First imaging results of an intraindividual comparison of 11C-acetate and 18F-fluorocholine PET/CT in patients with prostate cancer at early biochemical first or second relapse after prostatectomy or radiotherapy

Purpose

¹⁸F-Fluorocholine (FCH) and ¹¹C-acetate (ACE) PET are widely used for detection of recurrent prostate cancer (PC). We present the first results of a comparative, prospective PET/CT study of both tracers evaluated in the same patients presenting with recurrence and low PSA to compare the diagnostic information provided by the two tracers.

Methods

The study group comprised 23 patients studied for a rising PSA level after radical prostatectomy (RP, 7 patients, PSA ≤3 ng/ml), curative radiotherapy (RT, 7 patients, PSA ≤5 ng/ml) or RP and salvage RT (9 patients, PSA ≤5 ng/ml). Both FCH and ACE PET/CT scans were performed in a random sequence a median of 4 days (range 0 to 11 days) apart. FCH PET/CT was started at injection (307?±?16 MBq) with a 10-min dynamic acquisition of the prostate bed, followed by a whole-body PET scan and late (45 min) imaging of the pelvis. ACE PET/CT was performed as a double whole-body PET scan starting 5 and 22 min after injection (994?±?72 MBq), and a late view (45 min) of the prostate bed. PET/CT scans were blindly reviewed by two independent pairs of two experienced nuclear medicine physicians, discordant subgroup results being discussed to reach a consensus for positive, negative end equivocal results.

Results

PET results were concordant in 88 out of 92 local, regional and distant findings (Cohen’s kappa 0.929). In particular, results were concordant in all patients concerning local status, bone metastases and distant findings. Lymph-node results were concordant in 19 patients and different in 4 patients. On a per-patient basis results were concordant in 22 of 23 patients (14 positive, 5 negative and 3 equivocal). In only one patient was ACE PET/CT positive for nodal metastases while FCH PET/CT was overall negative; interestingly, the ACE-positive and FCH-negative lymph nodes became positive in a second FCH PET/CT scan performed a few months later.

Conclusion

Overall, ACE and FCH PET/CT showed excellent concordance, on both a per-lesion and a per-patient basis, suggesting that both tracers perform equally for recurrent prostate cancer staging.     

Analysis of referral patterns,predictive accuracy,and impact on patient management of myocardial perfusion imaging in a new nuclear cardiology laboratory

BACKGROUND: Most of the published data on myocardial perfusion imaging (MPI) come from large tertiary-referral medical centers with extensive experience in cardiac imaging as well as a large volume of procedures. Whether the results of MPI remain as reliable in new nuclear cardiology laboratories with smaller volumes of procedures is unknown. The purpose of this study was to analyze the referral patterns, predictive accuracy, and impact of MPI on clinical practice in a newly opened nuclear cardiology laboratory. METHODS AND RESULTS: We performed a prospective study on all patients referred for MPI at our nuclear cardiology laboratory during its first year of operation. Patients were followed up for 3 months after the MPI study to determine whether they underwent coronary angiography. The study population consisted of 334 patients. Their mean age was 56 +/- 10 years, and 80% were men. Of the patients, 30% were asymptomatic, 29% had angina, and only 6% had recent acute myocardial infarction or unstable angina. Fifty-one patients (fifteen percent) were subsequently referred for coronary angiography. The positive and negative predictive values of MPI were 91% and 86%, respectively. The presence of reversible perfusion defects (P =.02) and the presence of multiple perfusion defects (P =.01) on MPI were the most important determinants of subsequent referral to coronary angiography. CONCLUSIONS: MPI stress testing retains its high diagnostic accuracy in a new nuclear cardiology laboratory with a relatively small volume of procedures. Furthermore, MPI findings in this population had a strong impact on the clinical practice of the referring physicians in terms of subsequent referral to coronary angiography.     

