18FDG-PET is sensitive tool for detection of extracranial tuberculous foci in central nervous system tuberculosis - Preliminary observations from a tertiary care center in northern India.

PURPOSE: To study the role of 18FDG- PET (Flourodeoxyglucose positron emission tomography) in a) determining the extent of cranial and extra-cranial disease and b) diagnosis as well as prognosis of CNS TB (central nervous system tuberculosis) including TBM (tuberculous meningitis). PATIENTS AND METHODS: This prospective observational study (n = 70) was carried out at a tertiary care institute in Northern India from 1.1.2017 to 30.6.2018. Diagnosis of TBM was made according to modified Ahuja's criteria. All patients were evaluated in detail and treated as per standard guidelines. All patients underwent 18FDG-PET scanning of brain and whole body at baseline. RESULTS: Mean age was 35.2 ±â€¯14.8 years. There were 37 men. Majority of patients (n = 47; 67.1%) were below 40 years of age. 43 (61.4%) patients were in stage II TBM. The mean duration of illness was 77 ±â€¯101.9 days. Majority of patients presented with fever (94.3%), headache (90%) and vomiting (84.3%). MRI was abnormal at baseline in 67 (95.7%) of patients, most common abnormalities being meningeal enhancement (68.6%) and tuberculomas (57.1%). PET was abnormal in 66 (95.7%) of patients. All these patients had either lung lesions (n = 62, 88.6%) or lymphadenopathy (n = 61; 87.1%). 18FDG-PET revealed evidence of brain lesions in 52 (74.3%) patients. It revealed vertebral involvement in 19 (27.1%) and genitourinary lesions in 9 (12.9%) patients. PET evidence of lymphadenopathy correlated significantly (p = .04) with good outcome in CNS TB. Conclusion 18FDG-PET does seem to have a promising role in initial evaluation of patients with CNS TB.

3'-Deoxy-3'-18F-Fluorothymidine and 18F-Fluorodeoxyglucose positron emission tomography for the early prediction of response to Regorafenib in patients with metastatic colorectal cancer refractory to all standard therapies.

PURPOSE: The purpose of this study was to evaluate the value of 3'-deoxy-3'-18F-fluorothymidine (18F-FLT) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for early prediction of standard anatomic response and survival outcomes in patients with metastatic colorectal cancer (mCRC) receiving Regorafenib. METHODS: Sixty-eight patients with mCRC refractory to standard cytotoxic chemotherapy were enrolled and received Regorafenib (160 mg/day on days 1-21, following a 7-day break). Standard anatomical response was evaluated every 8 weeks. Both scans were performed before and on day 21 of Regorafenib. RESULTS: Of the 61 patients included in per-protocol analysis, complete response was not observed, but partial response was observed in 8.2% (n = 5), stable disease in 67.2% (n = 41), and progressive disease in 24.6% (n = 15). The objective response rate was 8.2% and disease control rate 75.4%. Five responders (8.2%) and 13 non-responders (21.3%) met the CT and 18F-FLT PET/CT criteria (maximum standardized uptake value decrease ≥ 10.6% for responders). Forty-three (70.5%) exhibited discordant responses on CT and 18F-FLT PET/CT (McNemar test, P < 0.001). At a median follow-up of 8.9 months, median progression-free survival (PFS) and median overall survival (OS) were 3.6 months (95% confidence interval [CI], 3.34-3.80 months) and 8.5 months (95% CI, 6.95-10.10 months), respectively. Comparison of PFS and OS according to 18F-FLT PET/CT response revealed slightly longer PFS (P = 0.015) in responders, but the correlation with OS was not significant. The PET Response Criteria in Solid Tumours (PERCIST) of 18F-FDG PET/CT revealed differences in PFS and OS between partial metabolic response (PMR) and non-PMR (P = 0.048 and P = 0.014, respectively), and between progressive metabolic disease (PMD) and non-PMD (P = 0.189 and P = 0.007, respectively). CONCLUSIONS: Survival outcome was significantly associated with PERCIST using 18F-FDG PET/CT but the change of 18F-FLT uptake was only slightly associated with PFS. 18F-FDG PET/CT can be used as imaging biomarker to predict clinical outcomes early in patients with mCRC receiving Regorafenib.

