Detección de la infiltración de la cadena mamaria interna en pacientes con cáncer de mama mediante PET/RM con 18F-FDG y sus implicaciones terapéuticas / Detection of internal mammary chain infiltration in breast cancer patients by [18F]FDG PET/MRI: Therapy implications

Objetivo: Evaluar la tasa de detección y la implicación terapéutica de la infiltración de la cadena mamaria interna (ICMI) mediante tomografía por emisión de positrones (PET) y resonancia magnética (RM) con 18F-fluorodesoxiglucosa (18F-PET/RM) en la estadificación de pacientes con cáncer de mama. Método: Estudio prospectivo, 41 mujeres con cáncer de mama (estadio ≥ IIB) estadificadas mediante 18F-FDG-PET/RM. Estudio en dos fases: imágenes mamarias (decúbito prono), cuerpo completo (supino). Estadificación TNM por consenso entre especialista en Medicina Nuclear y Radiología. Estudio vaso aferente (VA) a cadena mamaria interna (CMI) por RM mamaria. Correlación ICMI con edad, VA-CMI, estadificación T, cuadrante, infiltración axilar y a distancia. Revaloración terapéutica en comité multidisciplinar. Resultados: Tasa de detección de ICMN de 34% (14/41), siendo 8/14 < 55 años. Todas las 14 pacientes con ICMI muestran VA-CMI, en seis de ellas (43,9%) sin VA-axilar. De 27/41 sin ICMI, en 13 (48,1%) solo VA-axilar, en los 14 restantes (51,9%) VA-axilar y VA-CMI. Un total de 57% (8/14) son multicéntricos y 42% (6/14) focales, en cuadrantes internos en 4/6 (66,7%). En 1/14 (7,1%) solo ICMI, en 9/14 (64,3%) axilar y CMI y en 4/14 (28,6%) lesiones a distancia. Decisión del comité: sin tratamiento adicional en 27/41 (65,8%), radioterapia torácica en 10/41 (24,4%) y terapia sistémica en 4/41 (9,7%). Conclusión: La tasa de detección de la ICMI en la estadificación del cáncer de mama mediante 18F-FDG PET/RM es de 34%. Son factores asociados la edad, los tumores multicéntricos, los de cuadrantes internos, la existencia de VA-CMI, la estadificación NM. La evidencia de ICMI permite la individualización de la terapia, indicando la radioterapia torácica en 24,4%.(AU)

Objective: To evaluate the detection rate and therapeutic implication of the infiltration of the internal mammary chain (IMCI) by [18F]FDG PET/MRI for staging of patients with breast cancer. Methods: Prospective study including 41 women with breast cancer (stage ≥IIB) staged by [18F]FDG PET/MR. Two-phase exam: breast imaging (prone), whole-body (supine). TNM stage assessed by peer consensus with Nuclear Medicine and Radiology specialists. Study of the afferent vessel (AV) to IMC by breast MRI. IMCI was correlated with age, AV-IMC, T stage, breast quadrants, axillary and distant infiltration. Therapeutic re-evaluation by a multidisciplinary committee. Results: IMCI detection rate of 34% (14/41), with 8/14 patients under 55 years of age. All 14 patients with IMCI showed AV-IMC, 6 of them (43.9%) without VA-axillary. Of 27/41 patients without IMCI, in 13 (48.1%) only AV-axillary was found, in the remaining 14 (51.9%), AV-axillary and AV-IMC was found. In 57% (8/14) tumours were multicentric and 42% (6/14) focal, in inner quadrants in 4/6 (66.7%). In 1/14 patient (7.1%) only IMCI was found, in 9/14 (64.3%) axillary and IMC, in 4/14 patients (28.6%) distant lesions were detected. Committee re-evaluation: no further treatment in 27/41 patients (65.8%), thoracic radiotherapy in 10/41 patients (24.4%), systemic therapy in 4/41 patients (9.7%). Conclusion: Our detection rate of IMCI in breast cancer staging by [18F]FDG PET/MR was 34%. Related factors were age, multicentric tumours, inner quadrants, detection of AV-IMC, NM staging.The evidence of IMCI allowed tailored therapy, with thoracic radiotherapy implementation in 24.4% of patients.(AU)

Concordancia entre SPECT portátil y la gammagrafía convencional para detección de ganglio centinela en cáncer de mama / Concordance between freehand SPECT and conventional scintigraphy for sentinel lymph node detection in breast cancer

