing an excellent clinical and analytical response.

Beyond the Briganti nomogram: Individualisation of lymphadenectomy using selective sentinel node biopsy during radical prostatectomy for prostate cancer. / Más allá del nomograma de Briganti: individualización de la linfadenectomía utilizando la biopsia selectiva del ganglio centinela durante la prostatectomía radical por cáncer de próstata.

OBJECTIVE: To validate the technique of selective sentinel node biopsy for diagnosing and staging intermediate to high-risk prostate cancer by comparing the technique with conventional extended lymphadenectomy (eLFD) in a prospective, longitudinal comparative study. METHODS: We applied the technique to 45 patients. After an intraprostatic injection of 99mTc-nanocolloid and preoperative single-photon emission computed tomography (SPECT/CT), we extracted the sentinel lymph nodes, guided by a portable Sentinella® gamma camera and a laparoscopic gamma-ray detection probe. The eLFD was completed to establish the negative predictive value of the technique. RESULTS: SPECT/CT showed radiotracer deposits outside the eLFD territory in 73% of the patients and the laparoscopic gamma probe in 60%. The mean number of active foci per patient was 4.3 in the SPECT/CT and 3.2 in the laparoscopic gamma probe. The mean number of extracted sentinel lymph nodes was 4.3 (0-14), with 26% outside the eLFD territory. The lymph nodes were metastatic in 10 patients (22%), 6/40 (15%) when the prostatectomy was the primary treatment. In all cases with metastatic lymph nodes, there was at least one positive sentinel node. Metastatic sentinel lymph nodes were found outside the eLFD territory in 3/10 patients (30%). The sensitivity was 100%, the specificity was 94.73%, the positive predictive value was 81.81%, and the negative predictive value was 100%. CONCLUSION: Selective sentinel node biopsy is superior to eLFD for diagnosing lymph node involvement and can avoid eLFD when metastatic sentinel lymph nodes are not found (85%), with the consequent functional advantages.

[Relative renal function based on DMSA uptake corrected for volume: normalized relative renal function]. / Función renal relativa basada en captación de ácido dimercaptosuccínico corregida por volumen: función renal relativa normalizada.

OBJECTIVE: Relative renal function (RRF) quantification based on dimercaptosuccinic acid (DMSA) uptake is an established method for determining differential renal function. An abnormal kidney size may lead to an alteration in its RRF value, although it has no dysfunction. Therefore, it is useful to correct RRF values taking into account relative renal volumes, thus obtaining the normalized relative renal function (NRRF). The feasibility of the method used for volume correction, differences with respect to usual quantification and different normality intervals were studied. MATERIAL AND METHODS: A total of 187 DMSA renal scintigraphies (130 children and 57 adults) were studied. RRF was quantified and volume corrected to obtain NRRF. Patients were classified as normal or pathological using various normality intervals for NRRF. A second classification was performed depending on how the diagnostic changed after volume correction. RESULTS: An increase of pathological diagnosis was observed after volume correction, mainly in children. Using an intermediate estimation for the normality interval, 53% of the initially pathological diagnosis for children may be caused simply by different renal volumes. CONCLUSIONS: NRRF provides complementary information to RRF and helps to distinguish between a smaller kidney and a really hypofunctioning one in cases with abnormal RRF.

[Scintigraphy with 111In-octreotide in a case of primary hepatic gastrinoma]. / Gammagrafía con 111In-octreotide en un caso de gastrinoma hepático primario.

Gastrinomas are uncommon tumors which are difficult to locate. They are often located in the head of the pancreas. About two-thirds of them are malignant, their growth is slow and they usually metastasize in the liver. In about 25% of cases, the Zollinger-Ellison (Z-E) syndrome is included in the multiple endocrine neoplasm type 1 syndrome (MEN 1).A 14-year old male patient presenting an episode of abdominal perforation which required emergency surgery is reported. The abdominal ultrasonography, CT scan and magnetic resonance revealed a single lesion in the left liver lobe, suggesting metastasis. Significantly increased levels of serum gastrin suggested a diagnosis of Z-E syndrome. A study with 111In-octreotide was required to locate the primary tumor and evaluate its extent. The scintigraphy showed only one abnormal uptake focus in the left liver lobe. Post-surgery scintigraphy studies revealed the presence of metastatic adenopathies which were removed after a second surgery. No pathologic findings were observed in the last nuclear medicine study. The somatostatin receptor scintigraphy is the most sensitive method to locate primary gastrinomas and to assess the tumoral dissemination in patients with Z-E Syndrome.

