Puesta al día: carcinoma paratiroideo / An update on parathyroid carcinoma

Parathyroid carcinoma is a rare malignant disease that presents as a sporadic or familial primary hyperparathyroidism (PHP). The latter is associated with some genetic syndromes. It occurs with equal frequency in both sexes, unlike PHP caused by parathyroid adenoma that is more common in women. It should be suspected in cases of severe hypercalcemia, with high parathyroid hormone levels and a palpable cervical mass. Given the difficulty in distinguishing between parathyroid carcinoma and adenoma prior to the surgery, the diagnosis is often made after parathyroidectomy. The only curative treatment is complete surgical resection with oncologic block resection of the primary tumor to ensure free margins. Adjuvant therapies with chemotherapy or radiation therapy do not modify overall or disease-free survival. Recurrences are common and re-operation of resectable recurrent disease is recommended. The palliative treatment of symptomatic hypercalcemia is crucial in persistent or recurrent disease after surgery since morbidity and mortality are more associated with hypercalcemia than with tumor burden.

Recomendaciones para el uso correcto de densitometría ósea en la práctica clínica. Consenso de la Sociedad Chilena de Endocrinología y Diabetes / Guidelines of the Chilean Endocrinology Society for the correct clinical use of bone densitometry

Osteoporosis is a silent and frequent disease, which increases fracture risk. Approximately half of women and one of five men over 50 years old will suffer an osteoporotic fracture throughout their lives. Dual-energy x-ray absorptiometry (DXA) allows a real bone mineral density (BMD) measurement in different parts of the skeleton and is considered the "gold standard" for quantifying osteoporosis with high accuracy and precision. The Board of the Chilean Society of Endocrinology and Diabetes (SOCHED) required from the Bone Disease Study Group to develop a consensus about the "Correct use of bone densitometry in clinical practice in Chilean population". Therefore, we elaborated 25 questions which addressed key aspects about the indications for a DXA scan, and the details of how to perform and report this test. Since some of the evidence obtained was of low quality or inconclusive, we decided to create a multidisciplinary group of national experts in osteoporosis to develop a consensus in this subject. The group consisted of 22 physicians including endocrinologists, gynecologists, geriatricians, radiologists, rheumatologists and nuclear medicine specialists. Using the Delphi methodology to analyze previously agreed questions, we elaborated statements that were evaluated by the experts who expressed their degree of agreement. The final report of this consensus was approved by the SOCHED board.

Utilidad del estudio PET con FDG en la evaluación de sarcomas de diverso origen y de tumores no sarcoma-no epiteliales / Positron emission tomography with fluorine-deoxyglucose in sarcomas and non-sarcoma non-epithelial tumors

Background: The usefulness of positron emission tomography (PET) with fluorine-deoxyglucose (FDG) in sarcomas and non-sarcoma non-epithelial (NSNE) tumors is not clearly defined. Aim: To report a Chilean experience with NSNE tumors evaluated using PET with FDG. Material and Methods: Retrospective review of the database of a PET laboratory. Demographic data, indications and metabolic findings were compared with conventional imaging in 88 adults and children with diverse bone and soft tissue sarcomas as well as 24 gastrointestinal stromal tumors (GIST), 6 pleural malignant mesotheliomas in adults, and 9 medulloblastomas in children. Results: FDG showed good concordance with conventional imaging in NSNE tumors. It was helpful for staging, restaging, follow-up after treatment and for the detection of new not previously suspected lesions. Conclusions: PET with FDG could have a prognostic role and help in patient management, mainly in musculos-keletal and high grade or less differentiated sarcomas. In GIST, it was a good tool for immunotherapy control.

Neuro – functional and endocrine findings in patients with post-traumatic stress disorder

The authors studied the neuro-functional findings demonstrated by SPECT in a group of 7 patients diagnosed with post traumatic stress disorder (PTSD) and their correlation with endocrinologic and clinical variables. Brain perfusion was assessed using SPECT Tc99m – ECD. The Davidson Trauma Scale (DTS) for post traumatic stress disorder and the abbreviated version of the Beck Depression Inventory (BDI) were used to corroborate clinical impressions. Endocrine measures included: T3, total T4, TSH and cortisol levels. Neuro-functional findings included abnormal radiopharmaceutical uptake in regions involved in the recovery of verbal memories and executive functions (frontal and pre-frontal cortex), and limbic system. No endocrine alterations affecting thyroid or cortisol levels were found. The broad distribution of neuro-functional abnormalities causes us to hypothesize a diffuse etiologic mechanism, possibly involving a dysfunction in the permeability of the blood-brain barrier due to an underlying inflammatory process.

