PET/TC con FAPI: procedimiento y revisión de la evidencia en oncología / PET/CT FAPI: Procedure and evidence review in oncology

Las neoplasias se componen de células malignas tumorales que se encuentran rodeadas de diversos elementos celulares no tumorales, que conforman el microambiente o estroma tumoral. La evidencia sobre la importancia este último no ha parado de crecer en los últimos años ya que desempeña un papel necesario para la proliferación celular, la invasión tisular, la angiogénesis y la migración celular. El paradigma es la familia de los nuevos radiofármacos inhibidores de la proteína de activación de fibroblastos (FAPI) que nos muestran la densidad de dicha proteína (FAP) que se encuentra sobreexpresada en la membrana celular de los fibroblastos activados asociados al cáncer (CAF), y su presencia está relacionada con un mal pronóstico. En este documento de formación continuada se incluye el procedimiento para la realización de la tomografía por emisión de positrones/tomografía computarizada (PET/TC) con FAPI, la biodistribución y las potenciales aplicaciones clínicas en oncología publicadas hasta el momento. (AU)

Neoplasms are composed of malignant tumour cells, which are surrounded by other non-tumour cellular elements, what has been defined as the microenvironment or tumour stroma. Evidence on the importance of the tumour microenvironment has not stopped growing in recent years. It plays a central role for cell proliferation, tissue invasion, angiogenesis and cell migration. The paradigm is the family of new FAPI radiopharmaceuticals that show us the density of the fibroblast activation protein (FAP) that is overexpressed in the cell membrane of activated cancer-associated fibroblasts (CAF), and its presence is related to poor prognosis. The paradigm is the family of new FAPI radiopharmaceuticals, which represents the density of activated fibroblasts associated with cancer. This educational document includes the procedure for performing PET/CT FAPI, biodistribution and the main potentially clinical applications in oncology to date. (AU)

PET/CT FAPI: Procedure and evidence review in oncology.

Neoplasms are composed of malignant tumor cells, which are surrounded by other non-tumor cellular elements, in what has been defined as the microenvironment or tumor stroma. Evidence on the importance of the tumor microenvironment has not stopped growing in recent years. It plays a central role in cell proliferation, tissue invasion, angiogenesis and cell migration. The paradigm is the family of new FAPI radiopharmaceuticals that show the density of the fibroblast activation protein (FAP) which is overexpressed in the cell membrane of activated cancer-associated fibroblasts (CAF), and its presence is related to poor prognosis. This educational document includes the procedure for performing PET/CT FAPI, biodistribution and the main potentially clinical applications in oncology to date.

Cirugía y radioembolización de tumores hepáticos / Surgery and radioembolization of liver tumors

La resección quirúrgica se considera el tratamiento curativo por excelencia para los pacientes con tumores hepáticos primarios o metastásicos. Sin embargo, menos de 40% de ellos son candidatos a cirugía, ya sea por factores no modificables (comorbilidades, edad, disfunción hepática…), como por la invasión o proximidad del tumor a los principales pedículos vasculares, la falta de un futuro remanente hepático (FRH) adecuado para mantener una función hepática postoperatoria, o criterios de tamaño y numero tumoral. En estos últimos factores, la radioembolización hepática ha mostrado tener un papel como herramienta prequirúrgica, ya sea mediante la hipertrofia del FRH o mediante la reducción del tamaño tumoral que consigue disminuir la estadificación tumoral (término conocido como «downstaging»). A estos se suma un tercer factor, que es su capacidad de aplicar el test del tiempo, que permite identificar aquellos pacientes que presenten en un plazo corto de tiempo progresión de la enfermedad (tanto a nivel local como a distancia), evitándoles una cirugía innecesaria. En este trabajo se pretende hacer una revisión de la radioembolización como herramienta facilitadora de la cirugía hepática, tanto a través de la experiencia de nuestro centro como de la evidencia científica disponible (AU)

