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Purpose The aim of this retrospective multicentric study was to investigate the diagnostic performance, the prognostic value and the impact of 18F-FDG PET/CT on treatment decision-making in patients with suspected recurrent vulvar cancer (VC). Materials and methods Sixty-three patients affected by VC performed 18F-FDG-PET/CT for restaging purposes in case of suspected clinical and/or radiological recurrence. Histopatology results if available and/or clinical-imaging follow-up for at least 12 months were considered as reference standard. The diagnostic accuracy and the clinical impact of 18F-FDG PET/CT were investigated. Progression free survival (PFS) and overall survival (OS) were calculated using Kaplan–Meier curves. Results Fifty-two (82.5%) PET/CT showed the presence of recurrence, while the remaining 11 (17.5%) were negative. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT were 100% (95%CI 93–100%), 92% (95%CI 62–100%), 98% (95%CI 89–99%), 100% and 98% (95%CI 92–100%). A relevant impact of 18F-FDG PET/CT imaging was registered in 28 cases: in 12 cases moving from local therapy to chemotherapy due to the recognition of disseminate localizations; in 10 showing the site of recurrence in presence of negative conventional imaging, and in 6 cases confirming to be true negative and avoiding unnecessary therapies. Beside advanced age and HPV status, a positive restaging 18F-FDG PET/CT scan was significantly correlated with shorter PFS and OS compared to negative scan (p Conclusions 18F-FDG PET/CT demonstrated to be an accurate tool in the assessing of recurrent VC with high sensitivity and specificity and with a significant impact on clinical decision-making. Restaging 18F-FDG PET/CT findings were associated with survival.

PET/CT is the standard for quantitative assessments of myocardial blood flow (MBF), but it requires short-lived-tracers, costly, and not widely available. SPECT with Cadmium Zinc Telluride (CZT) detectors allows dynamic acquisition and quantitation of MBF. The study aims were to compare MBF measurements by 99mTc-tetrofosmin-CZT to N13NH3 PET/CT after regadenoson-induced coronary hyperemia and to evaluate the effect of attenuation correction (AC). 54 patients were evaluated at rest and during vasodilation by 99mTc-tetrofosmin-CZT and N13NH3 PET/CT within 2 weeks. MBF and MBF reserve (MFR) were measured by CZT with or without AC (NAC). The global rest MBF was 0.76 ± 0.19 mL/min/gr by PET and 0.76 ± 0.24 by AC-CZT (P = NS) and 1.14 ± 0.4 by NAC-CZT (P < 0.001 vs PET and AC-CZT). Stress MBF was higher when measured by PET than AC-CZT (1.87 ± 0.45 vs 1.62 ± 0.68 mL/min/gr, P < 0.0008), but lower than NAC-CZT (2.36 ± 1.1, P < 0.0003). The MBF reserve ratio (MFR) was higher by PET than AC-CZT (2.52 ± 0.56 vs 2.22 ± 1 (P < 0.009) and NAC-CZT (2.18 ± 1.0, P < 0.004). Linear regression was better between PET (MFR and stress MBF) and AC-CZT than between PET and NAC-CZT. ROC curve analysis showed the significant ability of AC-CZT to predict MFR < 2 and stress MBF < 1.7 (AUC = 0.75 and 0.82 respectively) and to differentiate between normal and CAD patients (AUC = 0.747 and 0.892 for MFR and stress MBF, respectively). Our data show a reasonable correlation between MBF and MFR measured by N13NH3-PET and 99mTc-Tetrofosmin-CZT SPECT. NAC-CZT overestimates MBF. AC is recommended when using CZT for measuring MBF.

