Correlation of 18F-sodium fluoride uptake and radiodensity in extraosseous metastases of medullary thyroid carcinoma

ABSTRACT Objective: Although 18F-sodium fluoride (18F-NaF) uptake is frequently observed in extraosseous metastases of medullary thyroid carcinoma (MTC) with calcification, it can also occur in metastatic sites without visible calcium deposition, leading to the hypothesis that visually undetectable calcium accumulation may be responsible for this uptake. The aim of this study was to indirectly support this hypothesis by analyzing the correlation between the degree of 18F-NaF uptake and radiodensity in extraosseous MTC metastases, since calcium deposition can increase attenuation even when not visually detectable. Subjects and methods: Extraosseous metastatic lesions of 15 patients with MTC were evaluated using 18F-NaF positron-emission tomography (PET)/computed tomography (CT) and segmented by levels of standardized uptake value (SUV). The correlation between mean SUV and mean Hounsfield unit (HU) values was assessed for the entire group of segments and for two subgroups with different mean HU values. Results: Very high correlations were observed between mean SUV and mean HU values for both the entire group of segments and the subgroup with a mean HU value greater than 130 (p = 0.92 and p = 0.95, respectively; p < 0.01). High correlation (p = 0.71) was also observed in the subgroup with mean HU values ranging from 20 to 130 (p < 0.01). Conclusion: The findings of the present study suggest that there is an association between 18F-NaF uptake and calcium deposition in extraosseous metastases of MTC, supporting the hypothesis that visually undetectable calcium accumulation may be responsible for 18F-NaF uptake in regions without visible calcium deposition.

Impacto del PET/CT en el diagnóstico de insulinoma / Impact of PET/CT in the Diagnosis of Insulinoma

Introducción: La tomografía de emisión de positrones es una técnica diagnóstica no invasiva que permite tomar imágenes del organismo que muestra el metabolismo de los órganos del cuerpo. Objetivo: Destacar el valor de la PET/CT en el diagnóstico imagenológico prequirúrgico del enfermo. Presentación de caso: Se presentó un paciente masculino de 39 años sin antecedentes de importancia, con un cuadro de hipoglucemias severas de 5 años de evolución, a pesar de los múltiples estudios imagenológicos se incluyó la ecoendoscopía digestiva, lo que no fue posible evidenciar la lesión tumoral. Se le realiza PET/CT cuyo resultado fue crucial para localizar el tumor, se le dio al paciente la oportunidad de un tratamiento quirúrgico y la demostración anatomopatológica de insulinoma. Conclusiones: Los insulinomas son tumores pancreáticos poco frecuentes que provocan hiperinsulinismo endógeno y son difíciles de visualizar debido a su tamaño por las técnicas de imágenes convencionales, por lo que el PET/CT es un estudio bastante efectivo para localizar la lesión tumoral, y así realizar un procedimiento quirúrgico(AU)

Introduction: Positron emission tomography is a non-invasive diagnostic technique, allowing images of the body to be taken that show the metabolism of the body's organs. Objective: To highlight the value of PET/CT in the pre-surgical imaging diagnosis of the patient. Case presentation: We report the case of a 39-year-old male patient with no significant medical history, but a 5-year history of severe hypoglycemia. Despite multiple imaging studies, digestive ultrasound endoscopy was included, which was not possible to demonstrate the tumor lesion. PET/CT was performed, the result of which was crucial in locating the tumor. The patient was given the opportunity for surgical treatment and the pathological demonstration of insulinoma. Conclusions: Insulinomas are rare pancreatic tumors that cause endogenous hyperinsulinism and are difficult to visualize due to their size using conventional imaging techniques, therefore PET/CT is a fairly effective study to locate the tumor lesion, and thus perform a surgical procedure(AU)

Análisis del manejo del linfoma de Hodgkin clásico durante 10 años en el Hospital Clínico Red Salud UC-Christus con énfasis en el uso del PET CT / Decade of Hodgkin lymphoma: PET CT vs biopsy in single Academic Chilean Center

INTRODUCCIÓN: El Linfoma de Hodgkin (LH) es una causa prevalente de morbilidad por Cáncer Hematológico en el mundo y también en nuestro entorno. OBJETIVOS: Mostrar la experiencia de diez años tratando el LH en un centro docente chileno. Adicionalmente, exponer el rendimiento de diagnóstico del PET CT y la Biopsia de Médula Ósea. MATERIAL Y MÉTODOS: Se realiza un estudio de Cohorte retrospectivo para recopilar datos y resultados de los pacientes tratados en nuestro centro. RESULTADOS: Se analizaron 82 pacientes (edad promedio 35 años. Razón entre hombres y mujeres de 1,9:1). La sobrevida libre de progresión de 88,6% y 66,4% para estadios localizados y avanzados respectivamente. El PET como estrategia de etapificación tuvo mejor sensibilidad al comparar con la Biopsia de Médula. CONCLUSIONES: El resultado clínico de los pacientes tratados en este centro docente chileno fueron comparables a la literatura internacional. Adicionalmente, el PET CT evidenció ser una herramienta superior en el diagnóstico y etapificación superior a la biopsia en nuestros pacientes.

INTRODUCTION: Hodgkin Lymphoma (HL) is a prevalent hematological cancer in the world and Chile. OBJECTIVES: Show the experience of 10 years treating HL in a Chilean academic center. Additionally, it exposes the diagnostic performance of PET CT and Bone Marrow Biopsy. MATERIAL AND METHODS: We conducted a retrospective cohort study to collect data and outcomes of patients treated in our center. RESULTS: 82 patients were analyzed (Average age, 35 years old; the ratio between men and women was 1.9:1). Progression-free survival was 88.6% and 66.4% for localized and advanced stages, respectively. PET as a staging strategy had better sensitivity than Marrow Biopsy. CONCLUSIONS: The clinical results of the patients treated in this Chilean teaching center were comparable to the international literature. Additionally, PET CT proved to be a superior tool in diagnosis and staging compared to biopsy in our patients.

