Background
The rapidly expanding clinical adaptation of prostate-specific membrane antigen (PSMA)-targeted PET imaging in the evaluation of patients with prostate cancer has placed an increasing onus ...on understanding both the potential pearls of interpretation as well as limitations of this new technique. As with any new molecular imaging modality, accurate characterization of abnormalities on PSMA-targeted PET imaging can be accomplished only if one is aware of the normal distribution pattern, physiological variants of radiotracer uptake, and potential sources of false-positive and false-negative imaging findings. In recent years, a growing number of reports have come to light describing incidental non-prostatic benign or malignant pathologies with high uptake on PSMA-targeted PET imaging. In this review, we have summarized the published literature regarding the potential pearls and technical and interpretive pitfalls of this imaging modality. Knowledge of these limitations can increase the confidence of interpreting physicians and thus improve patient care.
Conclusions
As PSMA-targeted PET is expected to be evaluated in larger prospective trials, the dissemination of potential diagnostic pitfalls and the biologic underpinning of those findings will be of increased importance.
The purpose of this article is to summarize the evidence regarding the role of FDG PET/CT in treatment response assessment and surveillance of lung cancer and to provide suggested best practices.
FDG ...PET/CT is a valuable imaging tool for assessing treatment response for patients with lung cancer, though evidence for its comparative effectiveness with chest CT is still evolving. FDG PET/CT is most useful when there is clinical suspicion or other evidence for disease recurrence or metastases. The sequencing, cost analysis, and comparative effectiveness of FDG PET/CT and conventional imaging modalities in the follow-up setting need to be investigated.
Purpose
This meta-analysis aims to establish the diagnostic performance of
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F-NaF-PET/CT for the detection of bone metastases in prostate cancer patients. The performance of
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F-NaF-PET/CT was ...compared with other imaging techniques in the same cohort of patients.
Methods
A systematic search was performed in PubMed/Medline and EMBASE (last Updated, September 28, 2018). Studies with histopathology confirmation and/or clinical/imaging follow-up as reference standard were eligible for inclusion.
Results
A total of 14 studies were included. Twelve studies including 507 patients provided per-patient basis information. The pooled sensitivity, specificity, diagnostic odds ratio (DOR) and the area under the summary receiver operating characteristics curve (AUC) of
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F-NaF-PET/CT for the detection of bone metastases were 0.98 (95% CI 0.95–0.99), 0.90 (95% CI 0.86–0.93), 123.2 and 0.97, respectively. Seven studies provided the lesion-based accuracy information of 1812 lesions identified on
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F-NaF-PET/CT with the pooled sensitivity, specificity, DOR and AUC of 0.97 (95% CI 0.95–0.98), 0.84 (95% CI 0.81–0.87), 206.8 and 0.97, respectively. The overall diagnostic performance of
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F-NaF-PET/CT is superior to
99m
Tc-bone scintigraphy (AUC 0.842;
P
< 0.001; four studies) and
99m
Tc-SPECT (AUC 0.896;
P
< 0.001, four studies). Compared to
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F NaF-PET/CT, whole-body MRI with diffusion-weighted imaging (DWI) was shown to have lower sensitivity (0.83, 95% CI 0.68–0.93), with no significant difference in the overall performance (AUC 0.947;
P
= 0.18, four studies).
Conclusion
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F-NaF-PET/CT has excellent diagnostic performance in the detection of bone metastases in staging and restaging of high-risk prostate cancer patients. The performance of
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F-NaF-PET/CT is superior to
99m
Tc bone scintigraphy and SPECT, and comparable to DWI–MRI.
IQ·SPECT is a recently introduced collimator design for myocardial perfusion imaging (MPI). Little data exist on use of this collimator type in obese patients, particularly Class 2 or 3 body mass ...index (BMI) > 35 kg/m2.
Two consecutive rest–stress MPI scans were prospectively acquired using a conventional collimator and IQ·SPECT (acquisition times of 20 and 7 minutes, respectively) in 20 patients with a BMI of >30 kg/m2. Assigned by two blinded, independent readers, image quality (on a 5-point scale) and metrics of myocardial perfusion summed stress score (SSS), summed rest score (SRS) and summed difference score (SDS) were compared. Software-based left ventricular ejection fraction (EF) was also correlated.