[Uptake of 99mTc-diphosphonates due to brain infarction]. / Captación de 99mTc-difosfonatos por un infarto cerebral.

The case of a patient who came to the Nuclear Medicine Department for a bone scintigraphy to rule out bone metastasis because of a lung neoplasm is presented. Some days before, the patient had suffered a right brain infarction. 99mTc-MDP uptake could be seen in the infarction area. Different mechanisms of 99mTc phosphates deposition in tissues other than bones are reviewed in this article.

[Normally functioning ectopic thyroid in adults. Apropos of 4 cases]. / Tiroides ectópico normofuncionante en la edad adulta. A propósito de cuatro casos.

Four cases are presented of ectopic thyroid tissue in adult women who underwent for thyroid study for different motives. Radioisotopic uptake was absent in the usual thyroid location. Thyroid function was normal in every case and no psychomotor abnormalities were present. In one case, echography revealed an atrophic thyroid in the usual location in association with thyroid ectopy. The literature of thyroid ectopy was reviewed and the preponderant role of radioisotopic scan is underlined, together with thyroid echography in the imaging diagnosis of neck masses.

[Evaluation of the usefulness of the antimyosin monoclonal antibody (AMA) uptake in the diagnosis of heart transplant (HT) rejection]. / Valoración de la utilidad del índice de captación de anticuerpos monoclonales antimiosina (AMA) en el diagnóstico de rechazo en el trasplante cardíaco (TC).

OBJECTIVE: To ascertain whether a given level of antimyosin monoclonal antibody (AMA) uptake in the endomyocardial biopsy (EMB) can identify patients with rejection. MATERIAL AND METHOD: 186 examinations were performed on 65 patients (8 women and 57 men) with orthotopic heat transplant (HT): Mean age 51 +/- 13 years. There were 3 examinations per patient (range 1-6). The studies were conducted 13 to 880 days after the HT. The C/p uptake indexes were obtained according to the Carrió y cols. method and the results were compared with the biopsy findings. Rejection was considered to be when the biopsy showed at least one site of necrosis. RESULTS: 1) We analyzed the C/P index in accordance with the post-HT interval and with the degree of rejection obtained by EMB. No group showed any significant differences between the patients with an without rejection (p > 0,05). 2) We applied a variable threshold based on post-HT interval, using an exponential curve defined on the basis of the interval of the values corresponding to patients without rejection and good progress compared with that of the rejection patients. This approach also did not contribute any improvement compared to the use of a fixed threshold due to the significant overlay of the values for patients with and without rejection. 3) Finally, we analyzed the individual evolution of the C/P indexes for each patient in terms of time. In patients whose clinical progress was good, the C/P indexes were observed to drop progressively over time. In those whose clinical progress was poor, abrupt increases in the index values were observed. CONCLUSION: We were unable to differentiate significantly between patients with and without rejection in EMB using fixed and variable thresholds of the C/P index. However, the different patterns of evolution for each patient provide information on the lack of complications and could be used as a follow-up technique.

[Hepatobiliary scintigraphy in a case of acute cholecystitis in childhood]. / Gammagrafía hepatobiliar en un caso de colecistitis aguda en la infancia.

Acute cholecystitis is an uncommon disease in childhood. Few cases in patients under 10 years of age have been found in literature. An eight-year old male patient with no history of interest who had acute acalculous cholecystitis was reported. Ultrasonographic and isotopic studies led to the diagnosis and control of the patient's evolution.

[Association of thyroid hemiagenesis and Graves disease]. / Asociación de hemiagenesia tiroidea y enfermedad de Graves.

Thyroid hemiagenesis is a very infrequent abnormality. We present a case of Graves disease associated to a congenital hemiagenesis of the thyroid gland. The thyroid scintigraphy, ultrasonography and laboratory analysis (that showed the existence of thyroid hyperfunction and the present of thyroid stimulating antibodies) were decisive in the diagnosis.