RESUMEN
BACKGROUND: The aim of this study was to verify the feasibility, in clinical practice, of three simplified methods (Hunter, Sadato and another one proposed by our group) to calculate Ki and MRglu of 18F-FDG, comparing the results with those derived by the linear regression (LR) method (considered the golden standard), and also with SUV. METHODS: Forty-five patients (32males, mean age 69±9years) with non-small-cell-lung cancer prospectively enrolled, underwent dynamic 18F-FDG PET-CT over the thorax. Ki was estimated as follows: from a static acquisition and performing one venous blood sampling using the Hunter method; multiplying the SUV for the average plasma clearance rate (kP(T)) and for the initial distribution volume (V0bw) without performing any blood sampling using the Sadato method; multiplying the SUV for a factor F (which encompasses the mean value of haematocrit and plasma volume, both according to patient's sex) without performing any blood sample using ours method. Wilcoxon signed rank and coefficient of determination (R2) were used for statistical analysis. RESULTS: No significant difference was observed between the Ki and MRglu estimated by all three simplified methods and the Ki and MRglu estimated by LR. The highest P values and the lower values of mean differences were observed with our method compared with LR: Ki=0.0392±0.0178 min-1 vs. Ki=0.0392±0.0202 min-1 (P=0.897, MD=0.0001 min-1), respectively; MRglu= 4.47±2.23 ml/min/100g vs. MRglu= 4.43±2.38 ml/min/100g (P=0.839, MD= -0.0373 mL/min/100g), respectively. The highest correlation was observed between the Ki estimated by both Hunter and our methods and the Ki estimated by LR: R2=0.87, R2=0.86, respectively. A good correlation (R2=0.83) was observed between SUV and Ki estimated by LR. CONCLUSIONS: These three simplified methods represent a valid alternative to the more invasive and complex full kinetic analysis. Their "pros" are: the non-invasiveness, the feasibility, the good correlation with the golden standard; their "cons" is that full kinetic analysis provides highest accuracy in Ki determination. Therefore, in clinical oncology routine, the nuclear physicians can choose among different simplified methods especially for monitoring the response to treatment, for tumour grading, and for prognostic stratification, letting the full kinetic analysis to specific centre/studies.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiofármacos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: In the framework of the British Antarctic Survey (BAS) Expedion JR 15005 SO-AntEco, held in February-March 2016, the South Orkney Islands seafloor was sampled in order to investigate the distribution and composition of benthic communities around the area. NEW INFORMATION: A new species of the genus Pseudidothea Ohlin, 1901 is described from the Burdwood Bank area (South Orkney Islands). It has been collected during the SO-AntEco JR15005 RRS James Clark Ross expedition under the lead of the British Antarctic Survey (BAS). The new species, Pseudidotheaarmata sp. n., is very similar to P.scutata (Stephensen, 1947); however, it is characterised by peculiar supra-ocular spines and a different tubercular pattern. The study of the species of the Pseudidothea helps to better understand the diversity of the Pseudidotheidae in the Southern Ocean.
RESUMEN
Peracarid data were collected in the Southern Ocean and South Atlantic Ocean. Sampling was performed during nine different expeditions on board of RRS James Clark Ross and RV Polarstern, using epibenthic sledges (EBS) at depth ranging between 160-6348 m at 109 locations. The correlation between environmental variables and peracarid abundance was investigated. Abundance data comprise a total of 128570 peracarids (52366 were amphipods, 28516 were cumaceans, 36142 isopods, 5676 mysidaceans and 5870 were tanaidaceans). The presented data are useful to investigate the composition and abundance patterns of peracarid orders at a wide depth range and spatial scale in the Southern Ocean. They can also be reused to compare their abundance with that of other taxa in broader ecological surveys.
RESUMEN
We report a case of an ectopic/hypoplastic kidney removed by radio-guided surgery. A 7-year-old girl, with a history of vaginal drainage of urine, underwent renal scintigraphy with Tc-DMSA. SPECT/CT revealed a focal uptake in the pelvis, corresponding to hypoplastic kidney as confirmed by MRI. Based on SPECT/CT findings, the patient underwent laparoscopic surgery, using Tc-DMSA scan to help the surgeon to detect the small ectopic kidney. Intraoperatory histological report confirmed the renal origin of the specimen.