Change in standardized uptake values in delayed 18F-FDG positron emission tomography images in hepatocellular carcinoma.

Delayed 18F-2-fluoro-2-deoxy-D-glucose (F-FDG) positron emission tomography (PET) imaging has been associated with improved diagnostic yield in several malignancies; however, data on the use of delayed imaging in patients with hepatocellular carcinoma (HCC) is scarce. This study aimed to examine tumoral and background standardized uptake value (SUV) alterations in dual-phase F-FDG PET/computed tomography (CT) imaging.Fifty-two HCC cases underwent dual-time-point F-FDG PET/CT examination where early and delayed images were obtained. The maximum and mean SUVs (SUVmax and SUVmean) of the tumor were determined for both time points. Similarly, the average SUVmean were also determined for background (liver, soft tissue, and spleen). Changes in tumoral and background SUV between early and delayed images were examined.The mean age was 62.0 ±â€Š12.9 years (range, 20-88 years) and the majority of the patients were men (86.5%). Tumor SUVs, both tumor SUVmean and tumor SUVmax, significantly increased at delayed images when compared to early images. In contrast, the average SUVmean for the liver, soft tissue, and spleen significantly decreased at delayed images.A significant increase in tumor SUV in delayed images in contrast to a significant decrease in background SUVs suggests that delayed images in HCC may contribute to diagnostic performance through a potential increase in the contrast between the tumor and background. However, further studies with larger sample sizes including patients with benign lesions and different grades of the disease are warranted to better elucidate the diagnostic contribution as well as the association of delayed imaging values with prognosis.

Usefulness of the maximum standardized uptake value for the diagnosis and staging of patients with cervical cancer undergoing positron emission tomography/computed tomography.

Cervical cancer recently has become more common among younger women in Japan. Diagnosing early-stage cancer is straightforward using cervical cytodiagnosis and histological diagnosis. However, postmenopausal endophytic cervical cancer and skip lesions in cervical adenocarcinoma are difficult to detect. We compared the maximum standardized uptake value (SUVmax) of 18F-fluorodeoxy-glucose positron emission tomography/computed tomography (PET/CT) for primary staging of cervical cancer and evaluated the relationship of the imaging findings to prognosis.This was a retrospective study of 38 patients with cervical cancer who underwent PET/CT. Patients were grouped according to disease stage, and the mean SUVmax, overall survival, and progression-free survival (PFS) were evaluated.The mean SUVmax was significantly different between patients with stage ≤I and ≥II diseases among those with squamous (P > .001) and glandular (P = .023) lesions. With an SUVmax of receiver operating characteristic curves as the optimal cutoff value, the log-rank test for PFS revealed a statistically significant difference between the 2 disease stages (P = .020 and P = .016, respectively).SUVmax is useful to differentiate between stage ≤I and ≥II cervical cancer. SUVmax may be useful for the prognostic evaluation of disease recurrence in patients with cervical cancer.

Focal colorectal uptake in (18)FDG-PET/CT: maximum standard uptake value as a trigger in a semi-automated screening setting.

BACKGROUND: Focal colorectal uptake in (18)FDG-PET/CT may be associated with a malignancy and can be quantified. This provides the basis for an automatic trigger threshold above which cases are flagged for colonoscopic evaluation and below which for individual assessment. PURPOSE: To determine the lowest maximum standard uptake (SUVmax) in colorectal cancer that could be used as a threshold to trigger endoscopic evaluation and to evaluate whether the SUVmax needs to be further normalised to a priori known extrinsic factors. METHODS: The SUVmax was measured in 54 colorectal carcinomas and correlated with gender, age, blood glucose level, injected activity, body mass index and time to scan using t test or correlation coefficients (Pearson or Spearman, according to distribution). RESULTS: There was no correlation between SUVmax and any of the extrinsic factors mentioned above. The lowest SUVmax value was 5 [mean ± SD (range): 11.1 ± 4.8 (5.0-24.6)]. CONCLUSION: In contrast to most other screening techniques, semi-automation in colorectal screening seems possible with PET/CT. This opens the door for further study into the feasibility of automated screening. Independent from extrinsic factors, an SUVmax ≥5.0 in a focal colorectal uptake in (18)FDG-PET/CT should automatically trigger for endoscopic evaluation, if not contraindicated. Cases with SUVmax <5 should be assessed individually before referral for endoscopy. Thus, more interpretation time could be spent on those cases with a lower uptake and more ambiguous diagnosis.

