Nuclear_Medicine RSS : Gourt

Statewide :: Pennsylvania :: The Doctor Job

Looking for a job in a big city? Even if you've heard that a market is "saturated", wecan help! Many job openings for physicians may be hidden and unavailable unless you knowwhere to

Statewide :: Virginia :: The Doctor Job

Looking for a job in a big city? Even if you've heard that a market is "saturated", we can help! Many job openings for physicians may be hidden and unavailable unless you know where to look. An excellent

Statewide :: Texas :: The Doctor Job

Statewide :: Ohio :: The Doctor Job

Statewide :: New York :: The Doctor Job

Statewide :: New Jersey :: The Doctor Job

Statewide :: Maryland :: The Doctor Job

Statewide :: Indiana :: The Doctor Job

Statewide :: Illinois :: The Doctor Job

Statewide :: Georgia :: The Doctor Job

Statewide :: Florida :: The Doctor Job

Statewide :: District of Columbia :: The Doctor Job

Statewide :: Connecticut :: The Doctor Job

Statewide :: California :: The Doctor Job

Statewide :: Arizona :: The Doctor Job

Intravesical alpha-radioimmunotherapy with 213Bi-anti-EGFR-mAb defeats human bladder carcinoma in xenografted nude mice.

Related Articles Intravesical alpha-radioimmunotherapy with 213Bi-anti-EGFR-mAb defeats human bladder carcinoma in xenografted nude mice. J Nucl Med. 2009 Oct;50(10):1700-8 Authors: Pfost B, Seidl C, Autenrieth M, Saur D, Bruchertseifer F, Morgenstern A, Schwaiger M, Senekowitsch-Schmidtke R Transurethral resection of urothelial carcinoma often results in tumor recurrence due to disseminated tumor cells. Therefore, new therapeutic strategies are urgently needed. The aim of this study was to establish an orthotopic human bladder carcinoma mouse model using the epidermal growth factor receptor (EGFR)-overexpressing bladder carcinoma cell line EJ28 and to compare therapeutic efficacy of intravesically instilled alpha-particle-emitting (213)Bi-anti-EGFR-monoclonal antibody (mAb) with mitomycin C. METHODS: Female Swiss nu/nu mice were intravesically inoculated with luciferase-transfected EJ28 human bladder carcinoma cells after the induction of urothelial lesions by electrocautery. At different time points after cell inoculation, mice were treated intravesically with (213)Bi-anti-EGFR-mAb, mitomycin C, or unlabeled anti-EGFR-mAb. Tumor development and therapeutic response were evaluated via bioluminescence imaging. RESULTS: Mice without therapy and those treated with unlabeled anti-EGFR-mAb reached a median survival of 41 d and 89 d, respectively. Mice that underwent therapy with 0.925 MBq of (213)Bi-anti-EGFR-mAb 1 h, 7 d, or 14 d after cell instillation survived more than 300 d in 90%, 80%, and 40% of the cases, respectively. Therapy with 0.37 MBq 1 h or 7 d after tumor cell inoculation resulted in survival of more than 300 d in 90% and 50% of mice, respectively. Mitomycin C treatment after 1 h and 7 d prolonged survival to more than 300 d in 40% and 50%, respectively; however, treatment turned out to be nephrotoxic. In contrast, no signs of nephrotoxicity could be observed after (213)Bi-anti-EGFR-mAb treatment. CONCLUSION: The study suggests that radioimmunotherapy using intravesically instilled (213)Bi-anti-EGFR-mAb is a promising option for treatment of bladder cancer in patients. PMID: 19793735 [PubMed - indexed for MEDLINE]

Weight-based, low-dose pediatric whole-body PET/CT protocols.

Related Articles Weight-based, low-dose pediatric whole-body PET/CT protocols. J Nucl Med. 2009 Oct;50(10):1570-7 Authors: Alessio AM, Kinahan PE, Manchanda V, Ghioni V, Aldape L, Parisi MT Adult PET/CT acquisition protocols need to be modified for pediatric imaging to minimize the radiation dose while maintaining diagnostic utility. We developed pediatric PET/CT acquisition protocols customized to patient weight and estimated the dosimetry and cancer risk of these low-dose protocols to communicate basic imaging risks. METHODS: Protocols were developed for whole-body (18)F-FDG imaging of patients in PET mode with a weight-based injected activity (5.3 MBq/kg) and acquisition times (3-5 min/field of view) and for CT for attenuation correction and localization with a weight-based tube current ranging from 10 to 40 mAs. Patients were categorized on the basis of the Broselow-Luten color-coded weight scale. Dosimetry and radiation-induced cancer risk for the PET and CT acquisition in each category were derived from mean patient sizes and the interpolation of factors from accepted patient models. RESULTS: Whole-body pediatric PET/CT protocols require the customization of PET-acquisition settings and task-specific selection of CT technique. The proposed weight-based protocols result in an approximate effective dose ranging from 8.0 mSv for a 9-kg patient up to 13.5 mSv for a 63-kg patient. The radiation dose from the proposed protocols is 20%-50% (depending on patient weight), the dose from PET/CT protocols that use a fixed CT technique of 120 mAs and 120 kVp. The approximate, conservative estimate of additional lifetime attributable risk (LAR) of cancer incidence for females using the proposed protocols was approximately 3 in 1,000, with a variation of 18% across patient categories. For males, the additional LAR of cancer incidence was approximately 2 in 1,000, with a variation of 16% across categories. CONCLUSION: Low-dose PET/CT protocols for 11 patient weight categories were developed. The proposed protocols offer an initial set of acquisition parameters for pediatric PET/CT. The use of multiple categories allows for the continued refinement of dose-reduction parameters to minimize dose while maintaining image quality across the range of pediatric patient sizes. PMID: 19793734 [PubMed - indexed for MEDLINE]

MICoE areas of focus for 2010.

Related Articles MICoE areas of focus for 2010. J Nucl Med. 2009 Oct;50(10):15N Authors: VanBrocklin HF PMID: 19793733 [PubMed - indexed for MEDLINE]

Priorities over the next year: achieving our strategic vision together.

Related Articles Priorities over the next year: achieving our strategic vision together. J Nucl Med. 2009 Oct;50(10):14N, 20N Authors: Pappas V PMID: 19793732 [PubMed - indexed for MEDLINE]

ACNP and ACNM announce merger.