Arteritis de Takayasu como hallazgo incidental en un paciente con enfermedad celiaca: la importancia de la tomografía computarizada por emisión de positrones / Takayasu's arteritis as an incidental finding in a patient with celiac disease: the importance of positron emission computed tomography

Resumen Introducción: La arteritis de Takayasu es una vasculitis de grandes vasos que afecta a las arterias elásticas de gran calibre, fundamentalmente la aorta y sus ramas principales. Ocurre frecuentemente en mujeres entre los 20-30 años, por lo que es muy infrecuente en la edad pediátrica. Caso clínico: Se presenta el caso de una paciente de 15 años en seguimiento desde los 9 años por enfermedad celiaca. A los 13 años se detectó anemia de trastornos crónicos, elevación de proteína C reactiva y velocidad de sedimentación globular. La paciente permaneció en todo momento asintomática. Tras descartar otros procesos, se solicitó tomografía computarizada por emisión de positrones (PET-TC), donde se detectaron lesiones compatibles con vasculitis de grandes vasos. La valoración por Cardiología evidenció un aneurisma en coronaria derecha. Se realizó angio-TC, que sugirió arteritis de Takayasu tipo III. Conclusiones: Es frecuente un retraso en el diagnóstico de la arteritis de Takayasu en los pacientes pediátricos. En este caso se encontraron lesiones de la fase II sin la presencia de síntomas correspondientes a la fase I. El PET-TC permitió el diagnóstico de vasculitis, clave para el diagnóstico de la paciente.

Abstract Background: Takayasu arteritis is a large-vessel vasculitis which affects large-caliber elastic arteries, primarily the aorta and its main branches. It mainly affects women between 20-30 years, so it is rare in children. Case report: We describe the case of a 15-year-old female who was followed up since she was 9 years old due to celiac disease. At the age of 13, anaemia of chronic disorders associated to elevated C-reactive protein and erythrocyte sedimentation were detected. The patient remained asymptomatic. After excluding other diseases, we requested a positron emission computed tomography (PET-CT); lesions compatible with large-vessel vasculitis were detected. Cardiology evaluation showed an aneurysm in the right coronary artery. Angio-CT suggested Takayasu type III arteritis. Conclusions: The delay in the diagnosis of Takayasu arteritis in pediatric patients is quite common. In this case, we have found phase II lesions, with no previous phase I symptoms. However, PET-CT allowed the diagnosis of vasculitis, key to the diagnosis of the patient.

Evaluation of patients via colonoscopy who underwent positron emission tomography/computerized tomography due to colon involvement

SUMMARY OBJECTIVE: Fluorodeoxyglucose is not a tumor-specific agent and it can also be involved in benign conditions, which may cause diagnostic confusion. This research aims to elucidate the colonoscopic findings of patients who underwent colonoscopy due to colon involvement in positron emission tomography/computerized tomography. METHODS: A total of 71 patients who underwent colonoscopy due to colonic involvement in positron emission tomography/computerized tomography at SBU Keçiören Training and Research Hospital Gastroenterology Clinic Endoscopy Unit have been analyzed retrospectively. Demographic characteristics of the patients, areas of involvement in positron emission tomography/computerized tomography, and severity have been obtained from the hospital database. RESULTS: The gastrointestinal involvement area of 22.5% (n=16) of the patients was ascending colon, 15.5% (n=11) was sigmoid, 15.5% (n=11) was rectum, 12.7% (n=9) was stomach, 11.3% (n=8) was transverse colon, 8.5% (n=6) was anal canal, 5.6% (n=4) was esophagus, and 5.6% (n=4) was descending colon. The endoscopic findings of 19.7% (n=14) patients were normal, whereas 29.6% (n=21) had polyps, 9.9% (n=7) had cancer, 2.8% (n=2) had an ulcer, 15.5% (n=11) had gastritis, 14.1% (n=10) had hemorrhoids, and 7% (n=5) had colitis. CONCLUSION: Fluorodeoxyglucose-positron emission tomography can detect unexpected distant metastases with high sensitivity because it allows whole-body imaging. Curative resection significantly contributes to the choice of treatment modality in the pre-operative period of colorectal cancer patients with planned surgery.

Consenso colombo-peruano de cáncer de próstata. Lima, Perú, 14 y 15 de abril del 2023 / Colombian-Peruvian Consensus on Prostate Cancer. April 14 and 15, 2023, Lima, Peru

Entre el 14 y 15 de abril del 2023 se realizó la reunión académica organizada por la Sociedad Colombiana de Urología y la Sociedad Peruana de Urología en Lima (Perú), donde los panelistas expertos en cáncer de próstata en el área de urología oncológica, urología funcional, oncología clínica, radioterapia oncológica y medicina nuclear debatieron sobre la evidencia actual en los diferentes escenarios de la enfermedad, logrando el primer Consenso Colombo-Peruano de Cáncer de Próstata.

Between April 14 and 15, 2023, the academic meeting organized by the Colombian Society of Urology and the Peruvian Society of Urology was held in Lima (Peru), where expert panelists in prostate cancer in the area of oncological urology, functional urology, clinical oncology, oncological radiotherapy and nuclear medicine discussed the current evidence in the different scenarios of the disease, achieving the first Colombo-Peruvian Consensus on Prostate Cancer.

What is the effect of tumor diameter, lymph node metastases, and SUVmax value on prognosis in limited-stage small cell lung cancer?