Introducción: La SPECT portátil puede ser una técnica de imagen útil para la planificación preoperatoria de la biopsia selectiva del ganglio centinela (BSGC) ya que permite la localización del ganglio centinela (GC) mediante imágenes tomográficas en 3D y en tiempo real y determina su profundidad, después de unos minutos de exploración. El objetivo del estudio fue evaluar la correlación entre el número de GC detectados entre las imágenes de la SPECT portátil y la linfogammagrafía (LG). Materiales y métodos: Cien pacientes con diagnóstico de cáncer de mama infiltrante y sin evidencia clínica de afectación ganglionar, se sometieron prospectivamente a una BSGC. El estudio preoperatorio incluyó imágenes de SPECT portátil a los 15 min tras la inyección y de LG a los 25 y 60-90 min (precoz y tardía). Se analizó el acuerdo observado y se realizó un estudio de concordancia entre el número de GC detectados con SPECT portátil y LG. Resultados: El acuerdo observado en la detección de GC entre SPECT portátil y LG precoz fue del 72%; entre SPECT portátil y LG tardía del 85%, y entre la LG precoz y la tardía de un 87%. En el estudio de concordancia se registró una concordancia moderada entre la SPECT portátil y la LG precoz (coeficiente kappa: 0,42); una concordancia moderada-alta entre la SPECT portátil y la LG tardía (coeficiente kappa: 0,60), y una concordancia de moderada-alta entre la LG precoz y la tardía (coeficiente kappa: 0,70), sin diferencias significativas entre ellos (valor p=0,16). Conclusión: La SPECT portátil presentó una concordancia moderada-alta con los estudios de imagen convencional y podría ser una alternativa válida para el estudio prequirúrgico de la BSGC en el cáncer de mama.(AU)

Introduction: Freehand SPECT can be a useful imaging technique for preoperative planning of sentinel lymph node biopsy (SLNB) as it allows localization of the sentinel node by 3D and real-time tomographic imaging and determines its depth after a few minutes of scanning. The aim of the study was to evaluate the correlation between the number of detected SNs between freehand SPECT images and lymphoscintigraphy (LS). Materials and methods: One hundred patients with a diagnosis of invasive breast cancer and no clinical evidence of lymph node involvement prospectively underwent SLNB. The preoperative study included freehand SPECT imaging at 15min after injection and LS imaging at 25 and 60–90min after injection (early and late). The observed agreement was analyzed and a concordance study was performed between the number of SNs detected with freehand SPECT and LS. Results: The observed agreement in the detection of SNs between freehand SPECT and early LS was 72%; between freehand SPECT and late LS was 85%; and between early and late LS was 87%. In the concordance study, there was moderate concordance between freehand SPECT and early LS (kappa coefficient: 0.42); moderate-high concordance between freehand SPECT and late LS (kappa coefficient: 0.60); and moderate-high concordance between early and late LS (kappa coefficient: 0.70), with no significant differences between them (p-value=0.16). Conclusion: Freehand SPECT showed a moderate-high concordance with conventional imaging studies and could be a valid alternative for the presurgical study of SLNB in breast cancer.(AU)

Papel del radiofarmacéutico clínico en la seguridad del paciente durante los estudios de perfusión miocárdica de esfuerzo con vasodilatadores / Role of the clinical radiopharmacist in patient safety during myocardial perfusion imaging with vasodilator stress agents

Objetivos: Evaluar el papel del radiofarmacéutico en un equipo multidisciplinar en la detección de contraindicaciones del regadenosón para su uso seguro en pacientes a los que se solicitó una SPECT de perfusión miocárdica. Métodos: Se estudió ambispectivamente su uso seguro en 1.905 pacientes (54,1% mujeres, edad media: 66,6±11,7 años, rango: 20-95años). Se registraron datos relativos al sexo, a la edad, al historial médico, a la medicación, a las alergias medicamentosas y a las contraindicaciones para el estrés farmacológico, así como las recomendaciones realizadas al médico nuclear responsable. Resultados: Las contraindicaciones detectadas y las correspondientes recomendaciones fueron las siguientes: riesgo de prolongación del intervalo QTc (7,5%): comprobación previa del intervalo QTc y monitorización del ECG; ictus o AIT previo (4,2%): evaluación de estenosis carotídea; alergia a salicilatos y/o sulfamidas (3,1%): empleo de [99mTc]Tc-MIBI; epilepsia o riesgo de convulsiones (2,4%): uso de adenosina o reconsiderar su indicación; tratamiento con corticosteroides sistémicos en EPOC severa (1,3%): reevaluar las condiciones del paciente; EPOC reagudizada (0,8%): posponer hasta la resolución del episodio agudo; asma grave (0,4%): no realizar la prueba; toma de metilxantinas (0,3%): evitar su consumo previo; otras (6,1%): evaluación de cada contraindicación. No se observaron contraindicaciones en el 73,6% de los pacientes. Se anularon el 2,9% de las peticiones debido a contraindicaciones absolutas. Conclusiones: Empleando una metodología de trabajo sistemática, el radiofarmacéutico detectó un elevado número de incidencias, presentando uno de cada cuatro pacientes alguna contraindicación clínica. Las recomendaciones emitidas fueron aceptadas por los médicos nucleares, que modificaron su enfoque, incrementando así la seguridad de estos pacientes.(AU)