Surgical resection is considered the curative treatment par excellence for patients with primary or metastatic liver tumors. However, less than 40% of them are candidates for surgery, either due to non-modifiable factors (comorbidities, age, liver dysfunction...), or to the invasion or proximity of the tumor to the main vascular requirements, the lack of a future liver remnant (FLR) adequate to maintain postoperative liver function, or criteria of tumor size and number. In these last factors, hepatic radioembolization has been shown to play a role as a presurgical tool, either by hypertrophy of the FLR or by reducing tumor size that manages to reduce tumor staging (term known as “downstaging”). To these is added a third factor, which is its ability to apply the test of time, which makes it possible to identify those patients who present progression of the disease in a short period of time (both locally and at distance), avoiding a unnecessary surgery. This paper aims to review RE as a tool to facilitate liver surgery, both through the experience of our center and the available scientific evidence (AU)

Utilidad de los radioligandos PSMA en el diagnóstico y tratamiento del carcinoma de próstata / The role of PSMA radioligands in the diagnosis and treatment of prostate carcinoma

El cáncer de próstata (CP) es el tumor más frecuente en varones en Occidente y la quinta causa de muerte relacionada con el cáncer. El uso de radioligandos antígeno prostático específico de membrana (PSMA) ha supuesto un importante avance tanto en su diagnóstico, a través de la imagen molecular de tomografía por emisión de positrones (PET), como en su tratamiento en fases avanzadas de la enfermedad. En este artículo, se hace una revisión de la aportación de los estudios PET con radioligandos PSMA en la estadificación inicial, en la detección tumoral en la recidiva bioquímica (elevación del antígeno prostático específico [PSA]) tras un tratamiento con intención curativa, y en los estadios más avanzados de la enfermedad (CP resistente a la castración o CPRC). Se analiza, además, la aportación de la terapia con radioligandos PSMA (PSMA-TRL) en pacientes con CPRC que progresan a la terapia estándar (AU)

Prostate cancer (PC) is the most common tumor in men in the West and the fifth leading cause of cancer-related death. The use of prostate-specific membrane antigen (PSMA) radioligands has represented an important advance in both in the diagnosis by positron emission tomography (PET) molecular imaging and the treatment of advanced stages of the disease. This article reviews the contribution of PET studies with PSMA radioligands in the initial staging, tumor detection in biochemical recurrence (elevation of PSA) after treatment with curative intent, and in the more advanced stages of the disease (castration-resistant PC [CRPC]). The contribution of PSMA radioligand therapy in CRPC patients who progress to standard therapy is also analyzed (AU)

The role of PSMA radioligands in the diagnosis and treatment of prostate carcinoma.

Prostate cancer (PC) is the most common tumor in men in the West and the fifth leading cause of cancer-related death. The use of PSMA radioligands has represented an important advance both in its diagnosis, through PET molecular imaging, and in its treatment in advanced stages of the disease. This article reviews the contribution of PET studies with PSMA radioligands in initial staging, in tumor detection in biochemical recurrence (elevation of PSA) after treatment with curative intent, and in the more advanced stages of the disease (castration resistant PC or CRPC). The contribution of PSMA radioligand therapy (PSMA-RLT) in CRPC patients who progress to standard therapy is also analyzed.

Diagnóstico incidental de tumor neuroendocrino con 68Ga-PSMA PET/TC: a propósito de un caso / Incidental diagnosis of neuroendocrine tumour with 68Ga-PSMA PET/CT: report of clinical case

No disponible

FDG PET/TC en el cáncer colorrectal / FDG PET/CT in colorectal cancer

El cáncer colorrectal es el tercer cáncer en frecuencia a nivel mundial. Aunque su incidencia está aumentando, fundamentalmente en menores de 50 años, su mortalidad ha disminuido un 50% en los países más desarrollados, principalmente debido a la adopción de nuevas prácticas en la prevención, diagnóstico y tratamiento. En particular, las diversas modalidades de diagnóstico por imagen permiten mejorar la toma de decisiones terapéuticas, la evaluación de la respuesta y la eficacia de las nuevas terapias y la detección precoz de la recidiva. La finalidad del presente trabajo es hacer una revisión de la evidencia científica disponible sobre el valor de la tomografía por emisión de positrones con 18F-FDG (18F-FDG PET/TC) en el cáncer colorrectal, haciendo especial hincapié en las indicaciones de las guías y recomendaciones de las principales asociaciones científicas internacionales respecto a esta técnica de imagen

Colorectal cancer is the third most frequent cancer worldwide. Although its incidence is increasing, mainly in those aged under 50, mortality has decreased by 50% in the more developed countries, principally due to the adoption of new practices in prevention, diagnosis and treatment. In particular, the various diagnostic imaging modalities allow improved therapeutic decision-making, evaluation of the response and early detection of recurrence. The aim of this paper is to review the available scientific evidence on the value of positron emission tomography with 18F-FDG (18F-FDG PET/CT) in the colorectal cancer, with special emphasis on the indications of the guidelines and recommendations of the main international scientific associations regarding this imaging technique

Hepatic Flow Redistribution is Feasible in Patients with Hepatic Malignancies Undergoing Same-Day Work-Up Angiography and Yttrium-90 Microsphere Radioembolization.