SUMMARY OBJECTIVE: This study was designed to investigate the link between survival and prognostic factors such as tumor size, lymph node metastasis, and metabolic activity detected on positron emission tomography/computed tomography in patients with limited-stage small cell lung carcinoma. METHODS: Patients who were admitted to our hospital with pathological diagnosis of limited-stage small cell lung cancer between January 2015 and December 2019 and were older than 18 years were retrospectively screened. RESULTS: A total of 77 patients, including 10 females and 67 males, were included in the study. While there were 39 patients over 60 years of age, 38 patients were under 60. The ratios of male patients, N stage, multiple lymph nodes, distant metastasis, brain metastasis, and prophylactic cranial irradiation in the deceased patients' group were significantly (p=0.008, p=0.000, p=0.000, p=0.000, p=0.013, p=0.000, respectively) higher than those in the living patients' group. In the univariate model, we observed that gender, smoking, T stage, N stage, multiple lymph nodes, distant metastasis, brain metastasis, liver metastasis, sequential chemotherapy, sequential radiotherapy, concurrent chemoradiotherapy, and prophylactic cranial irradiation had significant effect (p=0.049, p=0.021, p=0.022, p=0.000, p=0.000, p=0.000 p=0.003, p=0.037, p=0.029, p=0.049, p=0.000, respectively) on survival time. In the multivariate model, smoking, N stage, liver metastasis, and prophylactic cranial irradiation demonstrated significant independent effect (p=0.010, p=0.003, p=0.004, p=0.000, respectively) on survival time. CONCLUSION: Our findings provide useful information for better patient management, especially in terms of negative factors on the continuation of survival during and after the treatment of limited-stage small cell lung carcinoma patients.

Estudio preclínico en primate no-humano con [18F]Fluorotimidina. dosimetría y biodistribución / [18F]Fluorothymidine preclinical study in non-human primate. Dosimetry and biodistribution

Resumen En el linfoma Hodgkin, la tomografía por emisión de positrones (PET-TC) forma parte de los nuevos algoritmos diagnósticos y de valoración de respuesta al tratamiento como método eficaz para evaluar supervivencia y pronóstico de la enfermedad, ya sea a través del PET-TC interino con 2-[18F]fluoro- 2-desoxi-D-glucosa, ([18F]FDG), como también del PET-TC al final de la terapéutica. Sin embargo, la [18F]FDG presenta una baja especificidad en linfoma no Hodgkin de grandes células B. Ante la aprobación en nuestro país del radiotrazador 3´-desoxi-3´-[18F]fluorotimidina, [18F]FLT, indicador de proliferación celular de fase S, éste resultaría un prometedor radiofármaco de uso diagnóstico frente a [18F]FDG. Por lo tanto, el objetivo de este estudio fue valorar la utilización de [18F]FLT mediante un modelo animal en primates no humanos Sapajus cay. Se obtuvieron imágenes de cuerpo entero para evaluar la biodistribución y realizar un cálculo dosimétrico en la médula ósea, dado que este es un órgano crítico por la permanencia del radiofármaco. Para órganos de inte rés, se trazaron curvas de actividad en función del tiempo y se calculó la actividad acumulada normalizada. La dosis media absorbida en la médula ósea se determinó aplicando el esquema conocido como Medical Internal Radiation Dosimetry (MIRD). La dosis media obtenida en el modelo animal por unidad de actividad administrada fue de 8.7 μGy/MBq. Este resultado se extrapoló a un modelo humano adulto resultando en 32 μGy/MBq, de lo que se desprende que PET-TC con [18F]FLT es una herramienta segura para uso diagnóstico y de seguimiento en pacientes con enfermedad oncológica linfoproliferativa u otros tumores sólidos.

Abstract Positron emission tomography-computed tomography (PET-CT) is part of the new diagnostic and therapeutic algorithms for Hodgkin lymphoma. PET-CT is a valuable tool for the assessment of treatment response and prognosis, both by means of interim PET-CT with 2-[ 18F]fluoro-2-deoxy-D-glucose ([18F]FDG) as well as end of treatment (EOT) PET-CT. Given the low specificity of [ 18F]FDG for the diffuse large B cell lymphoma (DLBCL), there is an emerging need for a more specific radiopharmaceutical agent. The recent approval of the radiotracer 3´-deoxy-[18F]-3´-flourothymidine ([18F]FLT), a phase-S mitosis cell proliferation marker, for clinical application in our country, shows as a promising radiopharmaceutical for diagnostic use with incremental value over [18F]FDG. In this study, non-human primates (Sapajus cay) were studied. PET-CT study was performed after the injection of [18F]FLT. Whole-body images were obtained to evaluate the biodistribution and to calculate the dosimetry of bone marrow, as this is a critic organ to this radiotracer. Time-activity curves were traced, normalized activity uptake of the organs of interest were calculated, and mean absorbed dose was also calculated using the established Medical Internal Radiation Dosimetry (MIRD) scheme. The mean dose obtained in the animal model per unit of activity administered was 8.7 μGy/MBq. This result was extrapolated to an adult human model resulting in 32 μGy/MBq, thereby suggesting that [18F]FLT is a secure diagnostic tool to be used on the tracing of patients with DLBCL.

Correlation of PET-CT, MRI and histopathology findings in the follow-up of patients with nasopharyngeal cancer / Correlação dos achados de PET-CT, RM e histopatologia no seguimento de pacientes com carcinoma nasofaríngeo

