Diagnostic efficacy of [68Ga]Ga-DOTA-GPFAPI-04 in patients with solid tumors in a head-to-head comparison with [18F]F-FDG: results from a prospective clinical study.

PURPOSE: To identify the biodistribution and diagnostic performance of a novel fibroblast activation protein (FAP) targeted positron emission tomography (PET) tracer, [68Ga]Ga-DOTA-GPFAPI-04, in patients with solid tumors in a head-to-head comparison with [18F]F-FDG. METHODS: Twenty-six patients histologically proven with cancers of nasopharyngeal (n = 5), esophagus (n = 5), gastro-esophagus (n = 1), stomach (n = 7), liver (n = 3), and colorectum (n = 5) were recruited for [68Ga]Ga-DOTA-GPFAPI-04 and [18F]F-FDG PET/CT scans on consecutive days. The primary endpoint was the diagnostic efficacy, with the histological diagnosis and the follow-up results selected as the gold standard. The secondary endpoint was the background uptake pattern. Two experienced nuclear medicine physicians who were blinded to the gold standard results while having essential awareness of the clinical context reviewed the images and labeled lesions by consensus for subsequent software-assisted lesion segmentation. Additionally, background organs were automatically segmented, assisted by artificial intelligence. Volume, mean, and maximum standard uptake values (SUVmean and SUVmax) of all segmentations were recorded. P < 0.05 was deemed as statistically significant. RESULTS: Significant glandular uptake of [68Ga]Ga-DOTA-GPFAPI-04 was detected in the thyroid, pancreas, and submandibular glands, while moderate uptake was observed in the parotid glands. The myocardium and myometrium exhibited 2-3 times higher uptake of the radiotracer than that of the background levels in blood and liver. A total of 349 targeted lesions, consisting of 324 malignancies and 25 benign lesions, were segmented. [68Ga]Ga-DOTA-GPFAPI-04 is more sensitive than [18F]F-FDG, especially for abdominopelvic dissemination (1.000 vs. 0.475, P < 0.001). Interestingly, [18F]F-FDG demonstrated higher sensitivity for lung metastasis compared to [68Ga]Ga-DOTA-GPFAPI-04 (0.845 vs. 0.682, P = 0.003). The high glandular uptake made it difficult to delineate lesions in close proximity and masked two metastatic lesions in these organs. CONCLUSION: Despite prominent glandular uptake, [68Ga]Ga-DOTA-GPFAPI-04 demonstrates favorable diagnostic performance. It is a promising probe scaffold for further development of FAP-targeted tumor theranostic agents.

Multiparametric cardiovascular magnetic resonance characteristics and dynamic changes in asymptomatic heart-transplanted patients.

OBJECTIVES: To describe the dynamic changes in cardiac deformation and tissue characteristics using cardiac magnetic resonance (CMR) in asymptomatic patients during 12 months after heart transplantation (HT). METHODS: From April 2020 to January 2021, 21 consecutive HT patients without clinical symptoms were included in this prospective study. Multiparametric CMR was performed at 3, 6, and 12 months after HT. Twenty-five healthy volunteers served as controls. RESULTS: During follow-up, a decline in left ventricular (LV) global radial strain (GRS) (p = 0.020) and right ventricular (RV) global longitudinal strain (GLS) (p < 0.001) and an increase in post-contrast T1 (p = 0.024) and T2 (p < 0.001) in asymptomatic HT patients occurred at 3 months, which normalized at 6 months postoperatively, compared with those in healthy controls. A decline in LVGLS (p < 0.001) and LV global circumferential strain (GCS) (p < 0.001) and an increase in native T1 (p < 0.001), T2 (p < 0.001), and extracellular volume (ECV) (p < 0.001) occurred at 3 months. Although most parameters improved gradually, LVGLS, native T1, and ECV remained abnormal compared with those in healthy controls at 12 months; only T2 and LVGCS were normalized at 6 months and 12 months, respectively. ECV was significantly correlated with LVGLS, LVGCS, and LVGRS. CONCLUSION: Cardiac deformation and tissue characteristics were abnormal early after HT, although the patients were clinically asymptomatic. The dynamic changes in CMR characteristics demonstrate a gradual recovery of myocardial injury associated with transplantation during the first 12 months after HT. KEY POINTS: • Multiparametric CMR can detect the dynamic changes of transplantation-associated myocardial injury. • Post-contrast T1, T2, LVGRS, and RVGLS values are normalized at 6 months after HT. • Native T1, ECV, and LVGLS values remain abnormal compared with those in healthy controls at 12 months after HT.