Retrospective quality control review of FDG scans in the imaging sub-study of PALETTE EORTC 62072/VEG110727: a randomized, double-blind, placebo-controlled phase III trial.

PURPOSE: (18)F-Labelled fluorodeoxyglucose (FDG) can detect early changes in tumour metabolism and may be a useful quantitative imaging biomarker (QIB) for prediction of disease stabilization, response and duration of progression-free survival (PFS). Standardization of imaging procedures is a prerequisite, especially in multicentre clinical trials. In this study we reviewed the quality of FDG scans and compliance with the imaging guideline (IG) in a phase III clinical trial. METHODS: Forty-four cancer patients were enroled in an imaging sub-study of a randomized international multicentre trial. FDG scan had to be performed at baseline and 10-14 days after treatment start. The image transmittal forms (ITFs) and Digital Imaging and Communications in Medicine (DICOM) [1] standard headers were analysed for compliance with the IG. Mean liver standardized uptake values (LSUVmean) were measured as recommended by positron emission tomography (PET) Response Criteria in Solid Tumors 1.0 (PERCIST) [2]. RESULTS: Of 88 scans, 81 were received (44 patients); 36 were properly anonymized; 77/81 serum glucose values submitted, all but one within the IG. In 35/44 patients both scans were of sufficient visual quality. In 22/70 ITFs the reported UT differed by >1 min from the DICOM headers (max. difference 1 h 4 min). Based on the DICOM, UT compliance for both scans was 31.4%. LSUVmean was fairly constant for the 11 patients with UT compliance: 2.30 ± 0.33 at baseline and 2.27 ± 0.48 at follow-up (FU). Variability substantially increased for the subjects with unacceptable UT (11 patients): 2.27 ± 1.04 at baseline and 2.18 ± 0.83 at FU. CONCLUSION: The high attrition number of patients due to low compliance with the IG compromised the quantitative assessment of the predictive value for early response monitoring. This emphasizes the need for better regulated procedures in imaging departments, which may be achieved by education of involved personnel or efforts towards regulations. LSUVmean could be monitored to assess quality and compliance in an FDG PET/CT study.

[Comparison of (18)F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography image quality between commercial and in-house supply of FDG radiopharmaceuticals].

OBJECTIVE: PET images are affected by scanner model, reconstruction conditions, injected dose, scan duration, patient health status and FDG radiopharmaceutical supply systems. The present study compares images of 40 patients using commercial and in-house FDG systems with one PET scanner (Aquiduo). METHODS: The PET images were evaluated using the physical indexes of NECpatient, NECdensity and SNRliver proposed by the Japanese guidelines for oncological FDG-PET/CT, and by visual assessment. RESULTS: There were no significant differences in the physical indexes between PET images generated using commercial and in-house FDG. The physical indexes were also acceptable according to the recommended Japanese guidelines. NECdensity was higher when a higher dose/body weight of commercial FDG was injected (correlation coefficient: r=0.576, p<0.001) and lower when BMI was lower and in-house FDG was injected (r=-0.786, p<0.0001). These results suggest that scan duration should be increased if the injected dose of commercial FDG/body weight is <5.5 MBq/kg, and if individuals with BMI >21.4 kg/m(2) are injected with in-house FDG. CONCLUSIONS: Scan duration should be varied depending on FDG supply systems to ensure more accurate image quality and quantitative values during evaluations of response to therapy and prognostic prediction.

Primary tumor maximum standardized uptake value measured on 18F-fluorodeoxyglucose positron emission tomography-computed tomography is a prognostic value for survival in bile duct and gallbladder cancer.