Aim: To assess the radiopharmacist's role in a multidisciplinary team focused on the contraindications of regadenoson in order to ensure the safe use of pharmacologic vasodilator stress agents in patients undergoing SPECT-MPI. Methods: We ambispectively studied its safe use in 1905 patients (54.1% female, mean age: 66.6±11.7 years, range: 20-95years). Sex, age, medical history, medications, drug allergies, and contraindications for stress testing were registered together with recommendations for the nuclear physician in charge. Results: Detected contraindications and corresponding recommendations were as follows: risk factors for QTc interval prolongation 7.5% — measurement of QTc interval previously to test and monitor ECG; prior stroke or TIA 4.2% — consider carotid stenosis assessment; salicylates/sulfonamides allergy 3.1% — use 99mTc-sestamibi; epilepsy or risk factors for seizures 2.4% — use of adenosine or reconsider test indication; systemic corticosteroid therapy for severe COPD 1.3% — reassessment of patient's condition; acute exacerbation of COPD 0.8% — defer test until acute episode is over; severe asthma 0.4% — do not perform test; methylxanthine ingestion 0.3% — avoid consumption previously; other 6.1% — evaluation of other contraindications. No contraindications were detected in 73.6% of patients. The test was cancelled due to absolute contraindications in 2.9% of the requests. Conclusions: Working in a systematic way, the radiopharmacist was able to detect a high number of issues related to regadenoson, with one out of four patients presenting some clinical contraindication. The recommendations given by the radiopharmacist were well accepted by the nuclear physicians who changed their approach contributing to increase the safety of patients referred for MPI.(AU)

Equipo multidisciplinar de cirugía radioguiada: Alternativa de cambio al paradigma actual / Multidisciplinary radio-guided surgery team: Alternative to change the current paradigm

IntroducciónAnte el aumento constante de la demanda asistencial de exploraciones relacionadas con cirugía radioguiada (CRG), nuestro hospital adoptó incluir en el equipo de CRG nuevos perfiles profesionales con el fin de reducir parcialmente el tiempo de dedicación de los médicos nucleares a esta tarea.Objetivos: Analizar el proceso de incorporación de los perfiles de Técnico Superior en Imagen para el Diagnóstico (TSID) y Enfermera Referente de Ganglio Centinela (ERGC), evaluando su despliegue en los procedimientos ligados a la técnica. Material y métodos: Análisis de la actividad de CRG durante el periodo 2018-2022, centrándolo en los procedimientos prequirúrgicos y quirúrgicos relativos a cáncer de mama (CaM) y melanoma maligno (MM), por ser aquellas patologías en las que se concentró la transferencia de competencias asistenciales. Evolución cronológica de las competencias asumidas por los diferentes perfiles durante su integración en el equipo de CRG. Resultados: La actividad asistencial de CRG durante el periodo analizado experimentó un incremento del 109%. CaM y MM son las patologías que aglutinaron con diferencia una mayor demanda asistencial. La transferencia de competencias en estas dos patologías se ha producido de manera progresiva, asumiendo en 2022 el 74% (460/622) de la fase de administración el ERGC y el 64% (333/519) de las cirugías el TSID. Conclusiones: La creación de un equipo multidisciplinar de CRG, que incluye distintos perfiles profesionales (MN, ERGC y TSID), es una eficaz estrategia para dar respuesta al incremento de la complejidad y número de todos los procedimientos relacionados con la CRG.(AU)

