20 research outputs found
Impact of fasting on F-18-fluorocholine gastrointestinal uptake and detection of lymph node metastases in patients with prostate cancer
BACKGROUND: (18)F-fluorocholine PET/CT is used to detect lymph node metastases in prostate cancer patients. Physiological (18)F-fluorocholine in the gastrointestinal tract, especially in the intestines, may interfere with the detection of malignant lymph nodes. Fasting is frequently proposed in literature; however, scientific support is lacking. This study aims to determine the impact of fasting on (18)F-fluorocholine uptake in the gastrointestinal tract. METHODS: Eighty patients were studied, 40 fasted for at least 6 h prior to (18)F-fluorocholine administration while the other 40 did not fast. (18)F-fluorocholine uptake pattern and intensity were evaluated in the intestine near the abdominal aorta and four regions near the iliac arteries. (18)F-fluorocholine intensity was also measured in the liver, pancreas, stomach and spleen. FINDINGS: No statistically significant differences were found in (18)F-fluorocholine uptake in the gastrointestinal tract between the fasting and non-fasting group. CONCLUSIONS: Fasting for 6 h has no effect on (18)F-fluorocholine uptake in the gastrointestinal tract. Therefore, no effects on the detection of malignant lymph nodes are expected, and fasting is not recommended in our opinion
International Conference on Advances in Radiation Oncology (ICARO): Outcomes of an IAEA Meeting
The IAEA held the International Conference on Advances in Radiation Oncology (ICARO) in Vienna on 27-29 April 2009. The Conference dealt with the issues and requirements posed by the transition from conventional radiotherapy to advanced modern technologies, including staffing, training, treatment planning and delivery, quality assurance (QA) and the optimal use of available resources. The current role of advanced technologies (defined as 3-dimensional and/or image guided treatment with photons or particles) in current clinical practice and future scenarios were discussed
Detection and localization of early- and late-stage cancers using platelet RNA
Cancer patients benefit from early tumor detection since treatment outcomes are more favorable for less advanced cancers. Platelets are involved in cancer progression and are considered a promising biosource for cancer detection, as they alter their RNA content upon local and systemic cues. We show that tumor-educated platelet (TEP) RNA-based blood tests enable the detection of 18 cancer types. With 99% specificity in asymptomatic controls, thromboSeq correctly detected the presence of cancer in two-thirds of 1,096 blood samples from stage I–IV cancer patients and in half of 352 stage I–III tumors. Symptomatic controls, including inflammatory and cardiovascular diseases, and benign tumors had increased false-positive test results with an average specificity of 78%. Moreover, thromboSeq determined the tumor site of origin in five different tumor types correctly in over 80% of the cancer patients. These results highlight the potential properties of TEP-derived RNA panels to supplement current approaches for blood-based cancer screening
Air-Stable n-Channel Organic Transistors Based on a Soluble C84 Fullerene Derivative
Air-stable n-channel organic transistors are fabricated using a newly synthesized soluble fullerene derivative. The airstable nature of this molecule allows the realization of complementary circuits under ambient conditions without encapsulation. As shown in the figure, the I-V characteristics of the devices are retained even after exposure to air for a week. To the best of our knowledge, this is the first demonstration of an air-stable electron-transporting fullerene-based molecule
(18)F-DCFPyL PET/CT in the Detection of Prostate Cancer at 60 and 120 Minutes: Detection Rate, Image Quality, Activity Kinetics, and Biodistribution
There is increasing interest in PET/CT with prostate-specific membrane antigen (PSMA) tracers for imaging of prostate cancer because of the higher detection rates of prostate cancer lesions than with PET/CT with choline. For Ga-68-PSMA-11 tracers, late imaging at 180 min after injection instead of imaging at 45-60 min after injection improves the detection of prostate cancer lesions. For (18)F-DCFPyL, improved detection rates have recently been reported in a small pilot study. In this study, we report the effects of PET/CT imaging at 120 min after injection of (18)F-DCFPyL in comparison to images acquired at 60 min after injection in a larger clinical cohort of 66 consecutive patients with histopathologically proven prostate cancer. Methods: Images were acquired 60 and 120 min after injection of (18)F-DCFPyL. We report the positive lesions specified for anatomic locations (prostate, seminal vesicles, local lymph nodes, distant lymph nodes, bone, and others) at both time points by visual analysis, the image quality at both time points, and a semiquantitative analysis of the tracer