espanolObjetivo Analizar las caracteristicas epidemiologicas y antropometricas de los pacientes con activacion de la grasa parda detectada por tomografia por emision de positrones con fluoruro 18-fluorodeoxiglucosa/tomografia computarizada (18F-FDG PET/TC). Material y metodos De 2005 a 2017, se incluyeron retrospectivamente 818 estudios PET/TC con 18F-FDG positivos para deteccion de grasa parda, 742 examenes realizados en poblacion adulta y 76 PET/TC en poblacion pediatrica. Se realizo una prueba de Chi cuadrado para comparar la distribucion de las caracteristicas entre pacientes adultos y pediatricos. Resultados Los adultos mostraron una tasa mas alta de deteccion de grasa parda en mujeres (79% vs. 61%, p 100 mg/dl) (24% vs. 16%, p = 0,02), no se encontraron diferencias significativas considerando el sobrepeso (IMC > 25 kg/m2) (22% vs. 20%, p = 0,55). Teniendo en cuenta solo a mujeres, los adultos mostraron una tasa mas alta de deteccion de grasa parda tanto en pacientes con hiperglucemia (83% frente a 42%, p Conclusiones El sexo, la glucemia y el IMC desempenan un papel importante en la prediccion de la activacion de la grasa parda, con diferencias significativas entre adultos y ninos. Se confirma que la exposicion al frio es un factor de prediccion importante, mientras que la temporada de nacimiento no es significativa. EnglishPurpose To analyze epidemiological and anthropometric features of patients with brown adipose tissue (BAT) activation detected by fluorine18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Material and methods From 2005 to 2017, 818 18F-FDG PET/CT studies positive for BAT detection were retrospectively included, 742 examinations performed on the adult population and 76 PET/CT on the pediatric population. A Chi-squared test was performed to compare features distribution between the adult and pediatric patients. Results Adults showed a higher rate of BAT detection in females (79% vs. 61%, P100 mg/dL) (24% vs. 16%, P=0.02), no significant difference was found with regard to overweight patients (BMI > 25 kg/m2) (22% vs. 20%, P=.55). Considering females only, the adults showed a higher rate of BAT detection both in hyperglycaemic (83% vs. 42%, P Conclusions Sex, glycemia and BMI play a major role in predicting BAT activation, with significant differences between adults and pediatric patients. Cold exposure is confirmed as an important predicting factor, while season of birth is not significant.

Purpose To analyze epidemiological and anthropometric features of patients with brown adipose tissue (BAT) activation detected by fluorine18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Materials and methods From 2005 to 2017, 818 18F-FDG PET/CT studies positive for BAT detection were retrospectively included, 742 examinations performed on the adult population and 76 PET/CT on the pediatric population. A Chi-squared test was performed to compare features distribution between the adult and pediatric patients. Results Adults showed a higher rate of BAT detection in females (79% vs 61%, p 100 mg/dL) (24% vs 16%, p=0.02), no significant difference was found with regard to overweight patients (BMI > 25 kg/m2) (22% vs 20%, p=0.55). Considering females only, the adults showed a higher rate of BAT detection both in hyperglycaemic (83% vs 42%, p Conclusions Sex, glycemia and BMI play a major role in predicting BAT activation, with significant differences between adults and pediatric patients. Cold exposure is confirmed as an important predicting factor, while season of birth is not significant.

Thyroid incidentaloma is defined as a thyroid lesion incidentally and newly detected by imaging techniques performed for an unrelated purpose and especially for a non-thyroid disease. The aim of this review is to evaluate the prevalence and clinical significance of focal incidental radiolabelled prostate-specific membrane antigen (PSMA) uptake in the thyroid gland [PSMA thyroid incidentaloma (PTI)] revealed by PET/CT or PET/MRI. A comprehensive literature search of the PubMed/MEDLINE, Scopus, and Embase databases was conducted to find relevant published articles about the prevalence and clinical significance of PTIs detected by PET/CT or PET/MRI in patients studied for other oncologic purposes. Twelve articles were included in the systematic review. Among 23 PTIs, 6 were malignant (5 primary thyroid tumors and one metastasis from renal cell carcinoma), one was a follicular lesion of undetermined significance, and the rest were benign. Despite being very rare, though probably underestimated, PTIs frequently signal the presence of unexpected lesions in the thyroid which differ from the indicated reason for which the patient was initially scanned and concerning which the risk of malignancy is not negligible.

Pericardial synovial sarcoma is a rare malignancy. We report the case of a patient who was referred to our institution for a large pericardial effusion requiring pericardiocentesis. CT imaging revealed an inhomogeneous pericardial mass beside the right atrium, and then a PET/CT scan was performed. Standard images were inconclusive whether delayed images showed an FDG-avid pericardial lesion that was surgically removed with histological diagnosis of a poorly differentiated biphasic synovial sarcoma. When considering mediastinal or pericardial mass, a delayed PET/CT may improve lesion-to-background contrast by reducing blood pool activity.