Introduction: Given the constant increase in the healthcare demand for examinations related to radio-guided surgery (RGS), our hospital adopted new professional profiles in the RGS team, in order to partially reduce the time spent by nuclear medicine physicians on this task. Aim: To analyze the process of incorporating the profiles of Superior Diagnostic Imaging Technician (TSID) and Sentinel Node Referent Nurse (ERGC), evaluating their deployment in the procedures linked to the technique. Material and methods: Analysis of RGS activity during the period 2018-2022, focusing on pre-surgical and surgical procedures related to breast cancer (BC) and malignant melanoma (MM), as they are those pathologies on which the transfer of care competencies was concentrated. Chronological evolution of the competencies assumed by the different profiles during their integration into the RGS team. Results: RGS's healthcare activity during the analyzed period experienced an increase of 109%. BC and MM were the pathologies that accounted for by far the greatest demand for care. The transfer of competencies in these two pathologies occurred in a progressive and staggered manner, with 74% (460/622) of the administration phase being carried out by the ERGC and 64% (333/519) of the surgeries by the TSID in 2022. Conclusions: The creation of a multidisciplinary RGS team that includes different professional profiles (NM, ERGC and TSID) is an effective strategy to respond to the increase in the complexity and number of all procedures related to RGS.(AU)

Correlación entre los índices estandarizados SUVmáx de la PET/TC con [68Ga]Ga-PSMA-I&T pre-prostatectomía radical y los resultados histopatológicos finales: un análisis en profundidad / Correlation between pre-radical prostatectomy Standardized SUVmax ratios detected on 68Ga-PSMA-I&T PET/CT and final histopathology outcomes: An in-depth analysis

Objetivo: Evaluar el potencial predictivo del valor máximo de captación estandarizada (SUVmáx) de los tumores intraprostáticos obtenidos en la PET/TC preoperatoria con [68Ga]Ga-PSMA-I&T (SUVT), así como sus relaciones con el SUVmáx en el hígado (SUVTLR) y la glándula parótida (SUVTPR) con respecto a los hallazgos histopatológicos. Material y métodos: Se evaluaron los datos de pacientes sometidos a prostatectomía radical (PR) por cáncer de próstata (CaP) en nuestra clínica entre los años 2017-2020. Se excluyeron aquellos pacientes con una neoplasia maligna secundaria, antecedentes de resección transuretral de próstata, tratamiento previo para CaP o que fueron sometidos a una PR de rescate. Dos especialistas en medicina nuclear con más de una década de experiencia cada uno revisaron las imágenes del estudio de cuerpo completo obtenidas con el mismo equipo, según protocolo, para obtener el consenso en cada lesión. Se estudiaron las relaciones entre edad, antígeno específico de la próstata (PSA), volumen de la próstata, estadio clínico, el grado de la clasificación de la Sociedad Internacional de Anatomía Patología Urológica (ISUP, por sus siglas en inglés) en la biopsia, el grupo de riesgo de D’amico, el volumen tumoral intraprostático identificado en la revisión histopatológica final de la muestra (HPTV) y el grado HP-ISUP. Se analizó la invasión de vesículas seminales (SVI), la invasión extracapsular (ECI), el margen quirúrgico positivo (PSM), SUVT, SUVTLR y SUVTPR. Resultados: La edad media de los 64 pacientes incluidos fue de 64,1±5,3 años. Se observó una correlación estadísticamente significativa entre los valores de SUVT, SUVTLR, SUVTPR y los parámetros del estadio histopatológico, como el grado ISUP de la biopsia, la clasificación de riesgo D’amico, HP-ISUP, HPTV (p<0,05). PSMATV, SUVT y SUVTLR fueron predictores estadísticamente significativos de invasión extracapsular, mientras que PSA, PSMATV y SUVTLR fueron predictores significativos de SVI (p<0,05)... (AU)