BACKGROUND/AIMS: Few studies have assessed the prognostic value of the primary tumor maximum standardized uptake value (SUV max) measured by 2-[(18)F]-fluoro-2-deoxy-D-glucose PET-CT for patients with bile duct and gallbladder cancer. METHODS: A retrospective analysis of 61 patients with confirmed bile duct and gallbladder cancer who underwent FDG PET-CT in Kangbuk Samsung Medical Center (Seoul, Korea) from April 2008 to April 2011. Prognostic significance of SUV max and other clinicopathological variables was assessed. RESULTS: Twenty-three patients were diagnosed as common bile duct cancer, 17 as hilar bile duct cancer, 12 as intrahepatic bile duct cancer, and nine as gallbladder cancer. In univariate analysis, diagnosis of intrahepatic cholangiocarcinoma and gallbladder cancer, mass forming type, poorly differentiated cell type, nonsurgical treatment, advanced American Joint Committee on Cancer (AJCC) staging and primary tumor SUV max were significant predictors of poor overall survival. In multivariate analysis adjusted for age and sex, primary tumor SUV max (hazard ratio [HR], 4.526; 95% CI, 1.813-11.299), advanced AJCC staging (HR, 4.843; 95% CI, 1.760-13.328), and nonsurgical treatment (HR, 6.029; 95% CI, 1.989-18.271) were independently associated with poor overall survival. CONCLUSIONS: Primary tumor SUV max measured by FDG PET-CT is an independent and significant prognostic factor for overall survival in bile duct and gallbladder cancer.

An operational approach to National Institute on Aging-Alzheimer's Association criteria for preclinical Alzheimer disease.

OBJECTIVE: A workgroup commissioned by the Alzheimer's Association (AA) and the National Institute on Aging (NIA) recently published research criteria for preclinical Alzheimer disease (AD). We performed a preliminary assessment of these guidelines. METHODS: We employed Pittsburgh compound B positron emission tomography (PET) imaging as our biomarker of cerebral amyloidosis, and (18) fluorodeoxyglucose PET imaging and hippocampal volume as biomarkers of neurodegeneration. A group of 42 clinically diagnosed AD subjects was used to create imaging biomarker cutpoints. A group of 450 cognitively normal (CN) subjects from a population-based sample was used to develop cognitive cutpoints and to assess population frequencies of the different preclinical AD stages using different cutpoint criteria. RESULTS: The new criteria subdivide the preclinical phase of AD into stages 1 to 3. To classify our CN subjects, 2 additional categories were needed. Stage 0 denotes subjects with normal AD biomarkers and no evidence of subtle cognitive impairment. Suspected non-AD pathophysiology (SNAP) denotes subjects with normal amyloid PET imaging, but abnormal neurodegeneration biomarker studies. At fixed cutpoints corresponding to 90% sensitivity for diagnosing AD and the 10th percentile of CN cognitive scores, 43% of our sample was classified as stage 0, 16% stage 1, 12 % stage 2, 3% stage 3, and 23% SNAP. INTERPRETATION: This cross-sectional evaluation of the NIA-AA criteria for preclinical AD indicates that the 1-3 staging criteria coupled with stage 0 and SNAP categories classify 97% of CN subjects from a population-based sample, leaving only 3% unclassified. Future longitudinal validation of the criteria will be important.

Adaptación del módulo de 18FDG para la preparación de una disolución inyectable de [18F] fluoruro sódico de conformidad con la Farmacopea Americana (USP 32) y Europea (PhEur 6) / Adaptation of the 18FDG module for the preparation of a sodium fluoride [18F] injection solution in agreement with the United States (USP 32) and European Pharmacopeia (PhEur 6)

Objetivos. Establecer un procedimiento automatizado para la preparación de la disolución inyectable de [18F] NaF utilizando los recursos disponibles en nuestro laboratorio para la preparación de 18FDG, analizando la repercusión del acondicionamiento de la columna de atrapamiento del ion fluoruro sobre las características del producto final. Material y método. Se modificó la secuencia de un módulo de síntesis de 18FDG automatizado de manera que el ion fluoruro procedente del ciclotrón se atrapa en resina de intercambio aniónico y se eluye con cloruro sódico 0,9%. La disolución final se dosifica y autoclava en envase final en equipo automatizado. Dentro del proceso, se estudiaron tres protocolos diferentes de acondicionamiento de columna. Se realizaron los controles de calidad descritos en USP 32 y PhEur 6, añadiendo el control de etanol como disolvente residual y los controles de calidad de la disolución a las 8 h de la preparación. Resultados. La activación de los cartuchos de resina con etanol y agua presenta una atrapamiento del ion fluoruro > 95% y pH en torno a 7, por lo que es el procedimiento de acondicionamiento de elección. La concentración de etanol se mantuvo < 5.000 ppm. Los controles efectuados a las 8 h indicaban que la disolución mantenía las especificaciones de USP 32 y PhEur 6. Conclusiones. Se describe un método automatizado sencillo, económico y reproducible, de preparación de una disolución inyectable de 18F-fluoruro sódico al alcance de cualquier centro con equipamiento convencional para síntesis y control de calidad de 18FDG(AU)