PURPOSE: To assess the feasibility of performing same-day vascular flow redistribution and Yttrium-90 radioembolization (90Y-RE) for hepatic malignancies. MATERIALS AND METHODS: From November 2015 to February 2019, patients undergoing same-day hepatic flow redistribution during work-up angiography, 99mTechnetium-labeled macroaggregated albumin (99mTc-MAA) SPECT/CT and 90Y microsphere-RE, were recruited. Within 18 h following the delivery of 90Y resin microspheres, an 90Y-PET/CT study was performed. According to patients' vascular anatomy, flow redistribution was performed by microcoil embolization of extrahepatic branches (group A), intrahepatic non-tumoral vessels (group B) and intrahepatic tumoral arteries (group C). The accumulation of 99mTc-MAA particles and microspheres in the redistributed areas was qualitatively evaluated using a 5-point visual scale (grade 1 = < 25% accumulation; grade 5 = 100% accumulation). Differences in the distribution of microspheres among groups were assessed with Mann-Whitney U test. RESULTS: Twenty-two patients were treated for primary (n = 17) and secondary (n = 5) hepatic malignancies. The MAA-SPECT/CT showed uptake in all the redistributed areas. Regarding the accumulation of microspheres within the redistributed segments in all the groups, perfusion patterns were classified as 2 in 1 case, 4 in 6 cases and 5 in 15 cases. No statistically significant differences were observed between groups A and B-C (U value = 34, p = 0.32) and between groups B and C (U value = 26, p = 0.7). Mean predicted absorbed doses by the tumoral and normal hepatic tissues were 163.5 ± 131.2 Gy and 60.4 ± 69.3 Gy, respectively. Mean total procedure time (from work-up angiography to 90Y delivery) was 401 ± 0.055 min. CONCLUSION: Performing same-day redistribution of the arterial hepatic flow to the target and 90Y-microsphere delivery is feasible in the treatment of liver tumors. Clinical Trials Registry NCT03380130.

FDG PET/CT in colorectal cancer. / FDG PET/TC en el cáncer colorrectal.

Colorectal cancer is the third most frequent cancer worldwide. Although its incidence is increasing, mainly in those aged under50, mortality has decreased by 50% in the more developed countries, principally due to the adoption of new practices in prevention, diagnosis and treatment. In particular, the various diagnostic imaging modalities allow improved therapeutic decision-making, evaluation of the response and early detection of recurrence. The aim of this paper is to review the available scientific evidence on the value of positron emission tomography with 18F-FDG (18F-FDG PET/CT) in the colorectal cancer, with special emphasis on the indications of the guidelines and recommendations of the main international scientific associations regarding this imaging technique.

Evolución de la Medicina Nuclear en el diagnóstico y tratamiento de pacientes con cáncer de próstata / Evolution of Nuclear Medicine in the diagnosis and treatment of prostate cancer

No disponible

Radioembolización de tumores hepáticos con 90Y-microesferas / Radioembolization with 90Y-microspheres for liver tumors

No disponible

Aportación del tiempo de vuelo y de la modelización de la respuesta a una fuente puntual a las características de funcionamiento del tomógrafo PET/TAC Biograph mCT / Contribution of time of flight and point spread function modeling to the performance characteristics of the PET/CT Biograph mCT scanner