Objective: To evaluate the predictive potential of the maximum standardized uptake value (SUVmax) value of intraprostatic tumors derived from preoperative [68Ga]Ga-PSMA-I&T PET/CT (SUVT), and its ratios to SUVmax in the liver (SUVTLR) and parotid gland (SUVTPR) with respect to histopathological findings. Materials and methods: Data from patients who underwent radical prostatectomy (RP) for prostate cancer (PC) at our clinic between 2017-2020 were assessed. Patients with a secondary malignancy, a history of transurethral prostate resection, prior treatment for PC, or who received salvage RP were excluded. Whole-body images obtained using the same device, as per the guidelines, were reviewed by two nuclear medicine specialists with more than a decade of experience to reach a consensus for each lesion. The relationships between age, PSA, Prostate Volume, clinical T stage, biopsy International Society of Urological Pathology grade (ISUP), D’amico risk group, intraprostatic tumor volume (HPTV) identified in the final histopathological specimen review, HP-ISUP grade, seminal vesicle invasion (SVI), extracapsular invasion (ECI), positive surgical margine (PSM), SUVT, SUVTLR, and SUVTPR were analyzed. Results: The mean age of the 64 included patients was 64.1±5.3 y-o. A statistically significant correlation was found between SUVT, SUVTLR, SUVTPR values, and histopathologic stage parameters, such as biopsy ISUP, D’amico Risk Classification, HP-ISUP, HPTV (P<.05). PSMATV, SUVT, and SUVTLR were statistically significant predictors of extracapsular invasion, while PSA, PSMATV, and SUVTLR were significant predictors of SVI (P<.05). Conclusion: The standardized SUVT, SUVTLR, and SUVTPR values could be employed as noninvasive markers to assist in predicting postoperative histopathological findings, particularly ECI, SVI, and PSM. (AU)

Exploring Aqueous Coordination Chemistry of Highly Lewis Acidic Metals with Emerging Isotopes for Nuclear Medicine.

ConspectusNuclear medicine harnesses radioisotopes for the diagnosis and treatment of disease. While the isotopes 99mTc and 111In have enabled the clinical diagnosis of millions of patients over the past 3 decades, more recent clinical translation of numerous 68Ga/177Lu-based radiopharmaceuticals for diagnostic imaging and therapy underscores the clinical utility of metal-based radiopharmaceuticals in mainstream cancer treatment. In addition to such established radionuclides, advancements in radioisotope production have enabled the production of radionuclides with a broad range of half-lives and emission properties of interest for nuclear medicine. Chemical means to form kinetically inert, in vivo-compatible species that can be modified with disease-targeting vectors is imperative. This presents a challenge for radiosiotopes of elements where the aqueous chemistry is still underdeveloped and poorly understood. Here, we discuss our efforts to date in exploring the aqueous, radioactive coordination chemistry of highly Lewis acidic metal ions and how our discoveries apply to the diagnosis and treatment of cancer in preclinical models of disease. The scope of this Account includes approaches to aqueous coordination of to-date understudied highly Lewis acidic metal ions with radioisotopes of emerging interest and the modulation of well-understood coordination environments of radio-coordination complexes to induce metal-catalyzed reactivity for separation and pro-drug applications.First, we discuss the development of seven-coordinate, small-cavity macrocyclic chelator platform mpatcn/picaga as an exemplary case study, which forms robust complexes with 44Sc/47Sc isotopes. Due to the high chemical hardness and pronounced Lewis acidity of the Sc3+ ion, the displacement of ternary ligand H2O by 18/natF- can be achieved to form an inert Sc-18/natF bond. Corresponding coordination complex natSc-18F is in vivo compatible and forms a theranostic tetrad with corresponding 44Sc/47Sc, 177Lu complexes all exhibiting homologous biodistribution profiles. Another exceptionally hard, highly Lewis acidic ion with underdeveloped aqueous chemistry and emerging interest in nuclear medicine is 45Ti4+. To develop de novo approaches to the mononuclear chelation of this ion under aqueous conditions, we employed a fragment-based bidentate ligand screening approach which identified two leads. The screen successfully predicted the formation of [45Ti][Ti(TREN-CAM)], a Ti-triscatechol complex that exhibits remarkable in vivo stability. Furthermore, the fragment-based screen also identified approaches that enabled solid-phase separation of Ti4+ and Sc3+ of interest in streamlining the isotope production of 45Ti and accessing new ways to separate 44Ti/44Sc for the development of a long-lived generator system. In addition to establishing the inert chelation of Ti4+ and Sc3+, we introduce controlled, metal-induced reactivity of corresponding coordination complexes on macroscopic and radiotracer scales. Metal-mediated autolytic amide bond cleavage (MMAAC) enables the temperature-dependent release of high-molar-activity, ready-to-inject radiopharmaceuticals; cleavage is selectively triggered by coordinated trivalent Lewis acid nat/68Ga3+ or Sc3+. Following the scope of reactivity and mechanistic studies, we validated MMAAC for the synthesis of high-molar-activity radiopharmaceuticals to image molecular targets with low expression and metal-mediated prodrug hydrolysis in vivo.This Account summarizes how developing the aqueous coordination chemistry and tuning the chemical reactivity of metal ions with high Lewis acidity at the macroscopic and tracer scales directly apply to the radiopharmaceutical synthesis with clinical potential.

