Value SUVmax Research Articles

Radiology–pathology correlation of hormonal subtypes of breast cancer based on mammography, ultrasound, and PET imaging

BackgroundBreast cancer is one of the most common cancers among the female population globally and a major cause of death due to cancers among women. It has been classified into histopathological, hormonal, and molecular subtypes based on hormone receptor status. Their management involves a multidisciplinary approach depending on these subtypes, TNM staging, tumour size, and site. The purpose of this study was to assess the correlation between ultrasound and mammography characteristics and the maximum standardized uptake value on PET with hormonal subtypes of breast cancer.MethodsIt was a retrospective study from a single-centre data available for 8 months. In this study, 5 hormonal subtypes were considered; Luminal A, Luminal B, Luminal HER2-positive subtype, HER2-enriched subtype, and triple-negative subtype. The morphology of the lesions analysed on mammography and sonography and the SUV max value on PET were considered for analyses. The prediction performance of these features for the hormonal subtypes of breast cancers was then analysed.ResultsLuminal A and B subtypes of breast cancer had indistinct margins with posterior acoustic shadowing on ultrasound. Triple-negative subtypes were well-circumscribed lesions with posterior acoustic enhancement on ultrasound. HER2-positive lesions characteristically had pleomorphic microcalcifications with mixed posterior acoustic features on mammography. On PET, HER2-enriched cases had the highest SUV, and the Luminal A subtype had the lowest SUV.ConclusionAccording to our observations, there are certain typical morphological imaging characteristics for each hormonal subtype of breast cancer. These imaging modalities may help radiologists and clinicians in stratifying their patients for prognostication and better management.

PRIMARY scoring in 68Ga-PSMA PET/CT: correlation with prostate cancer risk groups and its potential impact on active surveillance.

The PRIMARY scoring system is a scale designed to identify clinically significant intraprostatic malignancies on 68Ga-PSMA PET/CT images. Active surveillance is a management method for patients with low-risk prostate cancer. In this study, we aimed to assess the efficacy of PRIMARY scoring in identifying appropriate candidates for active surveillance based on the distribution within prostate cancer risk groups. The data of 134 patients diagnosed with PCa by biopsy who underwent 68Ga-PSMA PET/CT imaging for post-diagnostic staging purposes were retrospectively analyzed. Age, total PSA, ISUP grade, prostate lesion SUVmax values, PI-RADS scores, and PRIMARY scores were recorded. Patients were classified into low-risk and intermediate/high-risk groups. In the intermediate/high-risk group, the PRIMARY score was 1-2 in 17.6% and 3-5 in 82.4% of patients. In the low-risk group, the PRIMARY score was 1-2 in 34.7% and 3-5 in 65.3% of patients. None of the patients in the low-risk group had a PRIMARY score of 5. The most frequent PRIMARY score in both groups was 4, and there was a significant difference between the average SUVmax values of the intermediate/high and low-risk groups with a PRIMARY score of 4 (p = 0.018). The sensitivity of PRIMARY scoring in detecting patients in the intermediate/high-risk group was 82.3%, the specificity was 34.6%, and the positive predictive value (PPV) was 68.6%. When a cut-off SUVmax value 5.0 was used for the PRIMARY score of 4, the sensitivity was 67.0%, the specificity was 65.3% and the PPV was 77.0%. In the ROC analysis, the area under the curve was 0.727 for PRIMARY scoring, 0.662 for PI-RADS, and 0.744 for their combined mean. The PRIMARY scoring system can complement PI-RADS scoring in mpMRI for selecting patients suitable for active surveillance. Revising the PRIMARY score 4 with an SUVmax cut-off value may increase the specificity.

Relationship between [18F]FDG PET/CT findings and claudin 18.2 expression in metastatic gastric cancer.