Incretin Response to a Standard Test Meal in a Rat Model of Sleeve Gastrectomy with Diet-Induced Obesity

Background

Currently, the most effective treatment for obesity is bariatric surgery. Gastroduodenal bypass surgery produces sustained weight loss and improves glycemic control and insulin sensitivity. Previous studies have shown that sleeve gastrectomy (SG) produces similar results and implicate changes in incretin hormone release in these effects.

Methods

Male Sprague–Dawley rats were divided into four groups; lean control (lean), diet-induced obesity (DIO), DIO animals that had undergone SG (SG), and DIO animals that had undergone a sham operation (sham).

Results

After a 2-week recovery period, the incretin response to a standard test meal was measured. Blood sampling was performed in free-moving rats at various time points using chronic vascular access to the right jugular vein. There was a significant increase in the bodyweight of DIO animals fed a high-fat/high-sugar diet compared with the lean animals, which was reversed by SG. DIO caused an impairment of the GLP-1 response to a standard test meal, but not the GIP response. SG resulted in a dramatic increase in the GLP-1 response to a standard test meal but had no effect on the GIP response.

Conclusions

A rapid rise in blood sugar was observed in the SG group following a standard test meal that was followed by reactive hypoglycemia. SG dramatically increases the GLP-1 response to a standard test meal but has no effect on GIP in a rat model of DIO.     

Impact of Calcium and Two Doses of Vitamin D on Bone Metabolism in the Elderly: A Randomized Controlled Trial

The optimal dose of vitamin D to optimize bone metabolism in the elderly is unclear. We tested the hypothesis that vitamin D, at a dose higher than recommended by the Institute of Medicine (IOM), has a beneficial effect on bone remodeling and mass. In this double‐blind trial we randomized 257 overweight elderly subjects to receive 1000 mg of elemental calcium citrate/day, and the daily equivalent of 3750 IU/day or 600 IU/day of vitamin D3 for 1 year. The subjects’ mean age was 71 ± 4 years, body mass index 30 ± 4 kg/m², 55% were women, and 222 completed the 12‐month follow‐up. Mean serum 25 hydroxyvitamin D (25OHD) was 20 ng/mL, and rose to 26 ng/mL in the low‐dose arm, and 36 ng/mL in the high‐dose arm, at 1 year (p < 0.05). Plasma parathyroid hormone, osteocalcin, and C‐terminal telopeptide (Cross Laps) levels decreased significantly by 20% to 22% in both arms, but there were no differences between the two groups for any variable, at 6 or 12 months, with the exception of serum calcitriol, which was higher in the high‐dose group at 12 months. Bone mineral density (BMD) increased significantly at the total hip and lumbar spine, but not the femoral neck, in both study arms, whereas subtotal body BMD increased in the high‐dose group only, at 1 year. However, there were no significant differences in percent change BMD between the two study arms at any skeletal site. Subjects with serum 25OHD <20 ng/mL and PTH level >76 pg/mL showed a trend for higher BMD increments at all skeletal sites, in the high‐dose group, that reached significance at the hip. Adverse events were comparable in the two study arms. This controlled trial shows little additional benefit in vitamin D supplementation at a dose exceeding the IOM recommendation of 600 IU/day on BMD and bone markers, in overweight elderly individuals. © 2017 American Society for Bone and Mineral Research.     

Double jeopardy: assessing the association between internal displacement,housing quality and chronic illness in a low-income neighborhood

Purpose  

This study analyzed associations between war-related internal displacement, housing quality and the prevalence of chronic illness in Nabaa, a low-income neighborhood on the outskirts of Beirut, Lebanon.     

