Generating Evidence for Clinical Benefit of PET/CT in Diagnosing Cancer Patients
ABSTRACT For diagnostic methods such as PET/CT, not only diagnostic accuracy but also clinical benefit must be demonstrated. However, there is a lack of consensus about how to approach this task. Here we consider 6 clinical scenarios to review some basic approaches to demonstrating the clinical benefit of PET/CT in cancer patients: replacement of an invasive procedure, improved accuracy of initial diagnosis, improved accuracy of staging for curative versus palliative treatment, improved accuracy of staging for radiation versus chemotherapy, response evaluation, and acceleration of clinical decisions. We also develop some guidelines for the evaluation of clinical benefit. First, it should be clarified whether there is a direct benefit of the use of PET/CT or an indirect benefit because of improved diagnostic accuracy. If there is an indirect benefit, then decision modeling should be used initially to assess the benefit expected from the use of PET/CT. Only if decision modeling does not allow definitive conclusions should randomized controlled trials be planned.
- SourceAvailable from: Ken Herrmann
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- "However, the National Oncologic PET Registry did not address the impact of management changes on patient outcome. The challenges to establish such evidence have been summarized recently [148–150]. "
ABSTRACT: The discovery of the Warburg effect in the early twentieth century followed by the development of the fluorinated glucose analogue 18F-fluorodeoxyglucose (18F-FDG) and the invention of positron emission tomographs laid the foundation of clinical PET/CT. This review discusses the challenges and obstacles in clinical adoption of this technique. We then discuss advances in instrumentation, including the critically important introduction of PET/CT and current PET/CT protocols. Moreover, we provide evidence for the clinical utility of PET/CT for patient management and its potential impact on patient outcome, and address its cost and cost-effectiveness. Although this review largely focuses on 18F-FDG imaging, we also discuss a variety of additional molecular imaging approaches that can be used for cancer phenotyping with PET. Throughout this review we emphasize the critical contributions of CT to the strength of PET/CT.09/2013; 1(3). DOI:10.1007/s40134-013-0016-x
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- "It has been a decade now since tomographic hybrid scanners including SPECT/CT (Single-photon emission computed tomography-computerized tomography) and PET/CT (positron emission tomography-computed tomography) have been introduced into nuclear medicine. These techniques provide a higher diagnostic accuracy than conventional non-tomographic scans (1).There has been a considerable emphasis on the benefits of PET/CT in oncology (2,3,4,5,6,7), but relatively less research proven emphasis on the SPECT/CT (8). Due to high investment expense and ongoing benefit to cost analysis, the clinical utility of SPECT/CT still warrants proof of data expressing its superiority. "
ABSTRACT: Objective: To assess the clinical utility of SPECT/ CT in subjects with endocrine and neuroendocrine tumors compared to SPECT alone. Material and Methods: 48 subjects (31 women;17 men; mean age 54±11) with clinical suspicion or diagnosis of endocrine and neuroendocrine tumor had 50 SPECT/CT scans (32 Tc-99m MIBI, 5 post treatment I-131, 8 In-111 Pentetreotide, and 5 I-123 MIBG). SPECT alone findings were compared to SPECT/CT and to pathology or radiological follow up. Results: From the 32 Tc-99m MIBI scans, SPECT accurately localized the lesion in 22 positive subjects while SPECT/CT did in 31 subjects. Parathyroid lesions not seen on SPECT alone were smaller than 10 mm. In five post treatment I-131 scans, SPECT alone neither characterized, nor localized any lesions accurately. SPECT/CT revealed 3 benign etiologies, a metastatic lymph node, and one equivocal lesion. In 8 In-111 Pentetreotide scans, SPECT alone could not localize primary or metastatic lesions in 6 subjects all of which were localized with SPECT/CT. In five I-123 MIBG scans, SPECT alone could not detect a 1.1 cm adrenal lesion or correctly characterize normal physiologic adrenal uptake in consecutive scans of the same patient with prior history of adrenelectomy, all of which were correctly localized and characterized with SPECT/CT. Conclusion: SPECT/CT is superior to SPECT alone in the assessment of endocrine and neuroendocrine tumors. It is better in lesion localization and lesion characterization leading to a decrease in the number of equivocal findings. SPECT/CT should be included in the clinical work up of all patients with diagnosis or suspicion of endocrine and neuroendocrine tumors. Conflict of interest:None declared.12/2012; 21(3):91-6. DOI:10.4274/Mirt.80299
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- "Combining results from accuracy studies with expected benefit from improved diagnoses  "
ABSTRACT: The purpose of this paper was to contrast interim analyses in (randomized controlled) treatment studies with interim analyses in paired diagnostic studies of accuracy with respect to planning and conduct. The term 'treatment study' refers to a (randomized) clinical trial that aims to demonstrate the superiority or noninferiority of one treatment compared with another, and the term 'diagnostic study' to a clinical study that compares two diagnostic procedures, using a third diagnostic procedure as the gold standard. Though interim analyses in treatment studies and paired diagnostic studies show similarities in a priori planning of timing, decision rules, and the consequences of the analyses, they differ with respect to (1) the need for sample size adjustments, (2) the possibility of early decisions without early stopping, and (3) the impact of keeping results secret. These differences are due, respectively, to certain characteristics of paired diagnostic studies: the dependence of the sample size on the agreement rate between the modalities, multiple aims of diagnostic accuracy studies, and the advantages of early unblinding of results at the individual level. We exemplified our points by using a recent investigation at our institution on the detection of bone metastases from prostate cancer in patients with histologically confirmed prostate cancer in which (99m)Tc-MDP whole body bone scintigraphy was compared to positron emission tomography/computed tomography with (18)F-fluorocholine as tracer, using magnetic resonance imaging as a reference.American Journal of Nuclear Medicine and Molecular Imaging 01/2012; 2(3):344-52. · 3.25 Impact Factor