Objective. To establish an automated procedure for the preparation of sodium fluoride 18F injection using the resources available in our laboratory for the preparation of 18FDG and to analyze the repercussion of the conditioning column of the fluoride ion entrapment on the characteristics of the final product. Material and method. The sequence of an 18FDG synthesis module prepared so that it traps the fluoride ion from the cyclotron in ion-exchange resin diluted with 0.9% sodium chloride. The final solution was dosified and sterilized in a final vial in an automatized dispensing module. Three different column conditioning protocols within the process were tested. Quality controls were run according to USP 32 and EurPh 6, adding control of ethanol levels of residual solvent and quality controls of the solution at 8 h post-preparation. Results. Activation of the resin cartridges with ethanol and water was the chosen procedure, with fluoride ion trapping > 95% and pH around 7. Ethanol levels were < 5.000 ppm. Quality controls at 8 h indicated that the solution was in compliance with the USP 32 and EurPh 6 specifications. Conclusion. This is an easy, low-cost, reliable automated method for sodium fluoride preparation in PET facilities with existing equipment for 18FDG synthesis and quality control(AU)

The radioprotection management of a PET department with a cyclotron and radiopharmacy laboratory, in accordance with Italian legislation.

The possibility of setting up a positron emission tomography (PET) facility with a cyclotron and radiopharmaceutical laboratory in situ, at a feasible price and in a very restricted space, has led to a steady increase both in the use of the PET technique in diagnostic clinical routine imaging and in the number of cyclotrons for drug production. Owing to the progress made in the PET procedures, it is now possible to have not only a highly innovative system of diagnostic examination, with a remarkable improvement in the diagnostic quality and patient care, but also a considerable increase in the number of daily examinations. In this paper, the authors show how the acquired know-how, with respect to radioprotection, has applied to the planning, running and management of the PET/CT unit, installed in the Imaging Diagnostic Department of the Policlinico Tor Vergata (PTV), at Tor Vergata University, Rome.

Investigation of staff finger doses during quality control of FDG production.

The European Pharmacopoeia and Good Manufacturing Practice define a number of quality control tests that must be performed prior to the release of FDG. The aim of this study is to determine the finger dose received while performing these tests. The finger dose received by four staff members was measured using Unfors NED monitors placed at the tip of the index finger of both hands during routine quality control. A total of 18 readings were obtained for the dispensing of the quality control samples, bubble point test, thin layer chromatography, gas chromatography, endotoxin test, Kryptofix test, multi-channel analyzer test, pH and high performance liquid chromatography. The average total dose for the completion of all tests was 1,508 µSv for the left hand and 846 µSv for the right hand. As a result of the bubble point test, 54% and 43% of the total dose is received for the left and right hand, respectively. The pH test, high performance liquid chromatography and dispensing of the QC sample also contribute significantly to the total dose. Staff may need to be defined as classified radiation workers as a result of the finger dose received during routine quality control. Automation of the bubble point test and dispensing should be considered during the planning and design of any new cyclotron production facility.

[Adaptation of the (18)FDG module for the preparation of a sodium fluoride [(18)F] injection solution in agreement with the United States (USP 32) and European Pharmacopeia (PhEur 6)]. / Adaptación del módulo de (18)FDG para la preparación de una disolucióninyectable de [(18)F] fluoruro sódico de conformidad con la Farmacopea Americana(USP 32) y Europea (PhEur 6).

