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Early and precise localization of recurrent prostate cancer lesions after local therapy facilitates optimal disease management. Here, we present results from a single-center study to evaluate the utility of [18F]fluciclovine PET/CT to localize prostate cancer recurrence in patients with PSA 0–

Purpose: F-18-fluciclovine PET is approved for prostate cancer recurrence imaging. According to the radiopharmaceutical package insert only 3% of the tracer is expected to be excreted in the urine over the first four hours. Yet, in clinical practice we noticed a higher percentage of bladder excretion. We sought to evaluate and quantify early fluciclovine bladder radioactivity and determine if refraining from voiding before fluciclovine injection would mitigate it. Materials and Methods: 159 patients underwent fluciclovine PET/CT imaging as part of their clinical workup. The first 36 patients were instructed to void just before fluciclovine injection, the subsequent 123 patients were not requested to void. The SUVmax and SUVmean of the bladder, aorta, marrow, liver, and bladder volumes were collected. Comparing SUVmean of bladder to background, we characterized bladder radioactivity as: "Insignificant" (bladder aorta, marrow, liver). Differences between the protocols were investigated. Results: Overall, 22% (35/159) of patients had moderate, and 8.8% (14/159) had intense bladder activity. A negative association was found between bladder volumes and SUVmean. A significant difference was found between voiding and non-voiding protocol groups, with 38.9% (14/36) vs. 17.1% (21/123) of patients having moderate, and 22.2% (8/36) vs. 4.9% (6/123) of patients having intense bladder activity, respectively. Conclusion: Refraining from voiding prior to F-18-fluciclovine injection results in significantly lower urinary bladder radioactivity compared to purposeful voiding pre-injection. We have modified our practice accordingly, particularly as moderate and intense bladder activity may mask/mimic local prostate cancer recurrence. Mechanisms underlying this phenomenon should be further investigated.

*Maurer AH, Burshteyn M, Adler LP, Steiner RM. How to differentiate benign versus malignant cardiac and paracardiac 18F FDG uptake at oncologic PET/CT. RadioGraphics. 2011;31:1287–1305.

Chronic constipation and gastrointestinal motility disorders constitute a large part of a gastroenterology practice and have a significant impact on a patient's quality of life and lifestyle. In most cases, medications are prescribed to alleviate symptoms without there being an objective measurement of response. Commonly used investigations of gastrointestinal transit times are currently limited to radiopaque markers or electronic capsules. Repeated use of these techniques is limited because of the radiation exposure and the significant cost of the devices. We present the proof of concept for a new device to measure gastrointestinal transit time using commonly available and inexpensive materials with only a small amount of radiotracer. Methods: We assembled gelatin capsules containing a 67Ga-citrate-radiolabeled grain of rice embedded in paraffin for use as a point-source transit device. It was tested for stability in vitro and subsequently was given orally to 4 healthy volunteers and 10 patients with constipation or diarrhea. Imaging was performed at regular intervals until the device was excreted. Results: The device remained intact and visible as a point source in all subjects until excretion. When used along with a diary of bowel movement times and dates, the device could determine the total transit time. The device could be visualized either alone or in combination with a barium small-bowel follow-through study or a gastric emptying study. Conclusion: The use of a point-source transit device for the determination of gastrointestinal transit time is a feasible alternative to other methods. The device is inexpensive and easy to assemble, requires only a small amount of radiotracer, and remains inert throughout the gastrointestinal tract, allowing for accurate determination of gastrointestinal transit time. Further investigation of the device is required to establish optimum imaging parameters and reference values. Measurements of gastrointestinal transit time may be useful in managing patients with dysmotility and in selecting the appropriate pharmaceutical treatment.

Prostate cancer recurrence after definitive therapy is not uncommon. Recurrent disease is first detected by the elevation of prostate specific antigen (PSA) and may often be radiographically occult. The use of molecular imaging for the localization and staging of recurrent prostate cancer is promising. 18F-Fluciclovine is a synthetic amino acid analog positron emission tomography (PET) tracer which has demonstrated great utility in the evaluation of patients with suspected recurrence disease. Other newer PET tracers such 68Ga/18F-PSMA-ligands are being investigated for prostate imaging with promising results. The purpose of this article is to review the emerging role of fluciclovine in clinical practice for patients with prostate cancer. Since the approval of fluciclovine by the Food and Drug Administration, the modality is widely used in the USA for patients with suspect disease recurrence. With the coming approval of newer generation of PET tracers, it is important to understand the unique mechanism of action and the diagnostic performance of fluciclovine PET/CT in prostate cancer imaging to allow better allocation of the radiotracers. This review article provides a broad literature review of the current and the future potential role of fluciclovine PET/CT in prostate cancer imaging.

A written directive is required by the U.S. Nuclear Regulatory Commission for any use of 131I above 1.11 MBq (30 μCi) and for patients receiving radiopharmaceutical therapy. This requirement has also been adopted and must be enforced by the agreement states. As the introduction of new radiopharmaceuticals increases therapeutic options in nuclear medicine, time spent on regulatory paperwork also increases. The pressure of managing these time-consuming regulatory requirements may heighten the potential for inaccurate or incomplete directive data and subsequent regulatory violations. To improve on the paper-trail method of directive management, we created a software tool using a Health Insurance Portability and Accountability Act (HIPAA)-compliant database. This software allows for secure data-sharing among physicians, technologists, and managers while saving time, reducing errors, and eliminating the possibility of loss and duplication. Methods: The software tool was developed using Visual Basic, which is part of the Visual Studio development environment for the Windows platform. Patient data are deposited in an Access database on a local HIPAA-compliant secure server or hard disk. Once a working version had been developed, it was installed at our institution and used to manage directives. Updates and modifications of the software were released regularly until no more significant problems were found with its operation. Results: The software has been used at our institution for over 2 y and has reliably kept track of all directives. All physicians and technologists use the software daily and find it superior to paper directives. They can retrieve active directives at any stage of completion, as well as completed directives. Conclusion: We have developed a software solution for the management of written directives that streamlines and structures the departmental workflow. This solution saves time, centralizes the information for all staff to share, and decreases confusion about the creation, completion, filing, and retrieval of directives.