[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.

[Dual ectopic thyroid: subclinical hypothyroidism after extirpation of a submaxillary mass]. / Ectopia tiroidea dual: hipotiroidismo subclínico tras exéresis de una masa submandibular.

Ectopic thyroid tissue is a rare clinical entity, and more so when it is present in two different locations. We present the case of a 38-year-old euthyroid woman with submandibular and lingual ectopic thyroid tissue in the absence of a normally located thyroid gland, diagnosed after the extirpation of an asymptomatic mass misdiagnosed as a neoplasm of the submaxillary gland. Despite its low frequency, the possibility of ectopic thyroid should be considered when making a differential diagnosis of neck masses, using ultra-sound, thyroid scan and ultrasound-guided fine-needle aspiration biopsy.

Individualised dosimetry in patients with differentiated thyroid cancer based on external dose-rate. Optimisation of the number of measurements.

OBJECTIVES: To compare the results of individual dosimetry in differentiated thyroid cancer patients treated with (131)I at our centre with the established limits and dosimetry results of published studies. Analysis of the optimal number of measurements necessary to reduce the impact of dosimetry for the comfort of the patient and, secondly, on the workload of health workers. MATERIAL AND METHODS: Dosimetry was performed in the Nuclear Medicine Department of the University and Polytechnic Hospital La Fe, on 29 patients suffering from differentiated thyroid cancer and treated with activities between 1.02 and 5.51 GBq (mean 2.68 GBq) of (131)I. The Spanish Society of Medical Physics (SEFM) protocol was used, based on measurements of external dose rate adjusted to a bi-exponential curve according to a two compartment model. Different dosimetries were performed on each patient, taking different selections of the available measurements in order to find the optimal number. RESULTS: Results are well below the dosimetry limits, and are consistent with those obtained in other centres. The number of measurements can be reduced from 5, as proposed in the SEFM protocol, to 4 without significant loss of accuracy. Further reducing measures may be justified in individual cases. CONCLUSIONS: The values obtained for the dosimetry quantities are significantly below the established limits. A reduction in measurements can be assumed at the cost of a moderate increase in uncertainty, benefiting the patient.

[Triiodothyronine intoxication. A clinical and phamacokinetic study]. / Intoxicación por triyodotironina. Estudio clínico y farmacocinético.

A woman, thyroidectomised because of a thyroid papillary carcinoma, interrupted temporarily her levothyroxine intake in order to be subjected to an extension study five weeks later. To minimise her symptoms for the first three weeks, a treatment was prescribed consisting of one 25 micro g-capsule of triiodothyronine every 8 hours. Nine days later she complained of abdominal pain, nausea, vomiting, fever of 40 degrees C and chest discomfort. A serum total triiodothyronine of 575.2 nmol/l was measured by chemoluminiscent immunoassay eleven hours after the intake of the latest capsule (normal level: 1.1-2.9 nmol/l). Along the following ten days the patient suffered from delirium, agitation, tachycardia, hypertension, constipation and later diarrhoea, but neither arrythmias nor axillary temperature over 38 degrees C. Fifty-nine measurements of the serum total triiodothyronine were performed in order to determine the kinetics of elimination of this drug. We estimate that the maximal serum concentration after the intake of the latest capsule could be 794.3 nmol/l, i.e. 397 times higher than the mean normal value. The elimination half-life was 24 hours 40 minutes. The charcoal haemoperfusion had no impact on the velocity of elimination. The concentration of triiodothyronine became normal 200 hours after the intake of the latest capsule, but the clinical manifestations still lasted three days more. The pharmacokinetic data suggest that this intoxication could be due to the intake of capsules containing 5 mg of triiodothyronine, i.e. a dose 200 times higher than that prescribed by her physician.

[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.

[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.

[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.

[Pericardial effusion as a possible cause of false positives in I-131 radionuclide scans]. / Derrame pericárdico como posible causa de falso positivo en un rastreo con 131I.

The case of a patient who had undergone surgery for papillary carcinoma of the thyroid is reported. After administering a therapeutic 131I capsule, the radionuclide scan showed a diffuse, "halo-like" thoracic uptake in the precordial region. The patient's normal thyroglobulin levels and the characteristics of radionuclide uptake did not suggest metastasis. Chest radiography and ultrasonography identified pericardial effusion, which was attributed to hypothyroidism.