Mean BMI was 39.6 ± 7.6 kg/m2. Class 2 or 3 obesity was present in 12 patients (BMI, 44.1 ± 6.8 kg/m2). Gated/non-gated images from IQ·SPECT revealed fair to good quality scores (median ≥ 3.25), which were inferior to the conventional collimator (median ≥ 4.0; P ≤ 0.01). Significant correlative indices were achieved when comparing IQ·SPECT and conventional collimators for EF values (r = 0.86, P < 0.01), SSS (r = 0.75, P < 0.0001) and SRS (r = 0.60, P < 0.005), but not for SDS (r = 0.15).
IQ·SPECT was comparable to conventional SPECT in obese patients. The reduced acquisition time of IQ·SPECT may allow for improved throughput with no loss in diagnostic accuracy.
Background A growing body of evidence suggests an association between lower serum 25-hydroxy vitamin D (25(OH)VitD) levels and adverse cardiovascular events. Patients with type 2 diabetes mellitus ...(T2DM) are at increased risk for developing coronary heart disease (CHD). 25-Hydroxy vitamin D deficiency is highly prevalent, especially among patients with T2DM. This study aimed to evaluate the predictive value of serum 25(OH)VitD in improvement of CHD risk stratification in patients with T2DM. Methods In an open cohort, community-dwelling T2DM patients were followed up for first CHD event. Patients were divided into 4 categories, based on 25(OH)VitD quartiles. Cox regression analysis was used to obtain hazard ratios. Results A total number of 2,607 T2DM patients were followed up for median time of 8.5 years. During follow-up, 299 patients experienced CHD events. Patients in the lowest quartile experienced more CHD events. Adjusted hazard ratios (95% CI) for developing CHD events were 0.77 (0.55-1.07) for second quartile, 0.52 (0.38-0.73) for third quartile, and 0.43 (0.31-0.60) for fourth quartile, compared with the first quartile. The incidence rate decreased as serum 25(OH)VitD increased, which remained significant after stepwise adjustments ( P value for trend ≤.001). Addition of 25(OH)VitD to traditional risk factors in Framingham Risk Score successfully reclassified 29% of study population. Conclusions Serum 25(OH)VitD is an independent predictor of future adverse CHD events in patients with T2DM. Addition of 25(OH)VitD status to Framingham Risk Score improves CHD risk prediction in patients with T2DM.
Both prostate-specific membrane antigen (PSMA)- and somatostatin receptor (SSTR)-targeted positron emission tomography (PET)-based imaging agents for prostate carcinoma and neuroendocrine tumors, ...respectively, are seeing rapidly expanding use. In addition to diagnostic applications, both classes of radiotracers can be used to triage patients for theranostic endoradiotherapy. While interpreting PSMA- or SSTR-targeted PET/computed tomography (CT) scans, the reader has to be aware of certain pitfalls. Adding to the complexity of the interpretation of those imaging agents, both normal biodistribution, and also false-positive and -negative findings differ between PSMA- and SSTR-targeted PET radiotracers. Herein summarized under the umbrella term molecular imaging reporting and data systems (MI-RADS), two novel RADS classifications for PSMA- and SSTR-targeted PET imaging are described (PSMA- and SSTR-RADS). Notably, PSMA- and SSTR-RADS are structured in a reciprocal fashion, i.e., if the reader is familiar with one system, the other system can readily be applied, as well. In the present review, we will discuss the most common pitfalls on PSMA- and SSTR-targeted PET/CT, briefly introduce PSMA- and SSTR-RADS, and define a potential future role of the umbrella framework MI-RADS compared to other classification systems.
Objective
The aims of this study were to investigate the utility of
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FF-Florastamin, a novel prostate-specific membrane antigen (PSMA)-targeted PET radiotracer with facile radiochemistry, relative ...to the conventional imaging for the detection of sties of disease and evaluate the effect of multi-timepoint imaging with
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FF-Florastamin PET on lesion detectability.
Methods
Eight prostate cancer patients with known or suspected recurrence who underwent
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FF-Florastamin PET/CT at 1-h and 2-h imaging time-points were included in this prospective pilot study.
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FF-Florastamin PET images were interpreted visually and quantitatively at both time points and compared with CIM.
Results
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FF-Florastamin PET was superior to CT in the detection of active osseous metastases and small-sized metastatic lymph nodes that do not fall under the anatomic imaging size criteria for metastasis. Multi-timepoint imaging showed a significant reduction in the blood pool, bone marrow and muscular uptake, and increase in liver uptake over time. There is a significant improvement in tumor-to-background ratio (TBR) at the 2-h imaging time-point (
P
= 0.04). The mean percentage change in TBR at 2-h was 21% (SD = 0.31).
Conclusions
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FF-Florastamin is a promising new radioligand for PSMA-targeted PET with suitable lesion detectability and high TBR at both time points.