OBJECTIVE: To establish an automated procedure for the preparation of sodium fluoride (18)F injection using the resources available in our laboratory for the preparation of (18)FDG and to analyze the repercussion of the conditioning column of the fluoride ion entrapment on the characteristics of the final product. MATERIAL AND METHOD: The sequence of an (18)FDG synthesis module prepared so that it traps the fluoride ion from the cyclotron in ion-exchange resin diluted with 0.9% sodium chloride. The final solution was dosified and sterilized in a final vial in an automatized dispensing module. Three different column conditioning protocols within the process were tested. Quality controls were run according to USP 32 and EurPh 6, adding control of ethanol levels of residual solvent and quality controls of the solution at 8 h post-preparation. RESULTS: Activation of the resin cartridges with ethanol and water was the chosen procedure, with fluoride ion trapping > 95% and pH around 7. Ethanol levels were < 5.000 ppm. Quality controls at 8 h indicated that the solution was in compliance with the USP 32 and EurPh 6 specifications. CONCLUSION: This is an easy, low-cost, reliable automated method for sodium fluoride preparation in PET facilities with existing equipment for (18)FDG synthesis and quality control.

Standardization of fluorine-18 manufacturing processes: new scientific challenges for PET.

In [(18)F]fluoride chemistry, the minute amounts of radioactivity taking part in a radiolabeling reaction are easily outnumbered by other reactants. Surface areas become comparably larger and more influential than in standard fluorine chemistry, while leachables, extractables, and other components that normally are considered small impurities can have a considerable influence on the efficiency of the reaction. A number of techniques exist to give sufficient (18)F-tracer for a study in a pre-clinical or clinical system, but the chemical and pharmaceutical understanding has significant gaps when it comes to scaling up or making the reaction more efficient. Automation and standardization of [(18)F]fluoride PET tracers is a prerequisite for reproducible manufacturing across multiple PET centers. So far, large-scale, multi-site manufacture has been established only for [(18)F]FDG, but several new tracers are emerging. In general terms, this transition from small- to large-scale production has disclosed several scientific challenges that need to be addressed. There are still areas of limited knowledge in the fundamental [(18)F]fluoride chemistry. The role of pharmaceutical factors that could influence the (18)F-radiosynthesis and the gaps in precise chemistry knowledge are discussed in this review based on a normal synthesis pattern.

Is there a common SUV threshold in oncological FDG PET/CT, at least for some common indications? A retrospective study.

PURPOSE: We retrospectively compared the maximum standard uptake value (SUVmax) of FDG PET in four different sites to evaluate whether a common diagnostic SUVmax threshold may exist in these tumor locations. We further postulate that the SUVmax thresholds are higher in thoracic lesions than in extrathoracic lesions. MATERIAL AND METHODS: N = 143 patients in four subgroups underwent a FDG PET/CT: a) 42 patients for solitary pulmonary nodules (SPNs) characterization with b) respective mediastinal lymph nodes (LNs), c) 65 patients for LN staging of head and neck cancer, and d) 36 cancer patients diagnosed with adrenal lesions. Receiver operating characteristics of SUVmax values were evaluated. RESULTS: The SUVmax were statistically significantly greater in malignant than in benign lesions. For SPNs and mediastinal LNs, a SUVmax > 3.6 each resulted in a sensitivity of 81% and 87%, and a specificity of 94% and 89%. For cervical LNs and adrenal glands, a SUVmax > 2.2 each showed a sensitivity of 98% and 100%, and a specificity of 83% and 93%. CONCLUSION: A common SUVmax threshold did not exist in the four studied subgroups. The variable FDG uptake in SPNs and mediastinal LNs are associated with the high prevalence of inflammation/infection within the chest. Similar SUVmax thresholds however may exist for extrathoracic regions where the prevalence of inflammation/infection is low.

Variations in clinical PET/CT operations: results of an international survey of active PET/CT users.