Asunto(s)
Enfermedades Renales/cirugía , Riñón/anomalías , Radiofármacos , Cirugía Asistida por Computador , Ácido Dimercaptosuccínico de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único , Niño , Femenino , Humanos , Riñón/diagnóstico por imagen , Riñón/cirugía , Enfermedades Renales/diagnóstico por imagen , LaparoscopíaRESUMEN
BACKGROUND: Solitary pulmonary nodule (SPN) still represents a diagnostic challenge. The aim of our study was to evaluate the diagnostic performance of (18)F-fluorodeoxyglucose positron emission tomography-computed tomography in one of the largest samples of small SPNs, incidentally detected in subjects without a history of malignancy (nonscreening population) and undetermined at computed tomography. METHODS: One-hundred and sixty-two small (>0.8 to 1.5 cm) and, for comparison, 206 large nodules (>1.5 to 3 cm) were retrospectively evaluated. Diagnostic performance of (18)F-fluorodeoxyglucose visual analysis, receiver-operating characteristic (ROC) analysis for maximum standardized uptake value (SUVmax), and Bayesian analysis were assessed using histology or radiological follow-up as a golden standard. RESULTS: In 162 small nodules, (18)F-fluorodeoxyglucose visual and ROC analyses (SUVmax = 1.3) provided 72.6% and 77.4% sensitivity and 88.0% and 82.0% specificity, respectively. The prevalence of malignancy was 38%; Bayesian analysis provided 78.8% positive and 16.0% negative posttest probabilities of malignancy. In 206 large nodules (18)F-fluorodeoxyglucose visual and ROC analyses (SUVmax = 1.9) provided 89.5% and 85.1% sensitivity and 70.8% and 79.2% specificity, respectively. The prevalence of malignancy was 65%; Bayesian analysis provided 85.0% positive and 21.6% negative posttest probabilities of malignancy. In both groups, malignant nodules had a significant higher SUVmax (p < 0.0001) than benign nodules. Only in the small group, malignant nodules were significantly larger (p = 0.0054) than benign ones. CONCLUSIONS: (18)F-fluorodeoxyglucose can be clinically relevant to rule in and rule out malignancy in undetermined small SPNs, incidentally detected in nonscreening population with intermediate pretest probability of malignancy, as well as in larger ones. Visual analysis can be considered an optimal diagnostic criterion, adequately detecting a wide range of malignant nodules with different metabolic activity.
Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía de Emisión de Positrones , Radiofármacos , Nódulo Pulmonar Solitario/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Teorema de Bayes , Femenino , Humanos , Hallazgos Incidentales , Masculino , Persona de Mediana Edad , Imagen Multimodal , Valor Predictivo de las Pruebas , Curva ROC , Estudios RetrospectivosRESUMEN
We report a case of thyroid incidentaloma detected by 18F-choline PET/CT. A 66-year-old male patient with a history of prostate cancer underwent a 18F-choline PET/CT for restaging. PET/CT revealed a focal area of increased 18F-choline uptake corresponding to a hypodense nodule in the right lobe of the thyroid. Based on PET/CT findings, the patient underwent a ultrasonography guided fine-needle aspiration biopsy which demonstrated the presence of a benign thyroid nodule.
Asunto(s)
Colina/análogos & derivados , Hallazgos Incidentales , Imagen Multimodal , Tomografía de Emisión de Positrones , Neoplasias de la Tiroides/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Humanos , MasculinoRESUMEN
The future approach of diagnostic imaging in urology follows the technological progress, which made the visualization of in vivo molecular processes possible. From anatomo-morphological diagnostic imaging and through functional imaging molecular radiology is reached. Based on molecular probes, imaging is aimed at assessing the in vivo molecular processes, their physiology and function at cellular level. The future imaging will investigate the complex tumor functioning as metabolism, aerobic glycolysis in particular, angiogenesis, cell proliferation, metastatic potential, hypoxia, apoptosis and receptors expressed by neoplastic cells. Methods for performing molecular radiology are CT, MRI, PET-CT, PET-MRI, SPECT and optical imaging. Molecular ultrasound combines technological advancement with targeted contrast media based on microbubbles, this allowing the selective registration of microbubble signal while that of stationary tissues is suppressed. An experimental study was carried out where the ultrasound molecular probe BR55 strictly bound to prostate tumor results in strong enhancement in the early phase after contrast, this contrast being maintained in the late phase. This late enhancement is markedly significant for the detection of prostatic cancer foci and to guide the biopsy sampling. The 124I-cG250 molecular antibody which is strictly linked to cellular carbonic anhydrase IX of clear cell renal carcinoma, allows the acquisition of diagnostic PET images of clear cell renal carcinoma without biopsy. This WG-250 (RENCAREX) antibody was used as a therapy in metastatic clear cell renal carcinoma. Future advancements and applications will result in early cancer diagnosis, personalized therapy that will be specific according to the molecular features of cancer and leading to the development of catheter-based multichannel molecular imaging devices for cystoscopy-based molecular imaging diagnosis and intervention.