Occupational skin dose from radionuclide contamination: one country's approach at standardising skin dose estimates using Varskin.

The manipulation of unsealed radiopharmaceuticals by healthcare workers can cause accidental personal contamination leading to occupational radiation skin dose. The UK Ionising Radiations Regulations 2017 require that potential skin doses arising from reasonably foreseeable accident scenarios are included in risk assessments. Workers must be designated as classified if these dose estimates exceed 150 mSv equivalent dose averaged over 1 cm2. Updates from the UK Health and Safety Executive recently prompted many in the UK to review the classification of workers in Nuclear Medicine. Skin dose from contamination cannot be measured, it must be estimated. Varskin+ is a code that is widely recommended for estimating skin dose. The subjective choices made by users when defining modelled scenarios in Varskin+ lead to significant variation in the calculated skin doses. At the time of writing there is no definitive calculation method and all calculations rely on theoretical models. NHS Health Boards in Scotland have adopted a standardised framework for performing skin dose estimates for risk assessments. The parametric sensitivity of Varskin+ inputs were examined and the available evidence was reviewed. Generic, reasonably forseeable, worst-case accident scenarios were decided upon for: direct skin contamination, glove contamination and needlestick injury. Standardised inputs and assumptions for each scenario were compiled in a protocol that has been adopted by the Scottish Health Boards. The protocol allows for differences in practice between departments, but standardises most inputs. While significant uncertainty remains in the estimated skin doses, this approach reduces variation and enables the comparison of estimated skin doses between departments. The framework facilitates continuous improvement as more evidence is gathered to refine the standardised assumptions. Task by task skin dose estimates were made for workers in Nuclear Medicine in Scotland and many workers were designated classified as a result.

Research progress on asialoglycoprotein receptor-targeted radiotracers designed for hepatic nuclear medicine imaging.

Asialoglycoprotein receptor (ASGPR) specifically recognizes glycans terminated with ß-d-galactose or N-acetylgalactosamine. Its exclusive expression in mammalian hepatocytes renders it an ideal hepatic-targeted biomarker. To date, ASGPR-targeted ligands have been actively developed for drug delivery and hepatic imaging. This review provides a comprehensive summary of the progress achieved to-date in the field of developing ASGPR-targeted nuclear medicine imaging (NMI) radiotracers, highlighting the recent advancements over the last decade in terms of structure, radionuclides and labeling strategies. The biodistribution patterns, imaging characteristics, challenges and future prospective are discussed.

Knowledge and practices of radiation protection among Malaysian radiographers working in nuclear medicine: A preliminary study.

This study is aimed to determine knowledge and practices on radiation protection among radiographers in nuclear medicine department. A cross-sectional survey was conducted among radiographers in nuclear medicine departments in four health institutions in Malaysia. A set of questionnaires was distributed to 17 respondents using convenience sampling. Approximately more than 75% and 44% - 56% of the radiographers have good knowledge of radiation protection and frequent adherence to radiation protection practices, respectively. Levels of education and length of service were statistically correlated with radiation protection knowledge and practices attributes (p < 0.05), respectively. More training is necessary for knowledge and practice improvement.

Nuclear medicine and pediatric nephro-urology: a long-lasting successful partnership.

Congenital anomalies of the kidney and urinary tract, as well as urinary infections, are very frequent in children. After the clinical and laboratory evaluation, the first imaging procedure to be done is a renal and bladder ultrasound, but afterwards, a main contribution comes from nuclear medicine. Through minimally invasive and sedation-free procedures, nuclear medicine allows the evaluation of the functional anatomy of the urinary tract, and the quantification of renal function and drainage. If pediatric dosage cards provided by scientific societies are used, radiation exposure can also be low. In the pediatric conditions previously mentioned, nuclear medicine is used both for initial diagnosis and follow-up, mostly in cases of suspicion of ureteropelvic or ureterovesical junction syndromes, as well as vesicoureteral reflux or renal scars of febrile infectious episodes. Pediatric nephro-urology constitutes a significant workload of pediatric nuclear medicine departments. The following paragraphs are a revision of the renal radiopharmaceuticals, as well as the nuclear nephro-urology procedures - dynamic and static renal scintigraphy, and direct and indirect radionuclide cystography. A summary of the techniques, main indications, interpretation criteria and pitfalls will be provided. Some future directions for the field are also pointed out, among which the most relevant is the need for nuclear medicine professionals to use standardized protocols and integrate multidisciplinary teams with other pediatric and adult health professionals that manage these life-long pediatric pathologies, which are recognized as an important cause of adult chronic kidney disease.