Prostate cancer with extensive dural metastases is very rare, with only few cases described in the literature. We report one such case of a 74-year-old man with advanced prostate cancer, and in relatively good clinical condition. The patient returned with complaints of headache and diplopia. Fluorocholine (18F) chloride (18F-FCH) is an analog of choline in which a hydrogen atom has been replaced by fluorine (18F). After crossing the cell membrane by a carrier-mediated mechanism, choline is phosphorylated by choline kinase to produce phosphorylcholine. 18F-FCH positron emission tomography–computed tomography (PET/CT) is widely used to stage and restage patients affected by prostate cancer with good sensitivity. 18F-FCH PET/CT showed disease progression with the onset of multiple skull lesions. Numerous suspicious dural hypermetabolic lesions indicating neoplastic involvement were detected along the fronto-parietal convexities, in the left fronto-orbital region and right lateral wall of the orbit, concerning for metastases in these regions. A contrast-enhanced computed tomography (CECT) scan was performed which showed corresponding enhancing tissue which correlated with the PET findings. The final imaging diagnosis was osteo-dural metastases from prostate cancer associated with poor outcome. Awareness of this pattern of metastases may be of clinical relevance in order to avoid unnecessary invasive diagnostic procedures in groups of patients with a dismal prognosis.

Resumen Objetivo Despues de la inyeccion del radiofarmaco se observa con frecuencia una concentracion incrementada de 123I-MIBG en el lobulo hepatico izquierdo en comparacion con el derecho, pero la razon de este hallazgo sigue siendo desconocida. Nuestro objetivo fue analizar retrospectivamente el patron de absorcion de 123I-MIBG entre los 2 lobulos hepaticos y correlacionar nuestros resultados con algunas caracteristicas epidemiologicas/clinicas. Material y metodos Se seleccionaron 94 gammagrafias 123I-MIBG de 71 pacientes. Las regiones de interes se dibujaron en los lobulos derecho e izquierdo utilizando secciones tomograficas transversales y se calcularon relaciones de actividad de izquierda a derecha (relacion I/D) a las 6 y 24 horas de la administracion del radiofarmaco. Resultados Veintisiete examenes fueron positivos para lesiones hipermetabolicas, mientras que los 67 restantes fueron negativos. En todos los casos las relaciones medias de I/D temprana y tardia fueron superiores a 1; la relacion I/D temprana media fue de 1,37 y la relacion I/D tardia de 1,52. La relacion I/D tardia fue significativamente mayor que la precoz. No hubo diferencias en la relacion I/D con respecto a la edad, sexo, enfermedad primaria y resultado de la gammagrafia. Conclusiones La absorcion de 123I-MIBG fue mayor en el lobulo hepatico izquierdo en comparacion con el derecho, y esta relacion no se correlaciono con ninguna caracteristica epidemiologica o clinica. La razon de este metabolismo todavia no se ha explicado, y algunas hipotesis biomoleculares podrian ser probadas en modelos 3D dinamicos in vitro.

Background Myocardial perfusion imaging is a well-established diagnostic tool in patients with known or suspected coronary artery disease. Numerous clinical trials have shown that attenuation correction (AC) in single photon emission computed tomography (SPECT) improves the diagnostic accuracy of myocardial perfusion imaging over non-AC SPECT, differentiating between scar and attenuation artifacts. We have previously shown that attenuation artifacts produce an overestimation of the size of inferior infarcts in the male population. It is assumed that women are less affected by inferior attenuation artifacts than men. Purpose The aim of this study is to evaluate the role of AC in the assessment of infarct size in female patients with a history of myocardial inferior infarct. Patients and methods We studied a population of 66 consecutive women, with a history of previous inferior myocardial infarct, by SPECT/computed tomography (CT) with 370+370 MBq of technetium-99m labeled compounds by a 2-day stress-rest protocol. Both AC and uncorrected gated-SPECT/CT studies were reconstructed after scatter and motion correction by ordered-subset expectation maximization iterative reconstruction and resolution recovery. The coregistration of the transmission and emission scans was verified for all patients; any misalignment was realigned manually. Uncorrected and corrected SPECT images were analyzed by software QPS/QGS package using a 17-segment model. For each segment, perfusion and wall motion were quantified using a five-point score according to the American Society of Nuclear Cardiology guidelines. Summed stress, summed rest score (SRS), and summed difference score of the inferior left ventricle wall (inferior, inferoseptal, inferolateral, and apical inferior segments) were calculated. A linear correlation was used to assess the relationship between perfusion and the regional wall motion score as determined by uncorrected gated-SPECT. Results The results of quantitative analysis of non-AC and CT-AC SPECT images, respectively, were as follows: summed stress score: 9.47±5.01 and 6.58±4.77% (P