Ringlike late gadolinium enhancement provides incremental prognostic value in non-classical arrhythmogenic cardiomyopathy.

BACKGROUND: The 2019 arrhythmogenic right ventricular cardiomyopathy (ARVC) risk model has proved insufficient in the capability of predicting ventricular arrhythmia (VA) risk in non-classical arrhythmogenic cardiomyopathy (ACM). Furthermore, the prognostic value of ringlike late gadolinium enhancement (LGE) of the left ventricle in non-classical ACM remains unknown. We aimed to assess the incremental value of ringlike LGE over the 2019 ARVC risk model in predicting sustained VA in patients with non-classical ACM. METHODS: In this retrospective study, consecutive patients with non-classical ACM who underwent CMR from January 2011 to January 2022 were included. The pattern of LGE was categorized as no, non-ringlike, and ringlike LGE. The primary outcome was defined as the occurrence of sustained VA. Univariable and multivariable Cox regression analysis was used to evaluate the impact of LGE patterns on sustained VA and area under curve (AUC) was calculated for the incremental value of ringlike LGE. RESULTS: A total of 73 patients were collected in the final cohort (mean age, 39.3 ± 14.4 years, 51 male), of whom 10 (13.7%) had no LGE, 33 (45.2%) had non-ringlike LGE, and 30 (41.1%) had ringlike LGE. There was no statistically significant difference in the 5-year risk score among the three groups (P = 0.190). During a median follow-up of 34 (13-56) months, 34 (46.6%) patients experienced sustained VA, including 1 (10.0%), 13 (39.4%) and 20 (66.7%) of patients with no, non-ringlike and ringlike LGE, respectively. After multivariable adjustment, ringlike LGE remained independently associated with the presence of sustained VA (adjusted hazard ratio: 6.91, 95% confidence intervals: 1.89-54.60; P = 0.036). Adding ringlike LGE to the 2019 ARVC risk model showed significantly incremental prognostic value for sustained VA (AUC: 0.80 vs. 0.67; P = 0.024). CONCLUSION: Ringlike LGE provides independent and incremental prognostic value over the 2019 ARVC risk model in patients with non-classical ACM.

Diagnostic challenges in primary cardiac lymphoma, the opportunity of 18F-FDG PET/CT integrated with contrast-enhanced CT.

BACKGROUND: The purpose of this study was to retrospectively evaluate the value of 18F-FDG PET/CT integrated with contrast-enhanced CT (CECT) in the differential diagnosis of primary cardiac lymphomas (PCLs) and primary cardiac angiosarcomas (PCAs). METHODS: Clinical and imaging data of patients with PCLs and PCAs were collected. All patients underwent preoperative 18F-FDG PET/CT and thoracic CECT. The enhancement pattern and tumor morphology were analyzed using CECT images. The intensity- and volume-based PET parameters of cardiac lesions were analyzed. The performance characteristics of all parameters were assessed. RESULTS: Nine patients with PCL and eight patients with PCA were analyzed. There were significant differences in SUVmax (t = 3.790, P = .002), SUVmean (t = 4.273, P = .001), metabolic tumor volume (U = 13.00, P = .027), tumor-to-liver ratio (U = 10.00, P = .011), and total lesion glycolysis (U = 4.0, P = .001) between PCLs and PC18As. There were significant differences in the enhancement pattern of tumors (P = .002) and tumor morphology (P = .015). The combination of F-FDG PET/CT and CECT improved the diagnostic accuracy, and the combination cutoff (SUVmean > 5.17) could reach 100%, but the difference was not statistically significant (P > .05). CONCLUSION: The intensity- and volume-based PET parameters of PCL were significantly higher than those of PCA. The enhancement pattern and tumor morphology were also different. According to these characteristics, the two most common types of primary cardiac malignancies can be differentiated.

MicroRNA-33b regulates hepatocellular carcinoma cell proliferation, apoptosis, and mobility via targeting Fli-1-mediated Notch1 pathway.