Fever of unknown origin in pediatrics: role of nuclear medicine.

Fever of unknown origin (FUO) is a debated issue in numerous scientific studies in adult patients with a not jet-defined workflow in a clinical and diagnostic setting. Few works are published about pediatric patients even if FUO represents a challenging, not infrequent scenario in hospital and outpatient recovery. The fever might be the onset symptom of a transient mild infection or the beginning of a more difficult-to-diagnose and serious pathological condition. In the adult workflow 18FDG PET-CT is nowadays playing a relevant role, considering the limited spread of conventional 99mTc-HMPAO-White Blood Cells scintigraphy. It represents a robust tool for diagnosing the eventual site of infection, but it is limited by procedural complexity and long duration, up to 24 hours. The WBC-scintigraphy is also not suitable for children, only for young adults or adolescents, considering the relevant blood sample entity and the procedural risk for sensitive subjects. The most assessed clinical and diagnostic know-how on Pediatric FUO are summarized and a synthetic flow-chard is presented to support the clinical management and to choose the best diagnostic pathway.

Gastric Emptying Studies in Pediatrics: A Cincinnati Children's Hospital Experience.

Gastric emptying studies are routinely performed in many nuclear medicine departments; however, there are many different techniques used to perform the procedure across the country. Creating consistency in clinical practice will aid gastroenterologists in diagnosing and treating illnesses associated with abnormalities related to gastric emptying. In 2017, Cincinnati Children's Hospital adopted adult standards for pediatric gastric emptying studies that included a standard meal along with imaging over the course of 4 h. Gastric emptying studies are the second-highest-volume examination performed in the nuclear medicine section at Cincinnati Children's Hospital. Accommodating this volume required changes in the scheduling template, scheduling questionnaire, and epic order sets, as well as identification of specific days and locations for gastric emptying studies. Both protocol standardization and workflow optimization are critically important in creating consistency in patient care. Gastric emptying can be evaluated with solid food, liquid food, or solid and liquid food simultaneously. The methodology of the study is initially determined by the ordering provider but may require special accommodations based on what the patient will tolerate. In coordination with the ordering and interpreting physicians, the nuclear medicine technologists at Cincinnati Children's Hospital have the decision-making ability to deviate from the provider's request as necessary, which helps expedite workflow and eliminates wasted time. Any deviation from the standardized protocol is documented by the nuclear medicine technologist and incorporated into the final report by the interpreting physician, as dietary information is meaningful to the ordering provider. Reference values associated with the standardized or modified protocol are also included in the final report.

An Evaluation of Gastric Emptying Scintigraphy Protocols in Health Care Institutions When Compared with the Society of Nuclear Medicine and Molecular Imaging Procedure Guidelines.

This study aimed to analyze the compliance of health care institutions with the Society of Nuclear Medicine and Molecular Imaging (SNMMI) procedure guidelines for gastric emptying scintigraphy (GES). Methods: A 19-question survey on demographics and the GES protocol was conducted using a Google form. The demographic questions covered position, number of technologists in the department, location, type of health care institution, and number of GES studies per month. The protocol questions included patient preparation, meal preparation, withholding of scheduled medications, radiopharmaceutical type, and radiopharmaceutical dose. The survey was sent to 7 nuclear medicine Facebook groups and a list of clinical affiliates provided by the Indiana University School of Medicine Nuclear Medicine Program. Descriptive statistics were compiled for most questions. A Fisher exact test with a significance level of 0.05 was used to compare the type of health care institution with compliance with the SNMMI GES protocol regarding radiolabeling time, meal preparation, and meal components, as well as to compare the type of health care institution with the number of GES studies performed per institution. Results: In total, 240 people responded to the survey. Most were nonsupervisory nuclear medicine technologists (72%) in nonacademic institutions (72%) and groups with 4 or more technologists (62%). Of the respondents, 72% followed the SNMMI guideline of adding the radiopharmaceutical before cooking, but only 37% followed the meal component guideline. There was no significant association between the type of institution or the number of GES studies and compliance with radiolabeling time or with meal preparation or components. Most respondents asked patients to withhold medications per SNMMI guidelines and used the recommended radiopharmaceutical (99mTc-sulfur colloid, 95%) at the recommended dose (18.5-37 MBq, 84%). Conclusion: Although most respondents followed most aspects of the SNMMI guidelines for GES, more than half did not use the recommended meal of liquid egg whites. Compliance did not vary between academic and nonacademic institutions or between groups performing a large or a small number of GES studies.