F-Fluorocholine (F-FCH) PET/CT is widely used to study patients affected by prostate cancer. F-FCH PET/CT is suitable for the detection of pelvic and abdominal nodal and skeletal metastases. Indeed, F-FCH PET/CT sensitivity for other organs, such as the liver and the urinary tract, is lowered by the radiopharmaceutical urinary washout and intense liver uptake. Herein, we report the case of a patient affected by oligometastatic prostate cancer in good clinical condition treated with total androgen blockade. F-FCH PET/CT showed a diffuse and intense uptake in the shaft of the penis, which was an evidence of a rare penile metastasis.

PET/CT is the standard for quantitative assessments of myocardial blood flow (MBF), but it requires short-lived-tracers, costly, and not widely available. SPECT with Cadmium Zinc Telluride (CZT) detectors allows dynamic acquisition and quantitation of MBF. The study aims were to compare MBF measurements by54 patients were evaluated at rest and during vasodilation byThe global rest MBF was 0.76 ± 0.19 mL/min/gr by PET and 0.76 ± 0.24 by AC-CZT (P = NS) and 1.14 ± 0.4 by NAC-CZT (P0.001 vs PET and AC-CZT). Stress MBF was higher when measured by PET than AC-CZT (1.87 ± 0.45 vs 1.62 ± 0.68 mL/min/gr, P0.0008), but lower than NAC-CZT (2.36 ± 1.1, P0.0003). The MBF reserve ratio (MFR) was higher by PET than AC-CZT (2.52 ± 0.56 vs 2.22 ± 1 (P0.009) and NAC-CZT (2.18 ± 1.0, P0.004). Linear regression was better between PET (MFR and stress MBF) and AC-CZT than between PET and NAC-CZT. ROC curve analysis showed the significant ability of AC-CZT to predict MFR2 and stress MBF1.7 (AUC = 0.75 and 0.82 respectively) and to differentiate between normal and CAD patients (AUC = 0.747 and 0.892 for MFR and stress MBF, respectively).Our data show a reasonable correlation between MBF and MFR measured by N

The aim of our study was to compare the efficacy of thyroid remnant ablation using low (1.1 GBq) and intermediate-high radioiodine (RAI) activity (1.85–3.7 GBq) in low-risk differentiated thyroid carcinoma (DTC) and to evaluate the staging role of the whole body scan (WBS) in detection extrathyroidal disease. We retrospectively included 277 patients who underwent total thyroidectomy and RAI for low-risk DTC and divided them in two groups according to RAI activity at ablation: group 1 (n = 174) treated with low activity (1.1 GBq), and group 2 (n = 103) with intermediate-high activity (1.85–3.7 GBq). To evaluate the successful ablation rate, the WBS 1 year after RAI was visually interpreted using a three-point scale: score 0 in case of absence of visible RAI uptake in thyroid bed; score 1 in presence of faint uptake in the thyroid bed; and score 2 in case of significant RAI uptake in thyroid bed. The success ablation rate was significantly higher in group 2 than group 1 (p