Abstract Introduction: Surgical treatment options are limited for nasopharyngeal cancer for many reasons including epidemiological and histological properties, proximity to important structures, heavy lymphatic drainage, and the difficulty in ensuring a safe surgical margin; therefore primary treatment is generally radiotherapy and chemotherapy. With current radiotherapy technology, oncological success has been increased and the quality of life of patients during the postradiotherapy period is improved. Objective: The role of magnetic resonance imaging and positron emission-computed tomography in the follow-up of recurrent nasopharyngeal cancer patients who were initially treated with radiotherapy was evaluated with respect to histopathological findings. Methods: A total of 110 patients with nasopharyngeal cancer who had received radiotherapy were included in the study. Patients who were suspected to have recurrence according to endoscopic nasopharyngeal examination and magnetic resonance imaging findings were requested to undergo positron emission-computed tomography. Biopsies were taken from 40 patients who had suspicious lesions in positron emission-computed tomography images. These patients' age, gender, presence/absence of contrast enhancement on magnetic resonance imaging, the SuvMax values of nasopharyngeal and neck lesions, T/N phases at initial diagnosis, histopathological recurrence, and history of neck dissection were assessed. Results: Recurrence was observed in 8 patients (20.0%). Among these, 4 (10.0%) had recurrence at the nasopharynx and 4 (10.0%) at the neck. Patients with recurrence were found to be of older age, male gender, advanced T/N phase, contrast enhancement on magnetic resonance imaging, and higher nasopharyngeal and neck SuvMax values in positron emission-computed tomography. However, these differences were not statistically significant. Only the history of neck dissection was significantly more common among those with recurrence (p < 0.001). However, in multivariate analysis, those with a nasopharyngeal SuvMax value higher than 4.58 were found to have 7.667-fold higher risk for recurrence (p = 0.036). Conclusions: Magnetic resonance imaging and positron emission-computed tomography should be evaluated together in the follow-up of nasopharyngeal cancer. Patients with minimal SuvMax 4.58 on positron emission-computed tomography after contrast enhancement in the T2 sequence on magnetic resonance imaging may considered appropriate for biopsy. Biopsies in patients with a SuvMax value lower than 4.58 can be avoided. Thus, patients avoid surgical stress and unnecessary costs.

Resumo Introdução: As opções de tratamento cirúrgico são limitadas para o carcinoma nasofaríngeo por várias razões, inclusive aspectos epidemiológicos e histológicos, proximidade de estruturas importantes, drenagem linfática carregada e dificuldade de garantir uma margem cirúrgica segura; portanto, o tratamento primário é geralmente radioterapia e quimioterapia. Com a tecnologia atual de radioterapia, o sucesso oncológico aumentou e a qualidade de vida dos pacientes durante o período pós-radioterapia é garantida. Objetivo: O papel da ressonância magnética e da tomografia computadorizada por emissão de pósitrons no seguimento de pacientes com carcinoma nasofaríngeo recorrente, inicialmente tratados com radioterapia, foi avaliado em relação aos achados histopatológicos. Método: Foram incluídos no estudo 110 pacientes com carcinoma nasofaríngeo que receberam radioterapia. Pacientes com suspeita de recorrência de acordo com o exame endoscópico nasofaríngeo e com achados de ressonância magnética foram solicitados a fazer tomografia computadorizada por emissão de pósitrons. Foram feitas biópsias de 40 pacientes com lesões suspeitas nas imagens de tomografia computadorizada por emissão de pósitrons. Os pacientes foram avaliados segundo idade, sexo, presença/ausência de realce por contraste na ressonância magnética, valores SUVmax de lesões nasofaríngeas e cervicais, estágios T/N no diagnóstico inicial, recorrência histopatológica e histórico de esvaziamento cervical. Resultados: A recorrência foi observada em 8 pacientes (20,0%). Entre esses, 4 (10,0%) apresentaram recorrência na nasofaringe e 4 (10,0%) no pescoço. Pacientes com recorrência eram do sexo masculino, apresentavam idade mais avançada, estágio avançado T/N, realce por contraste na ressonância magnética e maiores valores de SuvMax nasofaríngeo e cervical na tomografia computadorizada por emissão de pósitrons. Entretanto, essas diferenças não foram estatisticamente significantes. Apenas o histórico de esvaziamento cervical foi significantemente mais comum entre aqueles com recorrência (p < 0,001). No entanto, na análise multivariada, aqueles com um valor de SUVmax nasofaríngeo superior a 4,58 apresentaram um risco 7,667 vezes maior de recorrência (p = 0,036). Conclusão A ressonância magnética e a tomografia computadorizada por emissão de pósitrons devem ser avaliadas em conjunto no seguimento da doença. Pacientes com valor de SUVmax mínimo de 4,58 na tomografia computadorizada por emissão de pósitrons após realce com contraste na sequência T2 na ressonância magnética podem ser considerados mais adequados para biópsia. Biópsias em pacientes com um valor de SUVmax menor do que 4,58 podem ser evitadas. Dessa forma, podemos evitar o estresse cirúrgico para o paciente e custos desnecessários.

Prognostic value of 18F-FDG PET/CT parameters and histopathologic variables in head and neck cancer / Valor prognóstico de parâmetros de PET/TC com 18F-FDG e variáveis histopatológicas em câncer de cabeça e pescoço

Abstract Introduction 18F-fluorodeoxyglucose positron emission tomography/computed tomography parameters such as; maximum standardized uptake values, standard metabolic tumor volume and otal lesion glycosis are important prognostic biomarkers in cancers. Objective To investigate the prognostic value of these parameters in patients with head and neck cancers. Methods We performed a retrospective study including 47 patients with head and neck cancer who underwent18F-fluorodeoxyglucose positron emission tomography/computed tomography prior to treatment. Standard metabolic tumor volume, otal lesion glycosis and standardized uptake were measured for each patient. The prognostic value of quantitative 18F-fluorodeoxyglucose positron emission tomography/computed tomography parameters and clinicopathologic variables on disease free survival and overall survival were analyzed. Results The median (range) standard metabolic tumor volume and otal lesion glycosis and standardized uptake were 7.63 cm3 (0.6-34.3), 68.9 g (2.58-524.5 g), 13.89 (4.89-33.03 g/mL), respectively. Lymph node metastases and tumour differentiation were significant variables for disease free survival and overall survival, however, all 18F-fluorodeoxyglucose positron emission tomography/computed tomography parameters were not associated with disease- free survival and overall survival. Conclusion Pretreatment quantities positron emission tomography parameters did not predict survival in head and neck cancer.