[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.

[Simple thyroid cyst]. / Quiste simple de tiroides.

Simple or true thyroid cysts are very rare. We only have found one case in which colorless and acellular transparent fluid has been found by means of the fine needle aspiration puncture (FNAP). We report the case of a 33 year old female who first presented with a rapidly growing thyroid nodule. The thyroid scintigraphy revealed the existence of a cold nodule and the ultrasonography showed a lesion having a cystic appearance. The FNAP was performed and was both diagnostic and therapeutic in this case.

[Thyroid scintigraphy and body scanning with 67 Ga in a case of primary thyroid lymphoma]. / Gammagrafía tiroidea y rastreo corporal con 67Ga en un caso de linfoma tiroideo primario.

The case of a 60-year old woman first presented a rapidly growing left cervical mass is presented. The fine needle aspiration-puncture (FNAP) lead to a diagnosis of thyroiditis. Due to the persistence of the symptoms, the FNAP was repeated again but was not conclusive, so that a surgical biopsy was performed. The pathological diagnosis was diffuse large cell primary thyroid lymphoma (PTL). The PTL is a rare entity that accounts for less than 1% of all the Non-Hodgkin's lymphomas. The thyroid scintigraphy showed the existence of a cold nodule in the left thyroid lobule and the 67Ga scan revealed a large abnormal lesion in the mediastinum that extended to the right latero-cervical region. After two chemotherapy courses, the 67Ga scan was normal.

[Value of 123I-MIBG scanning, neuron-specific enolase and serum ferritin in the diagnosis and follow-up of patients with neuroblastoma]. / Valor del rastreo con 123I-MIBG, enolasa neuronal específica y ferritina sérica en el diagnóstico y seguimiento de pacientes con neuroblastoma.

INTRODUCTION: The neuroblastoma (NB) is one of the most common pediatric malignant neoplasms. The most commonly used tumor markers in the diagnosis and follow-up of this tumor are the serum neuron-specific enolase (NSE), ferritin and lactic dehydrogenase and urinary vanillymandelic and homovanillic acid. The common imaging modalities are CT, MRI and 123I or 131I-meta-iodobenzylguanidine scintigraphy. AIM: The aim of this study is to assess the value of 123I-meta-iodobenzylguanidine (MIBG) scintigraphy and serum determinations of NSE and ferritin in the diagnosis and evolution of NB patients. MATERIAL AND METHODS: 20 patients (8 female, 12 male) whose ages ranged from 2 months to 9 years with a mean age of 2.64 years diagnosed of NB. 47 123I-MIBG scans, 47 NSE determinations and 47 ferritin ones were selected. RESULTS: At the time of diagnosis, 100% of the 123I-MIBG scans were positive. 65% of NSE determinations presented clearly pathological levels and 15% were very near to the cut-off point. Only 45% of the ferritin levels were increased. The differences between the lesions visible by 123I-MIBG scanning before and 3 months after treatment as well as NSE and ferritin levels were studied. When the Student's T test was applied, we found statistically significant pre and post-treatment differences in 123I-MIBG scanning and NSE. In the case of ferritin, there was no statistical significance in spite of the decrease in the values. The direct correlation and Spearman correlation between laboratory data and 123I-MIBG scanning as well as correlation between NSE and ferritin were also studied. There was a good correlation between 123I-MIBG and NSE and between NSE and ferritin. We have also studied the data in 7 relapses. CONCLUSIONS: 123I-MIBG scintigraphy and serum determination of NSE are two successful diagnostic tools for the diagnosis and evolution of NB patients.

Metástasis coroídea de carcinoma papilar de tiroides: subtipo tall cell / Choroidal metastasis of papillary thyroid carcinoma: tall cell subtypes

Se presenta un caso de metástasis coroidea de un cáncer papilar de tiroides. La metástasis es el mecanismo más frecuente de la aparición de patología ocular maligna. Sin embargo el tumor primario más frecuente es el de la mama y del pulmón seguido por riñón, testículo, próstata e intestino. El cáncer de tiroides es raro y menos frecuente aún es que envíe metástasis a la coroides. El paciente presentaba además metástasis a huesos largos, tórax y cerebro. La lesión coroidea fue tratada con radioterapia con mal resultado