Asunto(s)
Diagnóstico por Imagen/métodos , Técnicas de Diagnóstico Urológico/tendencias , Enfermedades Urológicas/diagnóstico , Diagnóstico por Imagen/tendencias , Predicción , Humanos , Imagen Molecular/métodos , Imagen Molecular/tendencias , Imagen Multimodal/tendencias , Enfermedades Urológicas/metabolismo , Neoplasias Urológicas/irrigación sanguínea , Neoplasias Urológicas/química , Neoplasias Urológicas/diagnósticoRESUMEN
A 40-year-old female patient with suspected multifocal extra-adrenal paraganglioma, on the basis of biochemical, genetic, and conventional imaging data, underwent 18F-FDG, 18F-DOPA and 68Ga DOTANOC PET/CT. FDOPA- and FDG-PET/CT detected a multifocal mediastinal and cervical paraganglioma. 68Ga-DOTANOC PET/CT detected 2 additional lesions compared to the other PET/CT methods. In our case, somatostatin receptor PET/CT with 68Ga-DOTANOC correctly assessed the extent of the disease in a patient with multifocal paraganglioma.
Asunto(s)
Dihidroxifenilalanina/análogos & derivados , Fluorodesoxiglucosa F18 , Compuestos Organometálicos , Paraganglioma Extraadrenal/diagnóstico por imagen , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Femenino , Humanos , Imagen Multimodal , Trazadores RadiactivosRESUMEN
To systematically review published data on the role of positron emission tomography (PET) or PET/computed tomography (PET/CT) using either Carbon-11 ((11)C) or Fluorine-18 ((18)F) choline tracer in tumors other than prostatic cancer. A comprehensive literature search of studies published in PubMed/MEDLINE and Embase databases through January 2012 and regarding (11)C-choline or (18)F-choline PET or PET/CT in patients with tumors other than prostatic cancer was carried out. Fifty-two studies comprising 1800 patients were included and discussed. Brain tumors were evaluated in 15 articles, head and neck tumors in 6, thoracic tumors (including lung and mediastinal neoplasms) in 14, liver tumors (including hepatocellular carcinoma) in 5, gynecologic malignancies (including breast tumors) in 5, bladder and upper urinary tract tumors in 5, and musculoskeletal tumors in 7. Radiolabeled choline PET or PET/CT is useful to differentiate high-grade from low-grade gliomas and malignant from benign brain lesions, to early detect brain tumor recurrences and to guide the stereotactic biopsy sampling. The diagnostic accuracy of radiolabeled choline PET is superior compared to Fluorine-18 fluorodeoxyglucose ((18)F-FDG) PET in this setting. Radiolabeled choline PET or PET/CT seems to be accurate in differential diagnosis between malignant and benign thoracic lesions and in staging lung tumors; nevertheless, a superiority of radiolabeled choline compared to (18)F-FDG has not been demonstrated in this setting, except for the detection of brain metastases. Few but significant studies on radiolabeled choline PET and PET/CT in patients with hepatocellular carcinoma (HCC) and musculoskeletal tumors are reported in the literature. The combination of radiolabeled choline and (18)F-FDG PET increases the detection rate of HCC. The diagnostic accuracy of radiolabeled choline PET or PET/CT seems to be superior compared to (18)F-FDG PET or PET/CT and conventional imaging methods in patients with bone and soft tissue tumors. Limited experience exists about the role of radiolabeled choline PET and PET/CT in patients with head and neck tumors, bladder cancer and gynecologic malignancies including breast cancer.