Related Articles ACNP and ACNM announce merger. J Nucl Med. 2009 Oct;50(10):13N Authors: Harolds J PMID: 19793731 [PubMed - indexed for MEDLINE]

131I-6beta-iodomethyl-19-norcholesterol SPECT/CT for primary aldosteronism patients with inconclusive adrenal venous sampling and CT results.

Related Articles 131I-6beta-iodomethyl-19-norcholesterol SPECT/CT for primary aldosteronism patients with inconclusive adrenal venous sampling and CT results. J Nucl Med. 2009 Oct;50(10):1631-7 Authors: Yen RF, Wu VC, Liu KL, Cheng MF, Wu YW, Chueh SC, Lin WC, Wu KD, Tzen KY, Lu CC, The 2 main causes of primary aldosteronism (PA) are aldosterone-producing adenoma (APA) and idiopathic adrenal hyperplasia (IAH). Dexamethasone-suppression (131)I-6beta-iodomethyl-19-norcholesterol (NP-59) adrenal scintigraphy can assess the functioning of the adrenal cortex. This study evaluated the diagnostic usefulness of NP-59 SPECT/CT in differentiating APA from IAH and in predicting postadrenalectomy clinical outcome for PA patients who had inconclusive adrenal venous sampling (AVS) and CT results. METHODS: We retrospectively reviewed the 31 adrenal lesions of 27 patients (age range, 33-71 y; mean age +/- SD, 50.4 +/- 10.9 y) who had been clinically confirmed (by saline infusion and captopril tests) to have PA, had inconclusive CT and AVS test results, and had undergone NP-59 imaging before adrenalectomy. The accuracy of NP-59 imaging was determined by comparison with histopathologic findings. RESULTS: NP-59 SPECT/CT gave us 18 true-positive, 3 false-positive, 6 true-negative, and 4 false-negative results. Compared with planar imaging, SPECT/CT significantly improved diagnostic accuracy and prognostic predicting ability (P = 0.0390 and P = 0.0141, respectively). The NP-59 results were negative for 7 of the 23 patients with unilateral adrenal lesions, and none of these 7 patients had shown postsurgical clinical improvement. CONCLUSION: NP-59 SPECT/CT is an effective imaging tool for differentiating APA from IAH in PA patients whose CT and AVS results are inconclusive. Our results suggest that patients with presurgically negative NP-59 results should be treated medically and that noninvasive NP-59 SPECT/CT may be suited for use as the first lateralization modality after CT in patients with clinically confirmed PA. PMID: 19759122 [PubMed - indexed for MEDLINE]

In vivo optical imaging of cellular inflammatory response in granuloma formation using fluorescence-labeled macrophages.

Related Articles In vivo optical imaging of cellular inflammatory response in granuloma formation using fluorescence-labeled macrophages. J Nucl Med. 2009 Oct;50(10):1676-82 Authors: Eisenblätter M, Ehrchen J, Varga G, Sunderkötter C, Heindel W, Roth J, Bremer C, Wall A Near-infrared imaging such as fluorescence reflectance imaging (FRI) and fluorescence-mediated tomography (FMT) yields high signal-to-noise ratios (SNRs) and should thus be well suited for cell-tracking studies. Extravasation of monocytes or macrophages (Ms) is one of the earliest events in inflammation. The purpose of this study was to assess whether FRI and FMT allow for the visualization and quantification of early inflammatory processes by tracing the migration of fluorescence-labeled murine Ms in a cutaneous granuloma model. METHODS: Ms were labeled with a membrane-selective carbocyanine dye (1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyanine iodide [DiR]). Cellular viability and function (nitric oxide production, phagocytosis, adherence) were assessed in vitro. Local inflammation was induced in mice by the subcutaneous injection of polyacrylamide gel pellets including or excluding a strong inflammatory stimulus (lipopolysaccharide). Labeled Ms were injected intravenously, and FRI and FMT were performed up to 7 d. SNRs were calculated for the pellets, and the 3-dimensional distribution of Ms was assessed using FMT. Cells were harvested from gel pellets and analyzed by flow cytometry. RESULTS: DiR labeling did not affect cell viability or cell function. FRI revealed the migration of labeled Ms into gel pellets and the homing of Ms to different body compartments. The lipopolysaccharide-containing pellets exhibited significantly higher SNRs than did pellets without lipopolysaccharide. FMT showed that Ms distributed mainly in the periphery of the pellets. The cellular infiltrates extracted from the harvested pellets revealed the presence of approximately 10%-23% DiR-positive Ms-expressing typical markers, confirming the transendothelial migration of injected Ms. CONCLUSION: The tagging of Ms with DiR allows the noninvasive tracking of inflammatory cells for several days in vivo. FRI and FMT are versatile techniques to monitor and quantify cellular inflammatory responses in vivo. PMID: 19759121 [PubMed - indexed for MEDLINE]

Multispectral fluorescence imaging.

Related Articles Multispectral fluorescence imaging. J Nucl Med. 2009 Oct;50(10):1563-6 Authors: Zhou L, El-Deiry WS Multispectral fluorescence imaging (MSFI) is a rapidly growing field with broad applications in both preclinical and clinical settings. Application of this novel technology in small-animal imaging and microscopy produces enhanced sensitivity and reliable quantification and resolves multiple simultaneous signals. MSFI flow cytometry can quantify multiple fluorescent parameters with morphologic or subcellular spatial details on millions of cells. MSFI has the potential to improve the accuracy of disease detection or differentiation and intrasurgical metastatic diagnosis, guide neurosurgeries, and monitor treatment response. PMID: 19759119 [PubMed - indexed for MEDLINE]

Clinical imaging characteristics of the positron emission mammography camera: PEM Flex Solo II.