Resumo Introdução Os parâmetros da tomografia por emissão de pósitrons/tomografia computadorizada com 18F-fluordesoxiglicose, como os máximos valores de captação padronizados, o volume metabólico tumoral padrão e a glicólise total da lesão são importantes biomarcadores prognósticos de câncer. Objetivo Investigar o valor prognóstico desses parâmetros em pacientes com câncer de cabeça e pescoço. Método Fizemos um estudo retrospectivo que incluiu 47 pacientes com câncer de cabeça e pescoço e que foram submetidos à tomografia por emissão de pósitrons/tomografia computadorizada com 18F-fluordesoxiglicose antes do tratamento. Volume metabólico tumoral, glicólise total da lesão e valores de captação padronizados foram aferidos em cada paciente. O valor prognóstico de parâmetros quantitativos da tomografia por emissão de pósitrons/tomografia computadorizada com 18F-fluordesoxiglicose e das variáveis clínico-patológicas sobre a sobrevida livre de doença e a sobrevida geral foi analisado. Resultados A média (intervalo) de volume metabólico tumoral e glicólise total da lesão e valores de captação padronizados foram 7,63 cm3 (0,6-34,3), 68,9 g (2,58-524,5) e 13,89 g/mL (4,89-33,03), respectivamente. Metástase nos nódulos linfáticos e diferenciação tumoral foram variáveis significativas de sobrevida livre de doença e sobrevida geral; contudo, nenhum parâmetro da tomografia por emissão de pósitrons/tomografia computadorizada com 18F-fluordesoxiglicose estava associado a sobrevida livre de doença e sobrevida geral. Conclusão As quantidades dos parâmetros da tomografia por emissão de pósitrons pré-tratamento não previram a sobrevida em câncer de cabeça e pescoço.

Hipoglucemia hiperinsulinémica congénita persistente, reporte de un caso / Persistent congenital hyperinsulinemic hypoglucemia, case report

Resumen La placenta y el hígado son los encargados del metabolismo de los carbohidratos. La glucosa es fundamental para el metabolismo cerebral. La hipoglucemia se define con valores < 47 mg/dl. La hipoglicemia que persiste más de 7 días se atribuye a problemas metabólicos o endocrinológicos y requiere un flujo de glucosa > 12 mg/kg/min para alcanzar normo-glicemia. La hipoglicemia hiperinsulinémica congénita persistente (HHCP) es poco común (1:50,000 nacidos vivos), es la causa más común de hipoglicemia persistente secundaria a una secreción inadecuada de insulina, que puede afectar el neurodesarrollo. Hay una forma difusa y una focal, con manifestaciones clínicas idénticas, pero con mecanismos patológicos diferentes. El tratamiento médico es a base de diazóxido y ocreótide. En el 95% de los casos no hay respuesta al tratamiento médico, requiriendo pancreatectomía subtotal. Se utilizó ocreótide y nifedipino. La tomografía computada con emisión de positrones (PET/TC 18F-DOPA) encontró incremento en la capación pancreática de insulina, se realizó pancreactectomía. Se egresó sin complicaciones y en seguimiento pediátrico sin alteraciones neurológicas.

Abstract The placenta and liver are responsible for the metabolism of carbohydrates. The glucose is fundamental for brain metabolism. Hypoglycaemia is defined as values < 47 mg/dl. Hypoglycaemia that persists for more than 7 days is attributed to metabolic or endocrine problems and requires glucose flow > 12 GKM to reach normoglycemia. Persistent congenital hyperinsulinemic hypoglycemia (PCHH) is uncommon (1:50,000 live births) is the most common cause of persistent hypoglycemia secondary to inadequate insulin secretion, can significantly affect neurodevelopment. There is a diffuse and a focal form, with identical clinical manifestations, but with different pathological mechanisms. The medical treatment is diazoxide and ocreotide. In 95% of cases there is no response to medical treatment, requiring subtotal pancreatectomy. Ocreotide and nifedipine were used. Positron emission computed tomography (PET/CT 18F-DOPA) found an increase in pancreatic insulin capacity, a pancreactectomy was performed. He was discharged without complications and in pediatric follow-up without neurological alterations.

Imágenes en endocarditis infecciosa: no todo es ecocardiografía / Imaging in infective endocarditis: not all is ultrasonography

Resumen La endocarditis infecciosa (EI) es una enfermedad de alta mortalidad, caracterizada por una infección endocárdica y frecuentes complicaciones multiorgánicas, que requiere un diagnóstico rápido y preciso, y un manejo agresivo, ya sea médico o quirúrgico. Su diagnóstico se realiza tomando en cuenta criterios bacteriológicos, clínicos y ecocardiográficos. Es objetivo de este artículo realizar una actualización del estudio imagenológico en paciente con EI, con especial énfasis en aquellos exámenes no ecocardiográficos disponibles en nuestro medio. En los últimos años, estudios de imagen avanzados han adquirido un rol creciente en su estudio inicial, particularmente la tomografía computada multicorte (TCMC) cardiaca y el positron emission tomography/computed tomography (PET/CT), y han sido recomendados como criterios diagnósticos en las guías recientes para el manejo de esta entidad. La TCMC cardiaca proporciona información anatómica detallada de las válvulas cardiacas y tejido perivalvular, identificando pseudoaneurismas, abscesos y dehiscencias valvulares. El PET/CT con F18-fluorodeoxiglucosa (F18-FDG) permite aumentar la sensibilidad en la detección de EI, y pesquisar con alta eficiencia fenómenos embólicos sistémicos, de elevada frecuencia en esta población. Ambos métodos prestan particular utilidad en EI de válvula protésica, donde la ecocardiografía presenta menor rendimiento diagnóstico. La resonancia magnética (RM) cerebral es el mejor método de imagen para descartar eventos isquémicos/embólicos del sistema nervioso central.