MicroRNAs (miRNAs) have been confirmed to play pivotal roles in hepatocellular carcinoma (HCC) carcinogenesis. However, the underlying function of microRNA-33b (miR-33b) in HCC remains unclear. Here, we found that miR-33b level was significantly reduced in both HCC tissues and tumor cell lines. Further, luciferase reporter assay and western blot analysis confirmed that Friend leukemia virus integration 1 (Fli-1) was a direct target of miR-33b. Overexpression of miR-33b dramatically suppressed HCC tumor cell proliferation and cell mobility, but facilitated tumor cell apoptosis in vitro. Besides, restoration of Fli-1 partially attenuated miR-33b-mediated inhibition of cell growth and metastasis via activating Notch1 signaling and its downstream effectors. Our findings demonstrate the important role of miR-33b/Fli-1 axis in HCC progression and provide novel therapeutic candidates for HCC clinical treatment.

FDG-PET/CT of invasive thymoma extending into the superior vena cava and right atrium.

We present FDG PET/CT findings of a rare case of invasive thymoma with intraluminal growth into the superior vena cava (SVC) and right atrium (RA).

Single-step spatial rotation error separation technique for the ultraprecision measurement of surface profiles.

To improve the measurement accuracy of the profilometer for large optical surfaces, a new single-step spatial rotation error separation technique (SSEST) is proposed to separate the surface profile error and spindle spatial rotation error, and a novel SSEST-based system for surface profile measurement is developed. In the process of separation, two sets of measured results at the ith measurement circle are obtained before and after the rotation of error separation table, the surface profile error and spatial rotation error of spindle can be determined using discrete Fourier-transform and harmonic analysis. Theoretical analyses and experimental results indicate that SSEST can accurately separate spatial rotation error of spindle from the measured surface profile results within the range of 1-100 upr and improve the accuracy of surface profile measurements.

Kinetic modeling and parametric imaging of 18 F-PSMA-11: An evaluation based on total-body dynamic positron emission tomography scans.

BACKGROUND: The prostate-specific membrane antigen (PSMA) targeted positron-emitting tomography (PET) tracers are increasingly used in clinical practice, with novel tracers constantly being developed. Recently, 18 F-PSMA-11 has been gaining growing interest for several merits; however, direct in vivo visualization of its kinetic features in humans remains lacking. PURPOSE: To visualize the kinetic features of 18 F-PSMA-11 in healthy subjects and patients with prostate cancer derived from the total-body dynamic PET scans. METHODS: A total of 8 healthy volunteers (7 males; 1 female) and 3 patients with prostate cancer underwent total-body PET/CT imaging at 1 and 2 h post injection (p.i.) of 18 F-PSMA-11, of which 7 healthy subjects and 3 patients underwent total-body dynamic PET scans lasting 30 min. Reversible two-tissue compartments (2TC) and Patlak models were fitted based on the voxel-based time activity curves (TACs), with the parametric images generated subsequently. Additionally, semi-automated segmentation of multiple organs was performed in the dynamic images to measure the SUVmean at different time points and in the parametric images to estimate the mean value of the kinetic parameters of these organs. RESULTS: 18 F-PSMA-11 showed quick accumulation within prostate cancer, as early as 45 s after tracer injection. It was rapidly cleared from blood circulation and predominantly excreted through the urinary system. High and rapid radiotracer accumulation was observed in the liver, spleen, lacrimal glands, and salivary glands, whereas gradual accumulation was observed in the skeleton. Prostate cancer tissue is visualized in all parametric images, and best seen in DV and Patlak Ki images. Patlak Ki showed a good correlation with 2TC Ki values (r = 0.858, p < 0.05) but less noise than 2TC images. A scanning time point of 30-35 min p.i. was then suggested for satisfactory tumor to background ratio. CONCLUSION: Prostate cancer tissue is visible in most parametric images, and is better shown by Patlak Ki and 2TC DV images. Patlak Ki is consistent with, and thus is preferred over, 2TC Ki images for substantially quicker calculation. Based on the dynamic imaging analysis, a shorter uptake time (30-35 min) might be preferred for a better balance of tumor to background ratio.

A multimodal physiological and psychological dataset for human with mental stress induced myocardial ischemia.