activity in both prostate cancer lesions as well as normal tissues at both time points. Results: Our data showed a significantly increasing uptake of (18)F-DCFPyL between 60 and 120 min after injection in 203 lesions characteristic for prostate cancer (median, 10.78 vs. 12.86, P <0.001, Wilcoxon signed-rank test). By visual analysis, 38.5% of all patients showed more lesions using images at 120 min after injection than using images at 60 min after injection, and in 9.2% a change in TNM staging was found. All lesions seen on images 60 min after injection were also visible on images 120 min after injection. A significantly better mean signal-tonoise ratio of 11.93 was found for images acquired 120 min after injection (P <0.001, paired t test; signal-to-noise ratio at 60 min after injection, 11.15). Conclusion: (18)F-DCFPyL PET/CT images at 120 min after injection yield a higher detection rate of prostate cancer characteristic lesions than images at 60 min after injection. Further studies are needed to elucidate the best imaging time point for (18)F-DCFPyL
(18)F-DCFPyL PET/CT in the Detection of Prostate Cancer at 60 and 120 Minutes:Detection Rate, Image Quality, Activity Kinetics, and Biodistribution
There is increasing interest in PET/CT with prostate-specific membrane antigen (PSMA) tracers for imaging of prostate cancer because of the higher detection rates of prostate cancer lesions than with PET/CT with choline. For Ga-68-PSMA-11 tracers, late imaging at 180 min after injection instead of imaging at 45-60 min after injection improves the detection of prostate cancer lesions. For (18)F-DCFPyL, improved detection rates have recently been reported in a small pilot study. In this study, we report the effects of PET/CT imaging at 120 min after injection of (18)F-DCFPyL in comparison to images acquired at 60 min after injection in a larger clinical cohort of 66 consecutive patients with histopathologically proven prostate cancer. Methods: Images were acquired 60 and 120 min after injection of (18)F-DCFPyL. We report the positive lesions specified for anatomic locations (prostate, seminal vesicles, local lymph nodes, distant lymph nodes, bone, and others) at both time points by visual analysis, the image quality at both time points, and a semiquantitative analysis of the tracer activity in both prostate cancer lesions as well as normal tissues at both time points. Results: Our data showed a significantly increasing uptake of (18)F-DCFPyL between 60 and 120 min after injection in 203 lesions characteristic for prostate cancer (median, 10.78 vs. 12.86, P <0.001, Wilcoxon signed-rank test). By visual analysis, 38.5% of all patients showed more lesions using images at 120 min after injection than using images at 60 min after injection, and in 9.2% a change in TNM staging was found. All lesions seen on images 60 min after injection were also visible on images 120 min after injection. A significantly better mean signal-tonoise ratio of 11.93 was found for images acquired 120 min after injection (P <0.001, paired t test; signal-to-noise ratio at 60 min after injection, 11.15). Conclusion: (18)F-DCFPyL PET/CT images at 120 min after injection yield a higher detection rate of prostate cancer characteristic lesions than images at 60 min after injection. Further studies are needed to elucidate the best imaging time point for (18)F-DCFPyL
Insight into the Effect of Water on the Methanol-to-Olefins Conversion in H-SAPO-34 from Molecular Simulations and in Situ Microspectroscopy
The role of water in the methanol-to-olefins (MTO) process over H-SAPO-34 has been elucidated by a combined theoretical and experimental approach, encompassing advanced molecular dynamics simulations and in situ microspectroscopy. First-principles calculations at the molecular level point out that water competes with methanol and propene for direct access to the Bronsted acid sites. This results in less efficient activation of these molecules, which are crucial for the formation of the hydrocarbon pool. Furthermore, lower intrinsic methanol reactivity toward methoxide formation has been observed. These observations are in line with a longer induction period observed from in situ UV-vis microspectroscopy experiments. These experiments revealed a slower and more homogeneous discoloration of H-SAPO-34, while in situ confocal fluorescence microscopy confirmed the more homogeneous distribution and larger amount of MTO intermediates when cofeeding water. As such, it is shown that water induces a more efficient use of the H-SAPO-34 catalyst crystals at the microscopic level. The combined experimental-theoretical approach gives a profound insight into the role of water in the catalytic process at the molecular and single-particle level. © 2016 American Chemical Society
Improved distribution and reduced toxicity of adriamycin bound to albumin-heparin microspheres