Related Articles Clinical imaging characteristics of the positron emission mammography camera: PEM Flex Solo II. J Nucl Med. 2009 Oct;50(10):1666-75 Authors: MacDonald L, Edwards J, Lewellen T, Haseley D, Rogers J, Kinahan P We evaluated a commercial positron emission mammography (PEM) camera, the PEM Flex Solo II. This system comprises two 6 x 16.4 cm detectors that scan together covering up to a 24 x 16.4 cm field of view (FOV). There are no specific standards for testing this detector configuration. We performed several tests important to breast imaging, and we propose tests that should be included in standardized testing of PEM systems. METHODS: We measured spatial resolution, uniformity, counting- rate linearity, recovery coefficients, and quantification accuracy using the system's software. Image linearity and coefficient of variation at the edge of the FOV were also characterized. Anecdotal examples of clinical patient data are presented. RESULTS: The spatial resolution was 2.4 mm in full width at half maximum for image planes parallel to the detector faces. The background variability was approximately 5%, and quantification accuracy and recovery coefficients varied within the FOV. Positioning linearity began at approximately 13 mm from the edge of the detector housing. The coefficient of variation was significantly higher close to the edge of the FOV because of limited sensitivity in these image planes. CONCLUSION: A reconstructed spatial resolution of 2.4 mm represented a significant improvement over conventional whole-body PET scanners and should reduce the lower threshold on lesion size and tracer uptake for detection in the breast. Limited-angle tomography and a lack of data corrections result in spatially variable quantitative results. PEM acquisition geometry limits sampling statistics at the chest-wall edge of the camera, resulting in high variance in that portion of the image. Example patient images demonstrate that lesions can be detected at the chest-wall edge despite variance artifacts, and fine structure is visualized routinely throughout the FOV in the focal plane. The PEM Flex camera should enable the functional imaging of breast cancer earlier in the disease process than whole-body PET. PMID: 19759118 [PubMed - indexed for MEDLINE]

18F-FDG PET/CT identifies patients at risk for future vascular events in an otherwise asymptomatic cohort with neoplastic disease.

Related Articles 18F-FDG PET/CT identifies patients at risk for future vascular events in an otherwise asymptomatic cohort with neoplastic disease. J Nucl Med. 2009 Oct;50(10):1611-20 Authors: Rominger A, Saam T, Wolpers S, Cyran CC, Schmidt M, Foerster S, Nikolaou K, Reiser MF, Bartenstein P, Hacker M Our objective was to evaluate the association of arterial (18)F-FDG uptake and calcifications in large arteries as detected by (18)F-FDG PET/CT with the subsequent occurrence of vascular events in otherwise asymptomatic cancer patients. METHODS: Clinical follow-up information was obtained for 932 cancer patients examined with whole-body (18)F-FDG PET/CT (median follow-up time, 29 mo). Among this cohort, 279 patients had died from their oncologic disease. In 15 of 932 patients (1.6%), a vascular event, defined as ischemic stroke, myocardial infarction, or revascularization, was registered. The maximal standardized uptake value (SUV) was divided by the blood-pool SUV, yielding a target-to-background ratio (TBR) for each arterial segment. The mean TBR as well as a calcified plaque sum score per patient were calculated in the major vessels: ascending, descending, and abdominal aorta, aortic arch, as well as iliac and carotid arteries. RESULTS: A significant correlation was observed between mean TBR and calcified plaque sum (P < 0.001). Although calcified plaque sum significantly correlated with all conventional risk factors for vascular events, mean TBR correlated only with age, the male sex, and hypertension. The Cox regression hazard model identified a mean TBR >or= 1.7 and a calcified plaque sum >or= 15 as independent predictors for the occurrence of a vascular event. Patients with both mean TBR and calcified plaque sum above these thresholds were identified as having the highest risk for a future vascular event. However, a mean TBR >or= 1.7 had greater prognostic value than did a calcified plaque sum >or= 15. CONCLUSION: In a large cohort of cancer patients, increased (18)F-FDG uptake in major arteries emerged as the strongest predictor of a subsequent vascular event. Concomitant severe vascular calcifications seemed to impart a particularly high risk. Given the small event rate in the present study, larger, prospective trials of patients without cancer are required to substantiate these promising results. PMID: 19759117 [PubMed - indexed for MEDLINE]

Melanin-targeted preclinical PET imaging of melanoma metastasis.

Related Articles Melanin-targeted preclinical PET imaging of melanoma metastasis. J Nucl Med. 2009 Oct;50(10):1692-9 Authors: Ren G, Miao Z, Liu H, Jiang L, Limpa-Amara N, Mahmood A, Gambhir SS, Cheng Z Dialkylamino-alkyl-benzamides possess an affinity for melanin, suggesting that labeling of such benzamides with (18)F could potentially produce melanin-targeted PET probes able to identify melanotic melanoma metastases in vivo with high sensitivity and specificity. METHODS: In this study, N-[2-(diethylamino)ethyl]-4-(18)F-fluorobenzamide ((18)F-FBZA) was synthesized via a 1-step conjugation reaction. The sigma-receptor binding affinity of (19)F-FBZA was determined along with the in vitro cellular uptake of radiofluorinated (18)F-FBZA in B16F10 cells. In vivo distribution and small-animal PET studies were conducted on mice bearing B16F10 melanoma, A375M amelanotic melanoma, and U87MG tumors, and comparative studies were performed with (18)F-FDG PET in the melanoma models. RESULTS: In vitro, uptake of (18)F-FBZA was significantly higher in B16F10 cells treated with l-tyrosine (P < 0.001). In vivo, (18)F-FBZA displayed significant tumor uptake; at 2 h, 5.94 +/- 1.83 percentage injected dose (%ID) per gram was observed in B16F10 tumors and only 0.75 +/- 0.09 %ID/g and 0.56 +/- 0.13 %ID/g was observed in amelanotic A375M and U87MG tumors, respectively. Lung uptake was significantly higher in murine lungs bearing melanotic B16F10 pulmonary metastases than in normal murine lungs (P < 0.01). Small-animal PET clearly identified melanotic lesions in both primary and pulmonary metastasis B16F10 tumor models. Coregistered micro-CT with small-animal PET along with biopsies further confirmed the presence of tumor lesions in the mouse lungs. CONCLUSION: (18)F-FBZA specifically targets primary and metastatic melanotic melanoma lesions with high tumor uptake and may have translational potential. PMID: 19759116 [PubMed - indexed for MEDLINE]

A biomathematical modeling approach to central nervous system radioligand discovery and development.