Accurate differentiation between angina with no obstructive coronary arteries (ANOCA) and mental stress-induced myocardial ischemia (MSIMI) is crucial for tailored treatment strategies, yet public data scarcity hampers understanding. Given the higher incidence of both conditions in women, this study prospectively enrolled 80 female ANOCA and 39 age-matched female controls, subjecting them to three types of mental stress tasks. ECGs were continuously monitored across Rest, Stress, and Recover stages of the mental stress tasks, with PET/CT imaging during the Stress stage to evaluate myocardial perfusion. With PET/CT serving as the gold standard for MSIMI diagnosis, 35 of the 80 ANOCA patients were diagnosed as MSIMI. Using ECG variables from different stages of mental stress tasks, we developed five machine learning models to diagnose MSIMI. The results showed that ECG data from different stages provide valuable information for MSIMI classification. Additionally, the dataset encompassed demographic details, physiological, and blood sample test results of the patients. We anticipate this new dataset will significantly push further progress in ANOCA and MSIMI research.

[Effect of needling at waiguan (SJ5) on brain glucose metabolism in patients with cerebral infarction].

OBJECTIVE: To observe changes of brain glucose metabolism by needling at Waiguan (SJ5) in cerebral infraction (CI) patients using 18F-fluorodeoxyglucose (FDG) positron-emission computer tomography (PET/CT), thus exploring its effect and mechanisms. METHODS: A total of 21 patients with CI were recruited in this study. The location of lesion was limited to the left basal ganglia by CT or MRI scan. All patients were randomly assigned to three groups. i.e., the acupoint group (Group A), the non-acupoint group (Group B), the blank control group (Group C), 7 in each group. Patients in Group A were needled at right Waiguan (SJ5). Those in Group B were needled at non-acupoint [10 mm beside Waiguan (SJ5)], whereas those in Group C did not receive any treatment. All patients underwent PET/CT head scan. All data were statistically analyzed using SPSS 13.0 Software and SPM8 Software. RESULTS: Compared with Group C, glucose metabolism increased in bilateral superior temporal gyrus (BA38), right superior frontal gyrus (BA9), left cingulate gyrus (BA24), left culmen and pyramid of cerebellum, and right cerebellar tonsil of cerebellum in Group A. Compared with Group C, glucose metabolism increased in bilateral superior frontal gyrus (BA6, BA9, BA10), bilateral middle frontal gyrus (BA6, BA10), left middle frontal gyrus (BA4), bilateral uncus of limbic lobe (BA36, BA38), left cingulate gyrus (BA24, BA31), left posterior cingulate gyrus (BA30), left precuneus (BA7), left inferior parietal lobule (BA4), and left lingual gyrus of occipital lobe (BA18) in Group B. Compared with Group B, glucose metabolism increased in bilateral superior temporal gyrus (BA22, BA38), right inferior frontal gyrus (BA47), left culmen and cerebellar tonsil of cerebellum in Group A. Activated encephalic regions of needling at Waiguan (SJ5) were mainly dominated in the healthy side, bilateral superior temporal gyrus, and right inferior frontal gyrus. Activated encephalic regions of cerebellum were located at the left cerebellar hemisphere, left culmen of anterior cerebella lobe, and bilateral cerebellar tonsil of posterior cerebella lobe. CONCLUSIONS: Needling at Waiguan (SJ5) of CI patients induced increased glucose metabolism in local cerebral regions. Functional neuroimaging using PET/CT could directly reflect changes of brain glucose metabolism by acupuncture.

Incidental Finding of Intervertebral Disc Herniation With Increased 18F-FAPI-04 Uptake in a Healthy Volunteer.

ABSTRACT: A 44-year-old healthy volunteer received an 18F-FAPI-04 scan for a normal biodistribution and dosimetry study. An incidental finding of an increased uptake of the radiotracer at the L4/5 subarticular disc herniation was noted, and a subsequent MRI scan confirmed the degenerative nature of the lesion.

Increased 18 F-FAPI-04 Uptake in Vertebral Hemangioma.

ABSTRACT: A 54-year-old man with a history of colectomy for colorectal cancer and subsequent liver metastasectomy underwent 18 F-FDG PET/CT and 18 F-FAPI-04 PET/CT scans to evaluate possible hepatic metastasis revealed by contrast-enhanced MRI. Both studies showed similarly increased uptake in liver metastases, and 18 F-FDG detected a metastatic lung nodule. Furthermore, the images showed an incidental finding of increased uptake of 18 F-FAPI-04 in the L3 vertebral, which was not 18 F-FDG-avid. A review of the patient's previous CT and MRI scans suggests vertebral hemangioma.