Tata Memorial Centre Evidence Based Use of Nuclear medicine diagnostic and treatment modalities in cancer.

ABSTRACT: PET/CT and radioisotope therapy are diagnostic and therapeutic arms of Nuclear Medicine, respectively. With the emergence of better technology, PET/CT has become an accessible modality. Diagnostic tracers exploring disease-specific targets has led the clinicians to look beyond FDG PET. Moreover, with the emergence of theranostic pairs of radiopharmaceuticals, radioisotope therapy is gradually making it's way into treatment algorithm of common cancers in India. We therefore would like to discuss in detail the updates in PET/CT imaging and radionuclide therapy and generate a consensus-driven evidence based document which would guide the practitioners of Oncology.

EANM guidance document: dosimetry for first-in-human studies and early phase clinical trials.

The numbers of diagnostic and therapeutic nuclear medicine agents under investigation are rapidly increasing. Both novel emitters and novel carrier molecules require careful selection of measurement procedures. This document provides guidance relevant to dosimetry for first-in human and early phase clinical trials of such novel agents. The guideline includes a short introduction to different emitters and carrier molecules, followed by recommendations on the methods for activity measurement, pharmacokinetic analyses, as well as absorbed dose calculations and uncertainty analyses. The optimal use of preclinical information and studies involving diagnostic analogues is discussed. Good practice reporting is emphasised, and relevant dosimetry parameters and method descriptions to be included are listed. Three examples of first-in-human dosimetry studies, both for diagnostic tracers and radionuclide therapies, are given.

Terbium radionuclides for theranostic applications in nuclear medicine: from atom to bedside.

Terbium features four clinically interesting radionuclides for application in nuclear medicine: terbium-149, terbium-152, terbium-155, and terbium-161. Their identical chemical properties enable the synthesis of radiopharmaceuticals with the same pharmacokinetic character, while their distinctive decay characteristics make them valuable for both imaging and therapeutic applications. In particular, terbium-152 and terbium-155 are useful candidates for positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging, respectively; whereas terbium-149 and terbium-161 find application in α- and ß--/Auger electron therapy, respectively. This unique characteristic makes the terbium family ideal for the "matched-pair" principle of theranostics. In this review, the advantages and challenges of terbium-based radiopharmaceuticals are discussed, covering the entire chain from radionuclide production to bedside administration. It elaborates on the fundamental properties of terbium, the production routes of the four interesting radionuclides and gives an overview of the available bifunctional chelators. Finally, we discuss the preclinical and clinical studies as well as the prospects of this promising development in nuclear medicine.

Advancements in the development of radiopharmaceuticals for nuclear medicine applications in the treatment of bone metastases.

Bone metastases are a painful and complex condition that overwhelmingly impacts the prognosis and quality of life of cancer patients. Over the years, nuclear medicine has made remarkable progress in the diagnosis and management of bone metastases. This review aims to provide a comprehensive overview of the recent advancements in nuclear medicine for the diagnosis and management of bone metastases. Furthermore, the review explores the role of targeted radiopharmaceuticals in nuclear medicine for bone metastases, focusing on radiolabeled molecules that are designed to selectively target biomarkers associated with bone metastases, including osteocytes, osteoblasts, and metastatic cells. The applications of radionuclide-based therapies, such as strontium-89 (Sr-89) and radium-223 (Ra-223), are also discussed. This review also highlights the potential of theranostic approaches for bone metastases, enabling personalized treatment strategies based on individual patient characteristics. Importantly, the clinical applications and outcomes of nuclear medicine in osseous metastatic disease are discussed. This includes the assessment of treatment response, predictive and prognostic value of imaging biomarkers, and the impact of nuclear medicine on patient management and outcomes. The review identifies current challenges and future perspectives on the role of nuclear medicine in treating bone metastases. It addresses limitations in imaging resolution, radiotracer availability, radiation safety, and the need for standardized protocols. The review concludes by emphasizing the need for further research and advancements in imaging technology, radiopharmaceutical development, and integration of nuclear medicine with other treatment modalities. In summary, advancements in nuclear medicine have significantly improved the diagnosis and management of osseous metastatic disease and future developements in the integration of innovative imaging modalities, targeted radiopharmaceuticals, radionuclide production, theranostic approaches, and advanced image analysis techniques hold great promise in improving patient outcomes and enhancing personalized care for individuals with bone metastases.