Alteraciones neuro-funcionales y neuro-endocrinas en una cohorte de pacientes que cursan con trastorno por estrés post traumático / Neuroendocrine and neurofunctional alterations in patient with post traumatic stress disorder

El trastorno por estrés post traumático (TEPT) se perfila en la actualidad como una patología emergente debido a las condiciones de vida modernas cada vez más exigentes y al énfasis epidemiológico y en salud mental por pesquisar las consecuencias de traumas cotidianos, como de aquellos derivados de conflictos bélicos o de la acción de fuerzas de seguridad y orden ciudadanos. Se describe que aproximadamente un 8 por ciento de quienes sufren un trauma experimentarán un cuadro clínico compatible con TEPT. Sin embargo, la larga duración y frecuente cronicidad de estos casos demanda un enorme esfuerzo al equipo de salud y costos elevados a los organismos que acogen a estos pacientes. El presente trabajo tiene por objetivo realizar un estudio neuro-funcional, clínico y de laboratorio en una muestra de 7 pacientes que cursan con un cuadro compatible con TEPT. Método: Se evaluó clínicamente a 7 pacientes que cursaban con TEPT, aplicándoseles una escala de evaluación para esta patología (Escala de Davidson) y el inventario de depresión de Beck. Se obtuvieron muestras de sangre con el objeto de evaluar los niveles de cortisol plasmático y hormonas tiroideas T3, T4 y TSH. Finalmente, los sujetos fueron evaluados a partir de la técnica de neuro SPECT delineándose una serie de Regiones e Interés (ROI) involucradas en la neurobiología del TEPT. Resultados: Se reportan para todos los pacientes de la cohorte estudiada valores elevados en escala Davidson para TEPT y en la escala de Beck para depresión (91.85 y 25.28 respectivamente). Se describen valores promedios normales de cortisol plasmático y de hormonas tiroideas T3, T4 y TSH (17.35 ug/dl, 1.34 ng/ml, 6,98 ug/dl y 2,95 uUI/ml respectivamente). Destaca la presencia de hiper-cortisolemia en tres de los pacientes estudiados. Los hallazgos neuro-funcionales se caracterizan por una hiper-perfusión a nivel de córtex fronto-parietal e hipo-perfusión...

Post Traumatic Stress Disorder (PTSD) is one of the most important emergent pathologies in mental health and is usually associated with current post modern´s life styles and with specific traumatic event such as belic conflicts or incident involving criminal behaviors affecting civilians. It is well known that 8% of victims of a traumatic event will develop PTSD. Furthermore, the chronicity and social impairment associated to this clinical entity requires an enormous effort from mental health’s professionals and huge costs to the systems involved in the rehabilitation of these patients. The aim of this study is to evaluate a sample of 7 patients affected from PTSD in order to understand their clinical characteristics, neuro-functional features and possible neuro-endocrine abnormatilies. Method: 7 patient affected with PTSD were clinically evaluated and submitted to a specific-validated post traumatic scale (Davidson scale) and also to a depression inventory (Beck depression inventory). Then, blood samples were taken in order to assess Neuro- endocrine levels of cortisol in plasma and T3, T4 and TSH levels. Finally, the subjects were studied by means of SPECT, delineating specific Region of Interest (ROI) involved in the neurobiological basis of PTSD. Results: we report on, for the entire sample, high scores on both scales used (Davidson scale: 91.85; Beck inventory: 25.28). These results confirm the previously reported high comorbidity between this two clinical entities. We describe average normal values for plasmatic cortisol levels and thyroid hormones levels T3, T4, TSH (17.35 ug/dl, 1.34 ng/ml, 6.98 ug/dl and 2.95 uUI/ml respectively). It is important to remark the presence of hypercortisolemia in 3 of the patients studied. Neuro-functional features were characterized by a cortical fronto-parietal hyper-perfusion and hypo-perfusion on limbic areas. This results were consistently replicated in the entire sample...

Análisis de 1.000 casos de estudios metabólicos en Chile con PET 18Flúor-deoxiglucosa (FDG) / Chilean experience with the use of 18F-deoxyglucose positron emission tomography

Background: Clinical oncology is the main application of 18F-deoxyglucose (FDG) positron emission tomography (PET). Aim: To evaluate the first 1,000 patients studied with FDG PET in Chile. Material and methods: Retrospective analysis of 1,000 patients (aged between 1 and 94 years, 550 females) studied with FDG PET, since 2003. All studies were performed in a high resolution Siemens Ecat-Exact HR (+). All reports were based on the visual analysis of three plane and three-dimensional images. Results: Ninety seven percent of exams were done for oncological indications, mainly lung lesions, lymphoma, colorectal and gastroesophageal, cancer and breast tumors. Only 1 percent of patients had brain tumors. Non tumor neurological indications corresponded to 1.7 percent. Cardiac studies were only 0.3 percent and inflammatory process corresponded to 1 percent. The 5.6 percent corresponded to pediatric population. Six percent of patients were aged less than 18 years and in 50 percent of them, the indication was oncological, mainly lymphomas, brain tumors, endocrine cancers and sarcomas. The remaining 50 percent had a neurological indications, mainly for refractory epilepsy. Conclusions: PET FDG imaging was effective in the management of diverse diseases of children and adults.