Abstract Infective endocarditis (IE) is an entity characterized by endocardial infection and frequent multiorgan complications, resulting in high mortality. It requires a rapid and accurate diagnosis, and a medical or surgical aggressive treatment. Currently, IE diagnosis rests on bacterial, clinical and ultrasonographic criteria. The objective of this article is to update the imaging study in patients with IE, with special emphasis on those non-echocardiographic examinations available in our environment. Last years, advanced imaging had achieved a growing role in IE diagnosis, especially cardiac multislice computed tomography (MSCT) and positron emission tomography/computed tomography (PET/CT), which have been recommended in recent clinical guidelines to be included as part of diagnostic criteria. Cardiac MSCT provides detailed anatomic information of cardiac valves and perivalve tissue, allowing identification of pseudoaneurysm, abscess and valve dehiscence. F18-FDG PET/CT increases sensitivity for IE detection and shows high accuracy in searching for extracranial systemic embolic events. Both MSCT and PET/CT have particular utility in cases of prosthetic valve endocarditis, where cardiac ultrasonography shows lower performance. Brain magnetic resonance imaging (MRI) is the best imaging method for evaluating ischemic/embolic events of central nervous system.

Retos de la medicina nuclear ante la pandemia de COVID-19 / Challenges of nuclear medicine in the face of the COVID-19 pandemic

Introducción: En diciembre 2019 emergió una nueva enfermedad, la COVID-19, hasta ser declarada por la Organización Mundial de la Salud como pandemia. Internacionalmente se han publicado artículos y guías útiles para la protección del personal y guías de actuación en los Servicios de Medicina Nuclear para la práctica de exploraciones o tratamientos a pacientes positivos al SARS CoV-2 o altamente sospechosos. Objetivo: Analizar las experiencias y recomendaciones para los Servicios de Medicina Nuclear de diferentes grupos de trabajo ante los retos que plantea mantener la asistencia médica en tiempos de COVID-19 e identificar cuáles son las que podrían aplicarse en Cuba. Métodos: Se realizó una revisión bibliográfica, en español e inglés, de publicaciones en el transcurso de este año. Se utilizaron los motores de búsqueda de Google, Google Académico y Pubmed. Se recolectó y organizó toda la información de las recomendaciones y guías para el trabajo de los Servicios de Medicina Nuclear en la etapa pandémica de la COVID-19 y los hallazgos encontrados en estudios de medicina nuclear en pacientes asintomáticos, que muestran imágenes morfológicas y funcionales características de la neumonía causada por COVID-19. Análisis y síntesis de la información: Se analizaron las diferentes medidas que han propuesto grupos de trabajo en Asia, Europa y América del Norte, se identificaron las más relevantes y se evidenció que son también las que coinciden en casi todas las recomendaciones. Conclusiones: Se propone qué medidas generales podrían adoptarse en los Servicios de Medicina Nuclear cubanos en el contexto de la pandemia de COVID-19(AU)

Introduction: In December 2019, a new disease emerged, COVID-19, until it was declared by the World Health Organization as a pandemic. Articles and useful guides have been published internationally for the protection of personnel and guidelines for action in the Nuclear Medicine Services for the practice of examinations or treatments for patients who are positive for SARS CoV-2 or highly suspicious. Objective: To analyze the experiences and recommendations for the Nuclear Medicine Services of different working groups in the face of the challenges posed by maintaining medical care in times of COVID-19 and to identify which ones could be applied in our country. Methods: A bibliographic review was carried out, in Spanish and English, of publications in the course of this year. The search engines Google, Google Scholar and Pubmed were used. All the information on the recommendations and guidelines for the work of the Nuclear Medicine Services in the pandemic stage of COVID-19 and the findings found in nuclear medicine studies in asymptomatic patients, showing morphological and functional images characteristic of the pneumonia caused by COVID-19, was collected and organized. Analysis and synthesis of the information: The different measures proposed by working groups in Asia, Europe and North America were analyzed, the most relevant were identified and it was shown that they are also the ones that coincide in almost all the recommendations. Conclusions: It is proposed what general measures could be adopted in Cuban Nuclear Medicine Services in the context of the COVID-19 pandemic(AU)

Prognostic role of 18F-FDG PET-CT in the prone position in the evaluation of invasive breast carcinoma

Introduction: The objective of this study was to correlate the features of invasive breast carcinoma in 18F-FDG positron emission tomography/computed tomography with histopathological results, findings from other imaging methods, and survival. Methods: This observational single-center study included patients who underwent staging 18F-FDG positron emission tomography/ computed tomography between September 2012 and April 2019; the results were correlated with the findings of other imaging tests and anatomopathological results. Lesions were evaluated for their maximum standardized uptake value on positron emission tomography/computed tomography performed in the prone position. Tumors were classified into three subtypes (luminal, HER2 and triple-negative) based on immunohistochemical analyses. Results: A total of 125 patients with a mean age of 52 years (24­90 years) were analyzed. The primary tumor showed an increased 18F-FDG concentration on positron emission tomography/computed tomography in 122 (97.6%) patients, with a mean maximum standardized uptake value of 7.15 (1.0­32.9 range). The mean maximum standardized uptake value was higher in the triple-negative subtype (11.4; n=24) than in the luminal (6.2; n=89) and HER2 (5.0; n=9) subtypes (p<0.01). Tumors with more aggressive histological and immunohistochemical characteristics showed higher maximum standardized uptake values. Patients with a standardized uptake value greater than 7 in the primary tumor or greater than 6.7 in the axillary lymph nodes had poor overall survival (p=0.03 and p<0.01, respectively). Conclusions: Our study suggests that the maximum standardized uptake value obtained on positron emission tomography/computed tomography in the prone position may correlate with the tumor immunophenotype and overall survival regardless of the treatments performed, and can be used as a prognostic biomarker in invasive breast carcinoma patients

Recurrent diffuse large B-cell lymphoma mimicking primary breast cancer

Breast lymphoma can represent 0.8%­2.2% of extranodal lymphomas and 0.1%­0.5% of primary breast neoplasms. Imaging findings are not specific, and its distinction from primary invasive breast carcinoma should be based on clinical data and histopathological analysis. We present the case of a 62-year-old woman who showed an unusual pattern of recurrent diffuse large B-cell lymphoma (DLBCL) mimicking primary breast cancer on imaging studies, including mammography, ultrasound, magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT).