Adriamycin (ADR) was formulated in albumin-heparin conjugate microspheres (AHCMS) to improve site-specific delivery and to reduce the toxicity of the drug. The effect of formulating ADR in AHCMS was investigated upon intrahepatic administration to male Wag/Rij rats. After intraveno-portal (i.v.p.) administration of ADR-AHCMS, ADR peak plasma concentrations were reduced 10-fold and ADR tissue levels of non-target tissues were significantly reduced, as compared to i.v.p. administration of the free drug. At an i.v.p. administered drug dose of 7.5 mg/kg, free ADR showed distinct signs of acute toxicity. At the same dose of ADR-AHCMS, signs of toxicity were absent. Cardiac function parameters which were determined using an isolated working heart model did not change as a result of i.v.p. administration of free ADR or ADR-AHCMS at a dose of 7.5 mg/kg. Heart weights of animals in the ADR-AHCMS or the free ADR groups, however, were significantly lower than controls. Dose tolerance studies after intrahepatic-arterial (i.h.a.) administration of free ADR, empty AHCMS and ADR-AHCMS in rats demonstrated that empty AHCMS are tolerated at a dose of 45 mg/kg. Free ADR was tolerated at a dose of 4 mg/kg, whereas ADR-AHCMS were tolerated up to a dose of 10 mg ADR/kg, as indicated by the survival
Insight into the Effect of Water on the Methanol-to-Olefins Conversion in H-SAPO-34 from Molecular Simulations and in Situ Microspectroscopy
The role of water in the methanol-to-olefins (MTO) process over H-SAPO-34 has been elucidated by a combined theoretical and experimental approach, encompassing advanced molecular dynamics simulations and in situ microspectroscopy. First-principles calculations at the molecular level point out that water competes with methanol and propene for direct access to the Bronsted acid sites. This results in less efficient activation of these molecules, which are crucial for the formation of the hydrocarbon pool. Furthermore, lower intrinsic methanol reactivity toward methoxide formation has been observed. These observations are in line with a longer induction period observed from in situ UV-vis microspectroscopy experiments. These experiments revealed a slower and more homogeneous discoloration of H-SAPO-34, while in situ confocal fluorescence microscopy confirmed the more homogeneous distribution and larger amount of MTO intermediates when cofeeding water. As such, it is shown that water induces a more efficient use of the H-SAPO-34 catalyst crystals at the microscopic level. The combined experimental-theoretical approach gives a profound insight into the role of water in the catalytic process at the molecular and single-particle level. © 2016 American Chemical Society
(99m)Tc-HDP bone scintigraphy and (18)F-sodiumfluoride PET/CT in primary staging of patients with prostate cancer
INTRODUCTION/AIM: Correct staging of patients with prostate cancer is important for treatment planning and prognosis. Although bone scintigraphy with (99m)Tc-phosphonates (BS) is generally advised for staging by guidelines in high risk prostate cancer, this imaging technique is hampered by a high rate of inconclusive results and moderate accuracy. Potentially better imaging techniques for detection of bone metastases such as (18)F-sodiumfluoride PET/CT (NaF PET/CT) are therefore being evaluated. In this observational cohort study we evaluate the performance and clinical impact of both BS and NaF PET/CT in primary staging of patients with prostate cancer. METHODS: The first of two cohorts consisted of patients who received a BS while the second included patients who received a NaF PET/CT for primary staging of prostate cancer. For both cohorts the number of positive, negative and equivocal findings, calculated diagnostic performance of the imaging modality in terms of sensitivity and specificity, as well as the impact on clinical management were studied. The ranges of the diagnostic performance were calculated both assuming that equivocal findings were positive and assuming that they were negative for bone metastases. For the NaF PET/CT cohort the number of patients with signs of lymph node metastases on low dose CT were also recorded, including the impact of these findings on clinical management. RESULTS: One-hundred-and-four patients underwent NaF PET/CT, whereas 122 patients underwent BS. Sensitivities of 97-100 and 84-95% and specificities of 98-100 and 72-100% were found on a patient basis for detection of bone metastases with NaF PET/CT and BS, respectively. Equivocal findings warranted further diagnostic procedures in 2% of the patients in the NaF cohort and in 16% in the BS cohort. In addition NaF PET/CT demonstrated lymph node metastases in 50% of the included patients, of which 25% showed evidence of lymph node metastases only. CONCLUSION: Our data indicate better diagnostic performance of NaF PET/CT compared to BS for detection of bone metastases in primary staging of prostate cancer patients. Less equivocal findings are encountered with NaF PET/CT. Moreover, NaF PET/CT has additional value over BS since lymph node metastases are encountered frequently