Analysis of the initial experience with first PET scanner and 18F -FDG in Chile

La principal aplicación del PET FDG es en el manejo de pacientes oncológicos debido a la alta correlación entre metabolismo glucídico y actividad tumoral. Objetivo: analizar el grupo inicial de pacientes realizados con el primer equipo PET dedicado existente en Chile. Método: Presentamos los primeros 500 casos estudiados con la cámara Siemens HR+ usando FDG producida en las instalaciones de la Comisión Chilena de Energía Nuclear. Resultados: La mayoría de los diagnósticos de referencia fueron de causa oncológica (96 por ciento). Cuatro por ciento fueron estudiados por patología neurológica o desórdenes psiquiátricos y 1 por ciento por viabilidad miocárdica. Lesiones pulmonares, gastrointestinales, linfomas, cánceres de mama, y melanoma fueron las patologías más comunes. Los pacientes con linfoma y lesiones pulmonares, entre otros, están con seguimiento clínico. Hubo buena concordancia con imágenes anatómicas y la histología en los casos en que estuvo disponible. La fusión de FDG con tomografía computada o resonancia magnética ha sido útil. En un significativo número de casos hubo detección de nuevos sitios anormales tumorales. Conclusión: Confirmamos que las imágenes metabólicas con F18-FDG son útiles para la evaluación y manejo del cáncer, en la práctica clínica.

Protocolos de estudio de perfusión miocárdica con radioisotopos en evaluación de cardiopatía coronaria / Studies of myocardial perfusion using radioisotopes in the coronary heart disease

Se revisan los principales protocolos actuales de perfusión miocárdica con técnica isotópica, sus indicaciones, requerimientos y nuevas aplicaciones. Se da especial énfasis a la técnica de SPECT gatillado que agrega parámetros de función a las imágenes tomográficas con mayor valor diagnóstico y pronóstico y también a la introducción de positrones mediante fluordeoxiglucosa en la detección de viabilidad miocárdica.

Cintigrafía ósea: estado actual / Bone scintigraphy: current status

La cintigrafía ósea es un procedimiento de estudio no invasivo utilizado en clínica desde l950 pero que sólo se ha impuesto a partir de l970 fecha en que se introdujeron los rradiofármacos actualmente en uso (fosfatos y fosfonatos Tc-99m). Estos administrados por vía endovenosa se unen por quimioabsorción a los cristales de hidroxiapatita de los focos de regeneración ósea. Esta unión está condicionada por el flujo sanguíneo y la actividad esteoblástica. La cintigrafía ósea, a diferencia de la radiología, traduce función más que morfología. La mayoría de los procesos patológicos regionales del esqueleto determinan aumento reactivo de la actividad osteoblástica y consecuentemente hiperfijación focal del radiofármaco. En experiencia de los autores el 30% de los cintigramas óseos resultan normales (Tipo I); el 30% son inespecíficos (Tipo II) y el 30% dan informaciones (Tipo III) que hacen innecesarios mayores estudios. La mayor utilidad diagnóstica de la cintigrafía ósea radica en el estudio de las lesiones focales tanto malignas como benignas y es actualmente el método de elección para la búsqueda de metástasis, muchas de las cuales no son detectables radiológicamente. En este campo la cintigrafía tiene una sensibilidad de 95% y sólo un 2 a 5% de resultados falsos negativos. Otras indicaciones de la cintigrafía ósea se encuentran en las osteomielitis; enfermedades óseas metabólicas; enfermedad de Paget; artritis y atrosis

Radioinmunodetección tumoral en un paciente portador de una neoplasia colorrectal: descripción del método / Tumoral radioimmunodetection in a patient with a colorectal neoplasm: description of the method

Se presentan los resultados de la aplicación de un método de detección de tumores "in vivo" mediante anticuerpos marcados con radioisótopos, en un paciente portador de un tumor colorrectal. Para ello se utilizan anticuerpos anti-CEA-I131. Se describe la técnica del procedimiento y se efectúa una revisión de la literatura pertinente. Se señala que el caso comunicado es el primero en el que se aplica la radioinmunodetección en nuestro medio