PET-CT: Signos radiológicos en el Síndrome Sarcoidosis-Linfoma: Reporte de un caso y revisión / PET-CT: Radiologic signs in Sarcoidosis-Lymphoma Syndrome: Case Reporte and review

El síndrome sarcoidosis-linfoma es una entidad clínica a la cual se puede llegar de distintas formas a su diagnóstico. Algunas de las mismas suelen ser atípicas. Para estos casos complejos, la tomografía por emisión de positrones (PET) combinado con un escáner de tomografía computarizada de rayos X (CT), (PET-CT) es definitorio para llegar posteriormente a la biopsia. Se presenta un caso clínico de nuestro grupo que da lugar a la revisión/puesta al día correspondiente.

Sarcoidosis-lymphoma syndrome is a clinical entity that can be diagnosed in different ways. Some of them are atypical. For these complex cases, positron emission tomography (PET) combined with an X-ray computed tomography (CT) scanner (PET-CT) is definitive for subsequent biopsy. A clinical case of our group is presented, which leads to the corresponding revision/update.

Análisis y selección de técnicas para la fusión de imágenes PET/CT basado en software / Analysis and selection of techniques for the fusion of PET/CT imaging based on software

Técnicas como la Tomografía por Emisión de Positrones y la Tomografía Computarizada permiten determinar la naturaleza maligna o benigna de un tumor y estudiar las estructuras anatómicas del cuerpo con imágenes de alta resolución, respectivamente. Investigadores a nivel internacional han utilizado diferentes técnicas para la fusión de la Tomografía por Emisión de Positrones y la Tomografía Computarizada porque permite observar las funciones metabólicas en correlación con las estructuras anatómicas. La presente investigación se propone realizar un análisis y selección de algoritmos que propicien la fusión de neuroimágenes, basado en la precisión de los mismos. De esta forma contribuir al desarrollo de software para la fusión sin necesidad de adquirir los costosos equipos de adquisición de imágenes de alto rendimiento, los cuales son costosos. Para el estudio se aplicaron los métodos Análisis documental, Histórico lógico e Inductivo deductivo. Se analizaron e identificaron las mejores variantes de algoritmos y técnicas para la fusión según la literatura reportada. A partir del análisis de estas técnicas se identifica como mejor variante el esquema de fusión basado en Wavelet para la fusión de las imágenes. Para el corregistro se propone la interpolación Bicúbica. Como transformada discreta de Wavelet se evidencia el uso de la de Haar. Además, la investigación propició desarrollar el esquema de fusión basado en las técnicas anteriores. A partir del análisis realizado se constataron las aplicaciones y utilidad de las técnicas de fusión como sustitución a los altos costos de adquisición de escáneres multifunción PET/CT para Cuba(AU)

Techniques such as Positron Emission Tomography and Computed Tomography allow to determine the malignant or benign nature of a tumor and to study the anatomical structures of the body with high resolution images, respectively. International researchers have used different techniques for the fusion of Positron Emission Tomography and Computed Tomography because it allows observing metabolic functions in correlation with anatomical structures. The present investigation proposes to carry out an analysis and selection of algorithms that favor the fusion of neuroimaging, based on their precision. In this way, contribute to the development of fusion software without the need to purchase expensive high-performance imaging equipment, which is expensive. For the study the documentary analysis, logical historical and deductive inductive methods were applied. The best algorithm variants and techniques for fusion were analyzed and identified according to the reported literature. From the analysis of these techniques, the Wavelet-based fusion scheme for image fusion is identified as the best variant. Bicubic interpolation is proposed for co-registration. As a discrete Wavelet transform, the use of Haar's is evidenced. In addition, the research led to the development of the fusion scheme based on the previous techniques. From the analysis carried out, the applications and usefulness of fusion techniques were verified as a substitute for the high costs of acquiring PET / CT multifunction scanners for Cuba(AU)

Trastornos del ánimo y demencia: aspectos clínicos y estudios complementarios en el diagnóstico diferencial / Mood disorders and dementia: clinical aspects and complementary studies in the differential diagnosis

Los trastornos del ánimo en el adulto mayor, especialmente aquellos de inicio tardío son difíciles de diferenciar de la demencia en su etapa inicial, dado que existe un traslape sintomático. Esto puede llevar a errar o a retrasar el diagnóstico e impedir la entrega de un tratamiento adecuado. Para el diagnóstico diferencial es fundamental obtener una historia rigurosa tanto del paciente como de la familia, un examen mental y neurológico. Se complementa con un estudio neuropsicológico y con biomarcadores de demencia. Hoy en día se dispone de nuevas técnicas de diagnóstico precoz en la demencia como la volumetría de hipocampos, el PET/CT F18-FDG y PET de amiloide, beta-amiloide y proteína Tau en el LCR, entre otras, que ayudan en casos complejos de diagnóstico diferencial. Este artículo de revisión reúne elementos clínicos y estudios complementarios, con el objetivo de ayudar al psiquiatra en la tarea de diferenciar ambos cuadros.