Related Articles A biomathematical modeling approach to central nervous system radioligand discovery and development. J Nucl Med. 2009 Oct;50(10):1715-23 Authors: Guo Q, Brady M, Gunn RN The development of a successful PET or SPECT molecular imaging probe is a complex, time-consuming, and expensive process that suffers from high attrition. To address this problem, we have developed a biomathematical modeling approach that aims to predict the in vivo performance of radioligands directly from in silico/in vitro data. METHODS: The method estimates the in vivo nondisplaceable and total uptake of a ligand in a target tissue using a standard input function and a 1-tissue-compartment model with a parsimonious parameter set (influx rate constant K(1), efflux rate constant k(2), and binding potential BP(ND)) whose values are predicted from in silico/in vitro data including lipophilicity, molecular volume, free fraction in plasma and tissue, target density, affinity, perfusion, capillary surface area, and apparent aqueous volume in plasma and tissue. The coefficient of variation of the BP(ND) (%COV[BP(ND)]) metric, derived from Monte Carlo simulations, is used to estimate the in vivo performance of candidate compounds. A total of 28 compounds for 10 targets was evaluated using our method to predict their in vivo performance and validated against measured in vivo PET data in the Yorkshire/Danish Landrace pig. RESULTS: The predicted K(1), k(2), and BP(ND) values were generally consistent with the values estimated from in vivo PET data. The model resulted in small %COV[BP(ND)] values for widely accepted good ligands such as (11)C-flumazenil (2.02%) and (11)C-raclopride (2.55%), whereas higher values resulted from poor ligands such as (11)C-(R)-PK11195 (13.34%). Of 4 candidates for the GlyT1 transporter, the model selected (11)C-GSK931145 (2.11%) as the most promising ligand, which was consistent with historical decisions made on the in vivo PET data. CONCLUSION: A biomathematical modeling approach has the potential to predict the in vivo performance of ligands from in silico/in vitro data and aid in the development of molecular imaging probes. PMID: 19759115 [PubMed - indexed for MEDLINE]

Salivary gland side effects commonly develop several weeks after initial radioactive iodine ablation.

Related Articles Salivary gland side effects commonly develop several weeks after initial radioactive iodine ablation. J Nucl Med. 2009 Oct;50(10):1605-10 Authors: Grewal RK, Larson SM, Pentlow CE, Pentlow KS, Gonen M, Qualey R, Natbony L, Tuttle RM Salivary gland side effects (SSEs) can be a source of significant morbidity in thyroid cancer patients receiving radioactive iodine (RAI) for remnant ablation or therapy. However, the incidence, time course, and ultimate resolution of SSEs that develop in the first few months after a single administered activity of RAI for remnant ablation has not be adequately defined. METHODS: We retrospectively reviewed the clinical records of patients after RAI remnant ablation (RRA) to determine the incidence of salivary gland-related side effects reported within the first year of RRA, the dose-response relationship between administered activity and specific SSEs, and the incidence of specific SSEs based on the method of preparation for remnant ablation (recombinant human thyroid-stimulating hormone [rhTSH] vs. traditional thyroid hormone withdrawal [THW]). RESULTS: SSEs were reported within the first year of RAI ablation in 39% of a cohort of 262 patients (66% women, 93% papillary thyroid cancer; median dose, 5,217 MBq [141 mCi]). Persistent side effects were noted after a median of 7 y in 5% or less of the entire cohort. However, when side effects developed in patients during the first year, the incidence of persistence of the symptom at last follow-up ranged from 5% to 13%. A statistically significant dose response was seen between administered activity of RAI and development of salivary gland swelling (P = 0.001, logistic dose-response curve) but not with dry mouth (P = 0.63), altered taste (P = 0.27), or salivary gland pain (P = 0.152). SSEs developed in 14% of patients receiving administered activities of 1,110 MBq (30 mCi); administered activities of 2,775 MBq (75 mCi) or more were associated with symptoms in 40% of patients (P = 0.046). Despite receiving a statistically higher administered activity (5,661 +/- 2,997 MBq [153 +/- 81 mCi] for THW vs. 4,958 +/- 2,294 MBq [134 +/- 62 mCi] for rhTSH), THW was associated with a lower rate of salivary gland swelling than the rhTSH preparation (20% vs. 10%; P = 0.017), without differences in the development of dry mouth, altered taste, or salivary gland pain. CONCLUSION: Although SSEs occurred in 39% of patients after routine RRA, they were usually transient, so that the overall incidence of persistent side effects at a median follow-up of 7 y was only 5%. Even though the risk for persistent side effects is rather small, these data do emphasize the need to select patients carefully for RRA who are thought to be at moderate to high risk for recurrence and to use the minimally effective dose of RAI activity, in an attempt to maximize the potential benefit while minimizing the risk for adverse events for an individual patient. PMID: 19759114 [PubMed - indexed for MEDLINE]

Observer variation in interpreting 18F-FDG PET/CT findings for lymphoma staging.

Related Articles Observer variation in interpreting 18F-FDG PET/CT findings for lymphoma staging. J Nucl Med. 2009 Oct;50(10):1594-7 Authors: Hofman MS, Smeeton NC, Rankin SC, Nunan T, O'Doherty MJ Many studies demonstrate a high accuracy for PET in staging lymphoma, but few assess observer variation. This study quantified agreement for staging lymphoma with PET/CT. METHODS: The PET/CT images of 100 patients with lymphoma who had been referred for staging were reviewed by 3 experienced observers, with 2 observers reviewing each series a second time. Ann Arbor stage and individual nodal and extranodal regions were assessed. Weighted kappa (kappa(w)) and intraclass correlation coefficient were used to compare ratings. RESULTS: Intra- and interobserver agreement was high for Ann Arbor stage (kappa(w) = 0.79-0.91), number of nodal regions involved (intraclass correlation coefficient, 0.83-0.93), and presence of extranodal disease (kappa = 0.74-0.86). High agreement was also observed for all nodal regions (kappa(w) > 0.60) except hilar (kappa(w) = 0.56-0.82) and infraclavicular (kappa(w) = 0.14-0.55). Lower agreement was observed for bowel involvement (kappa(w) = 0.37-0.71). CONCLUSION: Experienced observers had a high level of agreement using PET/CT for lymphoma staging, supporting its use as a robust noninvasive staging tool. Further research is needed to evaluate observer variability for restaging during and after chemotherapy. PMID: 19759113 [PubMed - indexed for MEDLINE]

Functional images reflect aggressiveness of endometrial carcinoma: estrogen receptor expression combined with 18F-FDG PET.