ObjectiveAccording to the 2015 American Thyroid Association (ATA) guidelines, thyroid ablation by iodine-131 (I-131) therapy is absolutely recommended only in patients with high-risk differentiated thyroid cancer (DTC). Often distant metastases are not recognized early and they can stay silent for long time. The aim of our study was to retrospectively analyze the prevalence of metastatic disease before and after I-131 and to evaluate the influence of the new ATA guidelines in the management of DTC.MethodsWe retrospectively analyzed 140 patients showing distant metastases. All metastases were detected by whole-body scan after I-131 and confirmed by histology and/or other imaging modalities.ResultsIn 26/140 patients metastases were detected before I-131, while in 114/140 were discovered after I-131. Comparing patients with metastases detected before and after I-131, no differences were demonstrated considering age, sex, histotype, tumor size, multifocality of cancer and metastatic localization. Metastatic DTC discovered before radioiodine had higher thyroglobulin and received a higher radioiodine total activity and number of treatments. Considering patients with distant metastases, according to the 2015 ATA guidelines, 38 patients would have been categorized as high risk, 22 as low risk and 80 as intermediate risk. Among intermediate-risk patients, only in 25 cases (31%) I-131 treatment would have been appropriate according to 2015 ATA recommendations; in the remaining 56 cases (69%), I-131 would not have been recommended.ConclusionsAccording to the 2015 ATA guidelines, most of metastatic patients would not have been treated after surgery, with the risk of late diagnosis and delayed treatment.

Purpose After radiopharmaceutical injection, a heightened 123I-MIBG concentration is frequently observed in the left hepatic lobe compared to the right one, but the reason of this finding remains unknown. Our aim was to retrospectively analyze the different 123I-MIBG uptake pattern between the two hepatic lobes and correlate our results with some epidemiological/clinical features. Methods Ninety-four 123I-MIBG scintigraphies from 71 patients were selected. Regions of interest were drawn in the right and left lobes using transverse tomographic sections and left to right activity ratios (L/R ratio) were calculated at 6 and 24 h after radiotracer administration. Results Twenty-seven examinations were positive for hypermetabolic lesions while the remaining 67 were negative. In all cases mean early and delayed L/R ratios were greater than 1.00; average early L/R ratio was 1.37 and delayed L/R ratio 1.52. The delayed L/R ratio was significantly higher than the early one. There was no difference in the L/R ratios with regard to age, gender, primary disease and result of scintigraphy. Conclusions 123I-MIBG uptake was higher in left hepatic lobe compared to right and this ratio did not correlate with any epidemiological or clinical feature. The reason of this metabolic is not yet explained and some biomolecular hypotheses could be tested in 3D dynamic in vitro models.

Both the myocardial perfusion pattern and myocardial blood flow (MBF) are used to assess patients with suspected coronary artery disease (CAD). The aim of this study was to compare the perfusion pattern (using the summed difference score [SDS]) to MBF in a consecutive group of patients undergoing PET/CT with 13 N-ammonia (13NH3). 47 consecutive patients, aged 65 ± 12 years (42 men) with known or suspected CAD, underwent vasodilator stress/rest PET/CT with 13NH3 for clinical indications. The SDS was determined by a commercially available software based on a 17-segment model. MBF was measured at rest and during hyperemia by dynamic acquisition and single-compartment model analysis. From the rest and stress MBF, the absolute difference (stress-rest) in myocardial blood flow defined as difference in myocardial blood flow (DMBF) was derived. There were no significant differences between patients with no ischemia (SDS ≤ 1) and those with ischemia (SDS > 1) in CFR (2.84 ± 0.73 vs 2.63 ± 0.89, P = NS) and DMBF (1.34 ± 0.45 vs 1.24 ± 0.53 mL·minute−1·g−1, P = NS). There were however significant regional differences (141 different vascular territories in 47 patients) between these two groups (CFR: 2.84 ± 0.95 vs 2.16 ± 0.57, P

Both the myocardial perfusion pattern and myocardial blood flow (MBF) are used to assess patients with suspected coronary artery disease (CAD). The aim of this study was to compare the perfusion pattern (using the summed difference score [SDS]) to MBF in a consecutive group of patients undergoing PET/CT with 13 N-ammonia (47 consecutive patients, aged 65 ± 12 years (42 men) with known or suspected CAD, underwent vasodilator stress/rest PET/CT withThere were no significant differences between patients with no ischemia (SDS ≤ 1) and those with ischemia (SDS 1) in CFR (2.84 ± 0.73 vs 2.63 ± 0.89, P = NS) and DMBF (1.34 ± 0.45 vs 1.24 ± 0.53 mL·minute