Abstract Background The association between homocysteine (Hcy) and metabolic syndrome (MetS)-related disorders remains to be unveiled. First, the role of Hcy–MetS interaction in prediction of ...coronary heart disease (CHD) was assessed. Next, we investigated whether serum Hcy improves CHD risk-prediction beyond MetS and traditional risk factors (TRFs). Design A prospective study of 5893 community-dwelling participants (two sub-cohorts, 3286 diabetic and 2607 non-diabetic; ∼8.5 years of follow-up). Methods Clustering of Hcy with MetS components was assessed using exploratory factor-analysis. Cox regression hazard ratio (HR) was used to predict CHD using Hcy level and MetS status. Baseline model included MetS and TRFs. Addition of Hcy and hyper-homocysteinemia (HHcy) to the baseline model was evaluated in two separate models. Results Hcy was correlated with MetS components, especially with systolic blood pressure. The factor linking MetS to CHD is the factor through which Hcy is linked to MetS. HHcy and MetS interacted as risk factors for CHD. Conclusion Hcy adds to the value of MetS and TRFs for CHD risk-prediction by reclassifying around 47.3–49.0% of the overall and 21.6–28.1% of the intermediate-risk population.
18FDCFPyL is increasingly used for prostate-specific membrane antigen (PSMA) mediated imaging of men with biochemically recurrent prostate cancer (BRPCa). In this meta-analysis, which is updated with ...the addition of multiple new studies, including the definitive phase III CONDOR trial, we discuss the detection efficiency of 18FDCFPyL in BRPCa patients. PubMed was searched on 29 September 2022. Studies evaluating the diagnostic performance of 18FDCFPyL among patients with BRPCa were included. The overall pooled detection rate with a 95% confidence interval (95% CI) was calculated among all included studies and stratified among patients with PSA ≥ 2 vs. <2 ng/mL and with PSA ≥ 0.5 vs. <0.5 ng/mL. The association of detection efficiency with pooled PSA doubling time from two studies was calculated. Seventeen manuscripts, including 2252 patients, met the inclusion criteria and were used for data extraction. A previous meta-analysis reported that the pooled detection rate was 0.81 (95% CI: 0.77–0.85), while our study showed a pooled overall detection rate of 0.73 (95% CI: 0.66–0.79). An increased proportion of positive scans were found in patients with PSA ≥ 2 vs. <2 ng/mL and PSA ≥ 0.5 vs. <0.5 ng/mL. No significant difference was found in detection efficiency between those with PSA doubling time ≥ 12 vs. <12 months. Detection efficiency is statistically related to serum PSA levels but not to PSA doubling time based on available data. The detection efficiency of 18FDCFPyL in men with BRPCa has trended down since a previous meta-analysis, which may reflect increasingly stringent inclusion criteria for studies over time.
This study investigates whether the addition of preoperative Tc-MIBI SPECT/CT can increase the degree of diagnostic confidence in the differentiation of benign from malignant enhancing renal masses.
...Patients were recruited as part of an institutional review board-approved prospective clinical trial. Forty-eight patients with clinical stage T1 solid renal masses who underwent a Tc-MIBI SPECT/CT before partial or radical nephrectomy were evaluated. Conventional CT and MRI, which were approximately performed within 8 weeks before Tc-MIBI, were retrospectively retrieved. Based on a 5-point scale (1 = definitely benign, 5 = definitely malignant), 2 blinded readers recorded their degree of confidence for each lesion using conventional imaging before and after reviewing the Tc-MIBI uptake ratios. Surgical pathology was considered as the reference standard.
Additional review of Tc-MIBI SPECT/CT uptake ratios increased diagnostic confidence in the differentiation of solid renal masses in 14/48 lesions (29.2%). In 9 lesions, the addition of Tc-MIBI changed the initial confidence levels of malignancy toward benign diagnosis. Postsurgical pathology confirmed the diagnosis of benign histology (oncocytoma/hybrid oncocytic-chromophobe tumors) in 7 and chromophobe renal cell carcinoma (behave as indolent) in 2 of these lesions. Tc-MIBI increased the confidence level toward malignancy in 5 cases; all were confirmed as RCC on surgical pathology. The area under the receiver operative characteristic curve was 0.60 for conventional imaging alone and 0.85 after reviewing Tc-MIBI (P for difference = 0.03).
Preoperative Tc-MIBI SPECT/CT enhances the performance of conventional imaging, improving the characterization of benign histologies and lowering the possibility of misclassification.
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