Related Articles Functional images reflect aggressiveness of endometrial carcinoma: estrogen receptor expression combined with 18F-FDG PET. J Nucl Med. 2009 Oct;50(10):1598-604 Authors: Tsujikawa T, Yoshida Y, Kudo T, Kiyono Y, Kurokawa T, Kobayashi M, Tsuchida T, Fujibayashi Y, Kotsuji F, Okazawa H The grade of histologic differentiation is one of the most important prognostic factors in patients with endometrial carcinoma and postoperative staging. The aim of this study was to investigate whether 16alpha-(18)F-fluoro-17beta-estradiol ((18)F-FES) and (18)F-FDG PET reflect clinicopathologic features in patients with endometrial tumors. METHODS: A total of 22 patients with endometrial adenocarcinoma and 9 with endometrial hyperplasia (mean age, 56.0 +/- 15.3 y) underwent (18)F-FES PET for estrogen receptor imaging and (18)F-FDG PET. Regional values of tracer uptake were evaluated using standardized uptake value (SUV) and the SUV ratio of (18)F-FDG to (18)F-FES. The accuracy for predicting tumor aggressiveness defined as high-risk carcinoma (International Federation of Gynecology and Obstetrics [FIGO] stage >or= Ic or histologic grade >or= 2), low-risk carcinoma (FIGO stage

Single 20-second acquisition of deep-inspiration breath-hold PET/CT: clinical feasibility for lung cancer.

Related Articles Single 20-second acquisition of deep-inspiration breath-hold PET/CT: clinical feasibility for lung cancer. J Nucl Med. 2009 Oct;50(10):1579-84 Authors: Torizuka T, Tanizaki Y, Kanno T, Futatsubashi M, Yoshikawa E, Okada H, Ouchi Y This study was designed to compare tumor (18)F-FDG uptake between a single 20-s acquisition of deep-inspiration breath-hold PET/CT and free-breathing PET/CT for lung cancer. METHODS: Before the clinical study, a phantom study was performed to determine the optimum breath-hold time for the PET scan. We studied 47 patients with lung cancer who underwent free-breathing PET/CT with the standard clinical protocol, followed by deep-inspiration breath-hold PET/CT of the thorax. In breath-hold PET/CT, the patients were asked to hold their breath in deep inspiration for 10 s during the CT scan and for 20 s during the PET scan. Maximum tumor (18)F-FDG standardized uptake value (SUVmax) was measured in free-breathing PET and breath-hold PET, and the percentage difference between these 2 values was calculated. RESULTS: Breath-hold PET showed a significant increase in SUVmax, as compared with free-breathing PET (8.26 +/- 4.59 vs. 11.25 +/- 7.24, P < 0.0001). The mean difference in SUVmax was 39.5% +/- 43.4%, and the range was 2.9%-248.3%. The difference in SUVmax was significant when compared between tumors in the upper lung (n = 22) and tumors in the lower lung (n = 25) (24.4% +/- 17.7% vs. 52.9% +/- 54.3%, P = 0.0077). The mean tumor size of the group with a high SUVmax difference (n = 13) was significantly smaller than that of the group with a low SUVmax difference (n = 34) (2.45 +/- 0.87 cm vs. 3.21 +/- 1.22 cm, P = 0.043), using a cutoff of 39.5%. CONCLUSION: The single 20-s acquisition of breath-hold PET/CT enabled more precise measurement of SUVmax, especially in the lower lung field and for small tumors, which may be affected by respiratory motion. This technique is feasible in the clinical setting and requires only a minor increase in examination time. PMID: 19759111 [PubMed - indexed for MEDLINE]

Three-step, "one-pot" radiosynthesis of 6-fluoro-3,4-dihydroxy-L-phenylalanine by isotopic exchange.

Related Articles Three-step, "one-pot" radiosynthesis of 6-fluoro-3,4-dihydroxy-L-phenylalanine by isotopic exchange. J Nucl Med. 2009 Oct;50(10):1724-9 Authors: Wagner FM, Ermert J, Coenen HH The (18)F-labeled aromatic amino acid 6-fluoro-3,4-dihydroxy-L-phenylalanine (6-(18)F-fluoro-L-DOPA) is widely used as a radiopharmaceutical in neurologic and oncologic PET. In this study, a novel approach to the preparation of carrier-added (CA) 6-(18)F-fluoro-L-DOPA in 3 radiosynthesis steps was developed and evaluated; in this approach, direct nucleophilic (18)F fluorination of a protected amino acid derivative was used. The method currently used for the routine preparation of 6-(18)F-fluoro-L-DOPA by electrophilic labeling is limited to the production of small amounts of activity at high costs. Alternative syntheses based on the advantage of large-scale production of nucleophilic (18)F-fluoride, however, either have resulted in insufficient enantiomeric purity or are difficult to automate because of the complexity of the necessary multiple steps. METHODS: An isotopic exchange reaction on the precursor (2S,5S)-tert-butyl-5-(4-benzyloxy-2-fluoro-5-formylbenzyl)-2-tert-butyl-3-methyl-4-oxoimidazolidine-1-carboxylate was used. The formyl group served as the activating group in the (18)F-for-(19)F exchange with tetrabutylammonium bicarbonate for anion activation in N,N-dimethylformamide. The intermediate was converted to a hydroxy group by Baeyer-Villiger oxidation with meta-chloroperbenzoic acid. After final deprotection with hydrobromic acid, CA 6-(18)F-fluoro-L-DOPA was isolated by high-performance liquid chromatography. RESULTS: The precursor was obtained by an 11-step organic synthesis. The optimized isotopic (18)F exchange proceeded with a radiochemical yield of about 50%. The complete preparation and isolation of CA 6-(18)F-fluoro-L-DOPA thus far are possible with a radiochemical yield of about 22%, within a synthesis time of 105 min, and at a much higher specific activity than with the electrophilic method. The enantiomeric excess of the desired L-isomer was greater than 96%. CONCLUSION: The pathway to 6-(18)F-fluoro-L-DOPA by isotopic exchange not only is more efficient but also is suited to automation as a "one-pot" procedure. PMID: 19759110 [PubMed - indexed for MEDLINE]

Detection of aggressive primary prostate cancer with 11C-choline PET/CT using multimodality fusion techniques.