UNLABELLED: This study gathered information about clinical PET/CT operations worldwide to help guide discussions on the use and standardization of clinical PET/CT. METHODS: A Web-based survey of PET/CT users was initiated in November 2009 through e-mail advertising using Academy of Molecular Imaging databases. Recipients were asked 58 questions related to demographics (e.g., location, number of PET/CT systems, and staffing), PET/CT operations and use, and variations in (18)F-FDG oncology imaging protocols. RESULTS: The responders were from centers in the Americas (71%), Europe (22%), Asia-Pacific (6%), and Middle East (1%), with most responding sites representing public health care institutions (60%). PET/CT systems were most frequently installed in nuclear medicine departments (59%). Of the sites operating a PET/CT system, 16% had 10 y or more of stand-alone PET experience. About 40% of all sites operated at least 2 PET/CT systems. PET/CT was most frequently used for applications in torso or whole-body oncology (87%), radiation therapy planning (4%), cardiology (4%), and neurology (5%). The average interval of fasting before an (18)F-FDG PET/CT examination was 7 ± 3 h (range, 4-12 h). Blood glucose levels were measured at 99% of sites, but acceptable maximal glucose levels varied substantially (an upper limit of 200 mg/dL was applied at >50% of the institutions). A weight-based radioactivity dose injection was performed at 44% of sites. The mean (18)F-FDG activity injected was 390 MBq (range, 110-585 MBq) for 3-dimensional PET of a 75-kg patient. The mean uptake time was 64 ± 14 min (range, 20-90 min). Split protocols involving patient repositioning and adapted imaging parameters were used at 51% of sites. Only 41% used patient positioning aids. Intravenous or oral CT contrast material was used at 52% of sites in up to 25% of patients. Most sites (90%) measured maximum standardized uptake value as an index of tissue glucose use. Only 62% of sites provided a fully integrated PET/CT report. CONCLUSION: An international survey among clinical PET/CT users revealed significant variations in standard (18)F-FDG PET/CT protocols. This finding illustrates the need for continuous training and ongoing standardization in an effort to optimize PET/CT in oncology.

Comparison of Limulus amebocyte lysates with the United States pharmacopeial pyrogen test and the portable test system for radiopharmaceuticals.

Radiopharmaceuticals play an important role in modern nuclear medicine, and 18F-FDG (2-[18F] fluoro-2-deoxy-D-glucose) is the most frequently used in imaging examinations today. The pyrogen test represents an important parameter for the quality of radiopharmaceuticals since most of them, 18F-FDG included, are injectable solutions. However, the standard test proposed by the U.S. Pharmacopeia using limulus amebocyte lysates takes too long (about 1 h). An alternative test is the Portable Test System, which takes no more than 15 min. In order to compare both tests, 10 batches of 18F-FDG produced in the Nuclear Engineering Institute, Rio de Janeiro, Brazil, were analyzed. The results showed that in 40% of the samples analyzed, different results were found. From the total analyzed, 20% showed totally diverging results, and 80% demonstrated partial similarity. These differences have a great impact in the choice of the test used for radiopharmaceutical injectable solutions and the importance of validation tests before the implementation in the daily routine.

A simple method for the quality control of [(18)F]FDG.

Most automated synthesis modules produce [(18)F]FDG within half an hour, but the quality control involving up to three separate methods and three different analytical systems is time consuming. The use of HPLC, TLC, and GC for the quality control of [(18)F]FDG is both time consuming and expensive (high purchase costs). Presented here is a method using a single HPLC system for all three analyses.

The SUVmax of 18F-FDG PET correlates with histological grade in endometrial cancer.

OBJECTIVES: The objectives of this study were to assess the maximum standardized uptake value (SUVmax) of F-fluorodeoxyglucose (F-FDG) by a primary tumor of endometrial cancer with the use of positron emission tomography/computed tomography (PET/CT) and to assess its association with the clinical importance of the disease. METHODS: F-fluorodeoxyglucose PET/CT scan was performed on 44 participants within 2 weeks before surgery. F-fluorodeoxyglucose uptake was quantified by calculating the SUVmax. The distribution of cases that scored positive for each of the biological parameters examined was correlated with the SUVmax of the F-FDG PET/CT and the glucose transporter-1 expression status obtained by immunohistochemistry. RESULTS: The mean SUVmax of the primary endometrial cancer tumors was 17.6 (range, 3.04-34.74). There were significant correlations between the SUVmax of the primary tumor and the International Federation of Gynecology and Obstetrics (FIGO) grade (P < 0.001), maximum tumor size (P < 0.001), and glucose transporter-1 expression (P < 0.001). Furthermore, multivariate analysis showed that the FIGO grade was most significantly identified as a relation factor of SUVmax (> or =17.6) for endometrial cancer (P = 0.017). The present findings indicate that a significant relationship was seen between the SUVmax and the FIGO grade in endometrial cancer. CONCLUSION: We propose that the primary tumor's SUVmax obtained from F-FDG PET/CT may be associated with aggressive biological characteristics in endometrial cancer.