Objetivo. Caracterizar el funcionamiento del tomógrafo PET/TAC Biograph mCT TrueV que incorpora el tiempo de vuelo (TOF) y modeliza la respuesta a una fuente puntual (PSF). Material y métodos. El tomógrafo combina un TAC de 64 cortes y un PET que reconstruye tomográficamente con TOF y PSF. Las características de funcionamiento PET se evaluaron siguiendo el estándar NEMA NU-2-2007, ampliando algunas pruebas. Adicionalmente se evaluaron diferentes algoritmos de reconstrucción y se midieron la radiación intrínseca y la uniformidad tomográfica. Resultados. La resolución espacial (FWHM) a 1 y 10cm del eje fue de 4,4 y 5,3mm, mejorando al introducir la PSF a 2,6 y 2,5mm. La sensibilidad fue de 10,9 y 10,2 kcps/MBq a 0 y 10cm del eje. La fracción de dispersión fue inferior al 34% a bajas concentraciones y la tasa de sucesos equivalentes al ruido (NECR) fue máxima en 182 kcps a 27,8 kBq/mL. La radiación intrínseca produjo 4,42 coincidencias verdaderas por segundo. El coeficiente de variación de la uniformidad del volumen y del sistema fue del 4,7 y 0,8%. La prueba de calidad de imagen mostró mejores resultados al incluir conjuntamente PSF y TOF. Específicamente, la PSF mejoró el contraste de las esferas calientes y la variabilidad del fondo, mientras que el TOF aumentó el contraste de las esferas frías. Conclusiones. El tomógrafo tiene muy buenas características de funcionamiento, además la calidad de la imagen mejora al incorporar la información de la PSF y del TOF en la reconstrucción tomográfic (AU)

Objective. To characterize the performance of the Biograph mCT PET/CT TrueV scanner with time of flight (TOF) and point spread function (PSF) modeling. Material and methods. The PET/CT scanner combines a 64-slice CT and PET scanner that incorporates in the reconstruction the TOF and PSF information. PET operating characteristics were evaluated according to the standard NEMA NU 2-2007, expanding some tests. In addition, different reconstruction algorithms were included, and the intrinsic radiation and tomographic uniformity were also evaluated. Results. The spatial resolution (FWHM) at 1 and 10cm was 4.4 and 5.3mm, improving to 2.6 and 2.5mm when PSF is introduced. Sensitivity was 10.9 and 10.2 Kcps/MBq at 0 and 10cm from the axis. Scatter fraction was less than 34% at low concentrations and the noise equivalent count rate (NECR) was maximal at 27.8 kBq/mL with 182 Kcps, the intrinsic radiation produced a rate of 4.42 true coincidences per second. Coefficient of variation of the volume and system uniformity were 4.7 and 0.8% respectively. The image quality test showed better results when PSF and TOF were included together. PSF improved the hot spheres contrast and background variability, while TOF improved the cold spheres contrast. Conclusions. The Biograph mCT TrueV scanner has good performance characteristics. The image quality improves when the information from the PSF and the TOF is incorporated in the reconstruction (AU)

[Contribution of time of flight and point spread function modeling to the performance characteristics of the PET/CT Biograph mCT scanner]. / Aportación del tiempo de vuelo y de la modelización de la respuesta a una fuente puntual a las características de funcionamiento del tomógrafo PET/TAC Biograph mCT.

OBJECTIVE: To characterize the performance of the Biograph mCT PET/CT TrueV scanner with time of flight (TOF) and point spread function (PSF) modeling. MATERIAL AND METHODS: The PET/CT scanner combines a 64-slice CT and PET scanner that incorporates in the reconstruction the TOF and PSF information. PET operating characteristics were evaluated according to the standard NEMA NU 2-2007, expanding some tests. In addition, different reconstruction algorithms were included, and the intrinsic radiation and tomographic uniformity were also evaluated. RESULTS: The spatial resolution (FWHM) at 1 and 10cm was 4.4 and 5.3mm, improving to 2.6 and 2.5mm when PSF is introduced. Sensitivity was 10.9 and 10.2 Kcps/MBq at 0 and 10cm from the axis. Scatter fraction was less than 34% at low concentrations and the noise equivalent count rate (NECR) was maximal at 27.8 kBq/mL with 182 Kcps, the intrinsic radiation produced a rate of 4.42 true coincidences per second. Coefficient of variation of the volume and system uniformity were 4.7 and 0.8% respectively. The image quality test showed better results when PSF and TOF were included together. PSF improved the hot spheres contrast and background variability, while TOF improved the cold spheres contrast. CONCLUSIONS: The Biograph mCT TrueV scanner has good performance characteristics. The image quality improves when the information from the PSF and the TOF is incorporated in the reconstruction.