Related Articles Detection of aggressive primary prostate cancer with 11C-choline PET/CT using multimodality fusion techniques. J Nucl Med. 2009 Oct;50(10):1585-93 Authors: Piert M, Park H, Khan A, Siddiqui J, Hussain H, Chenevert T, Wood D, Johnson T, Shah RB, Meyer C The aim of the study was to assess whether (11)C-choline PET/CT could identify high-risk primary adenocarcinoma of the prostate. METHODS: (11)C-choline PET/CT and transpelvic MRI were performed in 14 patients with untreated localized primary adenocarcinoma of the prostate, followed by radical prostatectomy as a form of primary monotherapy within 14 d of in vivo imaging. To allow accurate coregistration of whole-mount histology with in vivo imaging, additional ex vivo MR images of the prostatectomy specimen were obtained. Nonlinear 3-dimensional image deformations were used for registrations of PET/CT, MRI, and histology. Volumes of interest from tumor and benign tissue were defined on the basis of histology and were transferred into coregistered (11)C-choline PET/CT volumes to calculate the mean (T((mean))/B) and maximum (T((max))/B) ratio of tumor to benign prostate background. On the basis of MIB-1/Ki-67 expression in tumor tissues represented on a tissue microarray, we assessed whether (11)C-choline uptake correlated with local Gleason score and tumor proliferation. RESULTS: Histology confirmed 42 tumor nodules with Gleason scores between 3 + 2 and 4 + 4, with volumes ranging from 0.03 to 12.6 cm(3). T((mean))/B (P < 0.01) and T((max))/B (P < 0.001) ratios were significantly increased in high-Gleason score (>or=4 + 3) lesions versus 3 + 4 and lower disease but failed to distinguish between 3 + 4 disease versus 3 + 3 and lower. T((mean))/B and T((max))/B ratios were significantly increased in tumors with an MIB-1/Ki-67 labeling index greater than or equal to 5% (P < 0.01). CONCLUSION: On the basis of our preliminary data using ratios of tumor to benign prostate background, (11)C-choline preferentially identified aggressive primary prostate cancer. PMID: 19759109 [PubMed - indexed for MEDLINE]

2-18F-Fluoropropionic acid as a PET imaging agent for prostate cancer.

Related Articles 2-18F-Fluoropropionic acid as a PET imaging agent for prostate cancer. J Nucl Med. 2009 Oct;50(10):1709-14 Authors: Pillarsetty N, Punzalan B, Larson SM There is a high interest in developing an (18)F-labeled PET tracer that can aid in diagnosis and therapy monitoring of prostate cancer. In the current study, we have evaluated the potential of 2-(18)F-fluoropropionic acid ((18)F-FPA) as a PET tracer for imaging prostate cancer. METHODS: (18)F-FPA was synthesized starting from methyl-2-bromopropionate. Small-animal PET studies were performed on mice with CWR22rv1, PC-3, DU-145, and LNCaP prostate xenografts, and comparison of imaging characteristics of (18)F-FPA with (18)F-FDG uptake is reported. Biodistribution studies with (18)F-FPA were performed on mice with CWR22rv1 xenografts and compared with (14)C-acetate. RESULTS: (18)F-FPA was synthesized in 44% overall radiochemical yield (decay-corrected). Small-animal PET studies revealed that (18)F-FPA can delineate both androgen-dependent and androgen-independent prostate xenografts with high tumor-to-background ratios. Comparative imaging studies demonstrate the superior performance of (18)F-FPA over (18)F-FDG for imaging prostate cancer, with excellent tumor-to-background contrast. Biodistribution studies show that tumor uptake of the tracer was 5.52 +/- 0.35, 5.53 +/- 0.42, 5.74 +/- 0.54, and 5.34 +/- 0.19 percentage injected dose (%ID) per gram at 1, 2, 3, and 4 h, respectively, after injection. The %ID/g values for (18)F-FPA and (14)C-acetate 1 h after tail vein injection were 7.08 +/- 0.80 and 0.36 +/- 0.08 in tumor, and the corresponding tumor-to-muscle ratios were 1.94 and 2.06, respectively. CONCLUSION: The data presented here indicate that (18)F-FPA accumulates in prostate cancers with high tumor-to-background ratios. (18)F-FPA has potential for use in the clinical diagnosis of prostate cancer in humans. PMID: 19759108 [PubMed - indexed for MEDLINE]

Imaging tumor phenotype: 1 plus 1 is more than 2.

Imaging tumor phenotype: 1 plus 1 is more than 2. J Nucl Med. 2009 Oct;50(10):1567-9 Authors: Mankoff DA, Dehdashti F PMID: 19759107 [PubMed - indexed for MEDLINE]

Safety of radial arterial catheterization in PET research subjects.

Related Articles Safety of radial arterial catheterization in PET research subjects. J Nucl Med. 2009 Oct;50(10):1742 Authors: Everett BA, Oquendo MA, Abi-Dargham A, Nobler MS, Devanand DP, Lisanby SH, Mann JJ, Parsey RV PMID: 19759106 [PubMed - indexed for MEDLINE]

Repeatability of 18F-FDG PET in a multicenter phase I study of patients with advanced gastrointestinal malignancies.

Related Articles Repeatability of 18F-FDG PET in a multicenter phase I study of patients with advanced gastrointestinal malignancies. J Nucl Med. 2009 Oct;50(10):1646-54 Authors: Velasquez LM, Boellaard R, Kollia G, Hayes W, Hoekstra OS, Lammertsma AA, Galbraith SM (18)F-FDG PET is often used to monitor tumor response in multicenter oncology clinical trials. This study assessed the repeatability of several semiquantitative standardized uptake values (mean SUV [SUV(mean)], maximum SUV [SUV(max)], peak SUV [SUV(peak)], and the 3-dimensional isocontour at 70% of the maximum pixel value [SUV(70%)]) as measured by repeated baseline (18)F-FDG PET studies in a multicenter phase I oncology trial. METHODS: Double-baseline (18)F-FDG PET studies were acquired for 62 sequentially enrolled patients. Tumor metabolic activity was assessed by SUV(mean), SUV(max), SUV(peak), and SUV(70%). The effect on SUV repeatability of compliance with recommended image-acquisition guidelines and quality assurance (QA) standards was assessed. Summary statistics for absolute differences relative to the average of baseline values and repeatability analysis were performed for all patients and for a subgroup that passed QA, in both a multi- and a single-observer setting. Intrasubject precision of baseline measurements was assessed by repeatability coefficients, intrasubject coefficients of variation (CV), and confidence intervals on mean baseline differences for all SUV parameters. RESULTS: The mean differences between the 2 SUV baseline measurements were small, varying from -2.1% to 1.9%, and the 95% confidence intervals for these mean differences had a maximum half-width of about 5.6% across the SUV parameters assessed. For SUV(max), the intrasubject CV varied from 10.7% to 12.8% for the QA multi- and single-observer datasets and was 16% for the full dataset. The 95% repeatability coefficients ranged from -28.4% to 39.6% for the QA datasets and up to -34.3% to 52.3% for the full dataset. CONCLUSION: Repeatability results of double-baseline (18)F-FDG PET scans were similar for all SUV parameters assessed, for both the full and the QA datasets, in both the multi- and the single-observer settings. Centralized quality assurance and analysis of data improved intrasubject CV from 15.9% to 10.7% for averaged SUV(max). Thresholds for metabolic response in the multicenter multiobserver non-QA settings were -34% and 52% and in the range of -26% to 39% with centralized QA. These results support the use of (18)F-FDG PET for tumor assessment in multicenter oncology clinical trials. PMID: 19759105 [PubMed - indexed for MEDLINE]