Mood disorders in the elderly, especially those with late onset are difficult to differentiate from Dementia in its initial stage, given that there is a symptomatic overlap. This can lead to miss or delay the diagnosis and subsequently prevent an appropriate treatment. For the differential diagnosis it is essential to obtain a rigorous history of both the patient and the family, a mental and neurological examination. It is complemented with a neuropsychological assessment and with biomarkers of Dementia. Nowadays, new early diagnosis techniques are available in Dementia such as hippocampal volumetry, PET/CT F18-FDG and PET of amyloid, beta-amyloid and Tau protein in the CSF, among others, which help in complex cases of differential diagnosis. This article reviews clinical elements and complementary studies that help the psychiatrist in the task of differentiating both disorders.

Utilidad de la tomografía por emisión de positrones/ tomografía computada (PET/CT) en pacientes con diagnóstico de meduloblastoma / Usefulness of Positron Emission Tomography/Computed Tomography (PET/CT) in Patients Diagnosed with Medulloblastoma

Resumen: La tomografía por emisión de positrones/tomografía computada (PET/CT) por sus siglas en inglés, es una modalidad de imagen única que proporciona evidencia in vivo de actividades tanto bioquímicas como fisiológicas en diferentes órganos y estructuras del cuerpo. El meduloblastoma es el tumor maligno más frecuente del sistema nervioso central (SNC) en pacientes pediátricos, por este motivo el PET/CT juega un papel importante en el manejo de estos pacientes ya que proporciona información sobre el grado y extensión del tumor, así como a determinar el sitio adecuado para la toma de biopsia, valorar la respuesta al tratamiento y determinar el pronóstico del paciente. Existen diferentes radiofármacos para la evaluación de los tumores de sistema nervioso central, pero se ha estudiado que el 18F-FDG (flúor-2-fluoro-2-desoxi-D-glucosa) y el 68Ga-DOTA-NOC (68Ga-DOTA0-1NaI3-octreotide) nos ayudan a evaluar y dar seguimiento a pacientes con diagnóstico de meduloblastoma. El meduloblastoma tiene una sobreexpresión de transportadores de glucosa, principalmente tipo 1 y sobreexpresión de receptores de somatostatina predominantemente tipo 2, lo cual permite que exista una gran afinidad por estos radiofármacos.

Abstract: PET/CT (positron emission tomography/computed tomography, for its acronym in English) is a unique imaging method that provides in vivo evidence of both biochemical and physiological activities of the brain, spinal cord and tumors that involve these structures. Medulloblastoma is the most common malignant tumor of the central nervous system (CNS) in pediatric patients, so PET/CT plays an important role as it provides information on the grade and extent of the tumor, as well as to determine the appropriate site for the biopsy, assessing the response to the treatment and the patient's prognosis. There are different radiopharmaceuticals for the evaluation of central nervous system tumors, but 18F FDG (Fluor-2-fluoro-2-desoxy-D-glucose) and 68Ga-DOTA-NOC (68Ga-DOTA0-1NaI3-octreotide) have been studied to help us evaluate and follow up patients diagnosed with medulloblastoma. Medulloblastoma has an overexpression of glucose transporters, mainly type 1, and an overexpression of predominantly type 2 somatostatin receptors, which allows a high affinity for these radiopharmaceuticals.

Tomografía por emisión de positrones en el diagnóstico de sarcoidosis y síndrome de Löfgren / Tomography by emission of positrons in the diagnosis of sarcoidosis and Löfgren's syndrome

La sarcoidosis es una enfermedad granulomatosa no caseificante, multisistémica, de causa desconocida, que compromete el pulmón y los ganglios linfáticos mediastinales entre el 90-95 por ciento de los casos. También puede afectar otros órganos como las glándulas salivales, piel, ojos, hígado, bazo, corazón, huesos y sistema nervioso central. El compromiso torácico representa la principal causa de morbilidad con unas 10/100 000 personas al año y mortalidad. Nuestro estudio tuvo como objetivo presentar a un paciente de 45 años de edad atendido por tener manifestaciones clínicas, paraclínicas y radiográficas que permitieron establecer, sin confirmar mediante estudio histológico, el diagnóstico de una forma aguda de sarcoidosis. Su forma clínica de expresión coincidió con el síndrome de Löfgren con ensanchamiento mediastinal bilateral por linfoadenopatía hiliar, síndrome febril, eritema nudoso y artritis aguda en miembros inferiores, que desarrollan entre un 20-30 por ciento de los pacientes con sarcoidosis. Se le realizó una tomografía por emisión de positrones, cuyos resultados ofrecieron elementos diagnósticos propios de un proceso inflamatorio pulmonar alejado de las características propias de una neoplasia maligna. Después de una profunda evaluación del riesgo-beneficio, se impuso tratamiento inmunosupresor con esteroides a dosis elevadas y seguimiento estrecho. Observamos una evolución muy positiva e inmediata desde el punto de vista clínico y radiográfico. Luego de varias semanas de tratamiento se apreciaron los cambios con marcada mejoría hasta pasados 3 meses que constatamos prácticamente una casi desaparición de las imágenes radiográficas(AU)

Sarcoidosis is a multisystemic, non-caseating granulomatous disease of unknown cause that involves the lung and the mediastinal lymph nodes in between 90 percent and 95 percent of cases. It can also affect other organs, such as the salivary glands, skin, eyes, liver, spleen, heart, bones, and central nervous system. Thoracic involvement represents the main cause of morbidity and mortality in patients with this entity, which occurs in about 10 / 100,000 people a year. Our study aimed to present a 45-year-old patient treated for presenting clinical, paraclinical and radiological manifestations that allow the diagnosis of an acute form of sarcoidosis to be established without confirming by histological study. Its clinical form of expression showed the presence of Löfgren's syndrome with bilateral mediastinal widening due to hilar lymphadenopathy, febrile syndrome, erythema nodosum, and acute arthritis in the lower limbs, which 20-30 percent of patients with sarcoidosis develop. A positron emission tomography scan was performed and its results offered us diagnostic elements typical of a pulmonary inflammatory process far from the characteristics of a malignant neoplastic process(AU)