Treatment complications among long-term survivors of cervical cancer: treated by surgery or radiotherapy

This study assesses the morbidity and complications of treatment among long-term survivors of cervical cancer. Ninety-eight female patients who were diagnosed and treated from invasive carcinoma of the cervix uteri 5 years or more are included in this study. All the cases were free of disease and had survived up to December 2010. Forty-one cases were treated with radical hysterectomy with removal of the lymph nodes (Wertheim’s surgery) (42%). Radical radiation therapy was given to 57 cases (58%) according to our treatment protocol; weekly cisplatin was given concomitantly with radiation. Although urinary adverse effects were more prevalent among the radiation group, the difference was not statistically significant. Bowel dysfunction was more prevalent and statistically significant (p < 0.001) among the radiotherapy arm. Dysfunctions recorded included change in bowel habit, diarrhea, constipation, tenesmus, soiling of clothes and or flatulence. However, their severity was grade 1–2 only. The frequency of small intestinal obstruction was comparable in both arms. Pelvic vein thromboses had a tendency to occur among the surgical group especially in obese females (p value 0.005). The frequency of sexual dysfunction was comparable in both groups with no statistical difference. It was age related. The younger the patients’ ages, the more was the sexual complaint irrespective to the treatment modality. Sexual problems included dyspareunia from vaginal stenosis shortening or dryness, vulval soreness from itching and dryness. Bearing in mind that many patients had more than one health complaint. The remaining cases denied the presence of any complications and stated that they had a normal life style.     

The prevalence of deliberate self-harm and its relationships to trauma and dissociation among Iranian young adults

This study aims to investigate the prevalence of deliberate self-harm and its relationships to childhood and recent trauma and different patterns of dissociative features. A total of 100 male and 100 female college students were administered a 58-item questionnaire designed to detect the extent of dissociation, deliberate self-harm, and trauma history. Participants with deliberate self-harm behaviors reported more traumatic experiences and dissociative features than participants without such behaviors. Furthermore, the prevalence of deliberate self-harm (i.e., 40.5%) was similar to previous studies on college student populations. However, and contrary to earlier research, deliberate self-harm was significantly more prevalent among men (48%) than women (33%). The findings support the notion that trauma, pathological dissociation, and depersonalization/derealization play important functional roles in self-harm behaviors. From this perspective, it is feasible to understand individuals who engage in self-harm as either escaping from uncomfortable dissociative states or experiencing an infra-psychological conflict in which one dissociative part of the self is being abusive toward another.     

Mechanisms underlying the limited injectability of hydraulic calcium phosphate paste. Part ІІ: Particle separation study

Calcium phosphate cements (CPCs) are of great interest for bone augmentation procedures. In these a hydraulic calcium phosphate paste is injected through a small bore needle into the bone. The injectability of these pastes is relatively poor, resulting into partial injection only. In earlier studies we have shown that phase separation brings the injection process to a halt. Phase separation is characterized by a faster flow of the liquid than of the solid during paste extrusion. So far it is unclear whether or not particle separation contributes to the poor injectability of such hydraulic pastes. It is hypothesized that fine particles behave like a liquid and thus separate under the injection pressure, leaving larger particles behind. A factorial experimental design was used to examine this hypothesis. The particle size distribution (PSD) of the extrudate was measured over the course of each injection experiment using laser diffraction. The solid content of the paste was further inspected using scanning electron microscopy. A total of 48 experiments covering four factors at two levels each were performed. One factor was the ultrasound exposure duration, to ensure the dispersion quality of the particles during the PSD measurements. Another factor was the location of the samples over the course of the injection, so as to compare the extrudate with the PSDs remaining in the syringe. The liquid:powder ratio (LPR) in the injected paste was another factor investigated. Specifically, two different pastes with 40% and 50% LPR were examined. The dispersal medium was a fourth factor investigated, to ensure adequate dispersion of the particles during the PSD measurements. Analysis of variance showed that sample location did not significantly affect PSD. No apparent PSD change for the extruded paste and the paste remaining in the syringe could be detected by scanning electron microscopy. In conclusion, the present study did not show any evidence suggesting that particle separation occurred over the course of injection and thus that phase separation remains the main phenomenon leading to the poor injectability of CPCs.