Quantitative analysis of myocardial perfusion SPECT anatomically guided by coregistered 64-slice coronary CT angiography.

Related Articles Quantitative analysis of myocardial perfusion SPECT anatomically guided by coregistered 64-slice coronary CT angiography. J Nucl Med. 2009 Oct;50(10):1621-30 Authors: Slomka PJ, Cheng VY, Dey D, Woo J, Ramesh A, Van Kriekinge S, Suzuki Y, Elad Y, Karlsberg R, Berman DS, Germano G Sequential testing by coronary CT angiography (CTA) and myocardial perfusion SPECT (MPS) obtained on stand-alone scanners may be needed to diagnose coronary artery disease in equivocal cases. We have developed an automated technique for MPS-CTA registration and demonstrate its utility for improved MPS quantification by guiding the coregistered physiologic (MPS) with anatomic CTA information. METHODS: Automated registration of MPS left ventricular (LV) surfaces with CTA coronary trees was accomplished by iterative minimization of voxel differences between presegmented CTA volumes and motion-frozen MPS data. Studies of 35 sequential patients (26 men; mean age, 67 +/- 12 y) with 64-slice coronary CTA, MPS, and available results of the invasive coronary angiography performed within 3 mo were retrospectively analyzed. Three-dimensional coronary vessels and CTA slices were extracted and fused with quantitative MPS results mapped on LV surfaces and MPS coronary regions. Automatically coregistered CTA images and extracted trees were used to correct the MPS contours and to adjust the standard vascular region definitions for MPS quantification. RESULTS: Automated coregistration of MPS and coronary CTA had the success rate of 96% as assessed visually; the average errors were 4.3 +/- 3.3 mm in translation and 1.5 +/- 2.6 degrees in rotation on stress and 4.2 +/- 3.1 mm in translation and 1.7 +/- 3.2 degrees in rotation on rest. MPS vascular region definition was adjusted in 17 studies, and LV contours were adjusted in 11 studies using coregistered CTA images as a guide. CTA-guided myocardial perfusion analysis, compared with standard MPS analysis, resulted in improved area under the receiver-operating-characteristic (ROC) curves for the detection of right coronary artery (RCA) and left circumflex artery (LCX) lesions (0.84 +/- 0.08 vs. 0.70 +/- 0.11 for LCX, P = 0.03, and 0.92 +/- 0.05 vs. 0.75 +/- 0.09 for RCA, P = 0.02). CONCLUSION: Software image coregistration of stand-alone coronary CTA and MPS obtained on separate scanners can be performed rapidly and automatically, allowing CTA-guided contour and vascular territory adjustment on MPS for improved quantitative MPS analysis. PMID: 19759104 [PubMed - indexed for MEDLINE]

NEMA NU4-2008 image quality performance report for the microPET focus 120 and for various transmission and reconstruction methods.

Related Articles NEMA NU4-2008 image quality performance report for the microPET focus 120 and for various transmission and reconstruction methods. J Nucl Med. 2009 Oct;50(10):1730-8 Authors: Bahri MA, Plenevaux A, Warnock G, Luxen A, Seret A This work aimed to evaluate the image quality and accuracy of attenuation and scatter corrections provided with the microPET Focus 120 scanner using the National Electrical Manufacturers Association NU4-2008 image quality phantom. METHODS: Attenuation correction was obtained from transmission measurements using either a (68)Ge or a (57)Co point source. Fully corrected emission images were reconstructed using Fourier rebinning (FORE) and filtered backprojection (FBP). For attenuation data obtained with the (57)Co source, fully corrected emission images were also reconstructed using FORE and 2-dimensional (2D) ordered-subset expectation maximization (OSEM), 3-dimensional (3D) filtered backprojection (3DRP), 3D OSEM, and 3D maximum a posteriori methods. The mean activity, the coefficients of variation (COVs) of the uniform slices, the recovery coefficients (RCs) for hot rods, and the spillover ratio (SOR) for nonemitting water and air compartments were measured. RESULTS: For (57)Co-based attenuation correction, the mean activity value differed by less than 3% from the true activity. Measuring the attenuation with (68)Ge resulted in lower reconstructed activity and higher COV. On the basis of (57)Co measurements, the SORs for air and water nonemitting compartments were the closest to zero for attenuation correction. The RC measured on emission images corrected for attenuation but not for scatter did not show any significant difference linked to the transmission method. However, higher RCs were noted for transmission measurement with (68)Ge in coincidence with windowing when emission data were corrected for attenuation and scatter. This resulted from a lower mean value in the uniform area. 2D and 3DRP reconstruction methods showed little effect on the mean activity value, whereas iterative 3D methods gave 7% higher values. Higher RCs were found with iterative reconstruction than with FBP and 3DRP. However, the SOR seemed to be optimal with FBP. SORs were higher with iterative methods and decreased with the number of iterations. CONCLUSION: For studies of small rodents with the Focus 120, (57)Co transmission seems to be the most suitable method for attenuation correction. FORE and 2D reconstruction methods appear to be a good compromise between overall image quality and reconstruction time: OSEM provides the largest contrasts, but FBP provides superior attenuation and scatter correction. PMID: 19759103 [PubMed - indexed for MEDLINE]

The 18F-FDG PET cingulate island sign and comparison to 123I-beta-CIT SPECT for diagnosis of dementia with Lewy bodies.

Related Articles The 18F-FDG PET cingulate island sign and comparison to 123I-beta-CIT SPECT for diagnosis of dementia with Lewy bodies. J Nucl Med. 2009 Oct;50(10):1638-45 Authors: Lim SM, Katsifis A, Villemagne VL, Best R, Jones G, Saling M, Bradshaw J, Merory J, Woodward M, Hopwood M, Rowe CC Neuroimaging is increasingly used to supplement the clinical diagnosis of dementia with Lewy bodies (DLB) by showing reduced occipital metabolism and perfusion and reduced striatal dopaminergic innervation. We aimed to optimize the interpretation of (18)F-FDG PET images for differentiating DLB from Alzheimer disease (AD) and to compare the results with dopamine transporter imaging using (123)I-beta-carbomethoxy-3ss-(4-iodophenyl)tropane ((123)I-beta-CIT) SPECT. METHODS: Fourteen subjects with a clinical diagnosis of DLB and 10 with AD underwent both (18)F-FDG PET and (123)I-beta-CIT SPECT. Four DLB and 1 AD diagnoses were subsequently confirmed at autopsy. Diagnostic accuracy was calculated for visual interpretation by 3 readers of standard 3-plane and stereotactic surface projection (18)F-FDG PET images, receiver-operating-characteristic analysis of regional (18)F-FDG uptake, and a cutoff value for the striatal-to-occipital binding ratio of beta-CIT defined by receiver-operating-characteristic analysis. RESULTS: Visual interpretation of 3-plane (18)F-FDG PET images had a sensitivity of 83% and specificity of 93% for DLB, slightly higher than the results with the stereotactic surface projection images. Regionally, hypometabolism in the lateral occipital cortex had the highest sensitivity (88%), but relative preservation of the mid or posterior cingulate gyrus (cingulate island sign) had the highest specificity (100%). Region-of-interest analysis revealed that occipital hypometabolism and relative preservation of the posterior cingulate both had a sensitivity of 77% and specificity of 80%. beta-CIT achieved 100% accuracy and greater effect size than did (18)F-FDG PET (Cohen d = 4.1 vs. 1.9). CONCLUSION: Both (18)F-FDG PET and (123)I-beta-CIT SPECT appear useful for the diagnosis of DLB, although the latter provides more robust results. The cingulate island sign may enhance the specificity of (18)F-FDG PET. PMID: 19759102 [PubMed - indexed for MEDLINE]

Radiolabeled humanized anti-CD3 monoclonal antibody visilizumab for imaging human T-lymphocytes.

Related Articles Radiolabeled humanized anti-CD3 monoclonal antibody visilizumab for imaging human T-lymphocytes. J Nucl Med. 2009 Oct;50(10):1683-91 Authors: Malviya G, D'Alessandria C, Bonanno E, Vexler V, Massari R, Trotta C, Scopinaro F, Dierckx R, Signore A Visilizumab is an IgG(2) humanized monoclonal antibody (mAb) characterized by non-FcgammaR binding and specific to the CD3 antigen, expressed on more than 95% of circulating resting T-lymphocytes and on activated T-lymphocytes homing in inflamed tissues. We hypothesized that the use of a radiolabeled anti-CD3 antibody might serve as a diagnostic tool for imaging T-cell traffic and lymphocytic infiltration of tissues and organs affected by autoimmune diseases. Here we describe the results of in vitro and animal experiments with (99m)Tc-succinimidyl-6-hydrazinonicotinate hydrochloride (SHNH)-visilizumab. METHODS: For mAb labeling, we used a 2-step method with a heterobifunctional linker SHNH. Several titrations were performed to obtain the best labeling efficiency. In vitro quality controls included stability assay, cysteine challenge, sodium dodecyl sulfate polyacrylamide gel electrophoresis, binding assay, and immunoreactivity assay. In vivo studies by high-resolution images were performed at 6 and 24 h after the injection of (99m)Tc-SHNH-visilizumab. These included cell-targeting experiments in BALB/c mice xenografted subcutaneously with an increasing number of HuT78 cells in the leg and displaced with an excess of cold antibody. We also studied irradiated severe combined immunodeficient (SCID) mice reconstituted with human peripheral blood mononuclear cells (hPBMCs) and injected with (99m)Tc-labeled visilizumab or control mAb. After dynamic imaging for 3 h, major organs were removed, counted, and processed for immunohistologic examination. RESULTS: Visilizumab was labeled with HYNIC with high labeling efficiency (>90%) and high specific activity (SA; 10,360-11,100 MBq/mg), with retained biochemical integrity and in vitro binding activity to CD3-positive cells. The in vivo targeting experiment showed a proportional increase of specific uptake with the number of injected cells, both at 6 and at 24 h, and the in vivo competition study demonstrated more than 60% decreased uptake after an excess of unlabeled antibody. In SCID mice, hPBMCs in different tissues were detected by (99m)Tc-labeled visilizumab and confirmed by histology. CONCLUSION: Visilizumab can be efficiently labeled with (99m)Tc with high efficiency and SA and could be a valuable tool for the study of human T-lymphocyte trafficking and lymphocytic infiltration of tissues and organs. PMID: 19759100 [PubMed - indexed for MEDLINE]

18F-FDG PET/CT for image-guided and intensity-modulated radiotherapy.

Related Articles 18F-FDG PET/CT for image-guided and intensity-modulated radiotherapy. J Nucl Med. 2009 Oct;50(10):1655-65 Authors: Ford EC, Herman J, Yorke E, Wahl RL Advances in technology have allowed extremely precise control of radiation dose delivery and localization within a patient. The ability to confidently delineate target tumor boundaries, however, has lagged behind. (18)F-FDG PET/CT, with its ability to distinguish metabolically active disease from normal tissue, may provide a partial solution to this problem. Here we review the current applications of (18)F-FDG PET/CT in a variety of disease sites, including non-small cell lung cancer, head and neck cancer, and pancreatic adenocarcinoma. This review focuses on the use of (18)F-FDG PET/CT to aid in planning radiotherapy and the associated benefits and challenges. We also briefly consider novel radiopharmaceuticals that are beginning to be used in the context of radiotherapy planning. PMID: 19759099 [PubMed - indexed for MEDLINE]

Shaping change, advancing quality...one patient at a time.

Related Articles Shaping change, advancing quality...one patient at a time. J Nucl Cardiol. 2009 Nov 5; Authors: PMID: 19890686 [PubMed - as supplied by publisher]