Given that claudin 18.2 (CLDN18.2) is a cell surface protein specifically expressed by gastric cancer cells, anti-CLDN18.2 antibodies have demonstrated significant antitumor effects in patients with advanced gastric adenocarcinoma. The correlation of [18F]FDG PET/CT with CLDN18.2 expression remains unexplored. This study aimed to investigate whether CLDN18.2 expression was associated with [18F]FDG uptake and whether [18F]FDG PET/CT can be used to predict the CLDN18.2 status of gastric cancer. A retrospective analysis of [18F]FDG PET/CT images from 163 patients diagnosed with metastatic gastric cancer was conducted, and the expression of CLDN18.2 was assessed immunohistochemically. SUVmax, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were calculated in 3D mode using vendor-provided software. The relationship between PET metabolic parameters and CLDN18.2 status was analyzed. CLDN18.2-negative tumors showed a higher median SUVmax of 13.2 (1.8-46.7) compared to CLDN18.2-positive tumors at 7.55 (2.3-34.8), with a significant difference (p < 0.001). The median TLG was significantly higher in CLDN18.2-negative tumors (231.6) than in CLDN18.2-positive ones (81.14), indicating greater metabolic activity (p = 0.001). Multivariate analysis suggested that SUVmax remained significantly correlated with the status of CLDN18.2 (p = 0.01). CLDN18.2 expression was predicted with an accuracy of 69.9% when the SUVmax value of 10.9 was used as a cutoff point for analysis. Relatively reduced [18F]FDG uptake in metastatic gastric cancers correlates with positive CLDN18.2 expression compared to those with negative CLDN18.2 expression. [18F]FDG PET/CT may be useful for predicting the CLDN18.2 status of gastric cancer and thus aid in optimal treatment decisions. Question The study resolves the clinical issue of determining the correlation between [18F]FDG PET/CT imaging and claudin 18.2 expression in metastatic gastric cancer. Findings Claudin 18.2-positive metastatic gastric cancers exhibit relatively lower [18F]FDG uptake than negative ones. The SUVmax of 10.9 moderately predicts claudin 18.2 expression. Clinical relevance [18F]FDG PET/CT imaging could be a noninvasive way to predict claudin 18.2 status in metastatic gastric cancer, helping to improve personalized treatment plans.

Comparison of 18F-FDG and 68Ga-DOTATATE PET/CT in surgically treated lung carcinoid tumors

Aims: This study aims to compare the efficacy of FDG-18 PET/CT and 68Ga-DOTATATE PET/CT imaging techniques in patients with lung carcinoid tumors, identifying the most appropriate preoperative nuclear medicine technique for diagnosis and staging. Methods: We retrospectively analyzed data from 123 patients who underwent surgery for lung carcinoid tumors at our center between 2009 and 2021. All of the patients were scanned with FDG-18 PET/CT before surgery. In addition to FDG-18 PET/CT, 68Ga-DOTATATE PET/CT scanning was performed in 28 patients: 17 in the preoperative and 11 in the postoperative period. Demographic data, mean higher maximal standard uptake (SUVmax) values of primary mass, lymph nodes and extrathoracic foci, pathologic subtype, and type of surgery were recorded. Compliance with normal distribution for numerical data was assessed using the Shapiro-Wilk test. The Wilcoxon signed-rank test was employed for groups meeting normal distribution to compare continuous numerical variables. The Mann-Whitney U and Kruskal-Wallis tests were used when normal distribution assumptions were unsatisfied. Results: The mean SUVmax value in 68Ga-DOTATATE PET/CT was significantly higher than FDG-18 PET/CT in patients with a lung carcinoid tumor (20 vs 4.4). For 68Ga-DOTATATE PET/CT scan, typical carcinoids had higher mean SUVmax value than atypical carcinoids (26 and 5.6 respectively), and the difference was statistically significant (p=0.002). For that FDG18 PET/CT, on the contrary, the mean SUVmax value was higher in atypical carcinoids than typical carcinoids (5.4 and 3.8, respectively), and the difference was not significant (p=0.126) Conclusion: The SUVmax values from 68Ga-DOTATATE PET/CT and FDG-18 PET/CT in lung carcinoid tumors vary by tumor subtype. 68Ga-DOTATATE PET/CT demonstrates higher SUVmax values in typical carcinoid tumors, indicating its superiority over FDG-18 PET/CT for this subtype. Although 68Ga-DOTATATE PET/CT also shows elevated SUVmax in atypical carcinoid tumors, the difference compared to FDG-18 PET/CT does not reach statistical significance.

ACE and chitotriosidase as possible predictive biomarkers for activity of sarcoidosis in correlation with PET/CT findings

Sarcoidosis is a granulomatous disease which can afflict virtually any tissue in human body, most commonly the mediastinal lymph nodes and lungs. Pathohistological confirmation is the gold standard in establishing a diagnosis; however, determining the activity of the disease requires multiple clinical, radiographic and laboratory procedures. PET/CT scan is considered the gold standard for determining the presence of active granuloma, but has several significant limitations (radioactive material, cost, overall access to device). ACE and chitotriosidase are biomarkers used for diagnosis of sarcoidosis, and could have a place in determining the activity of the disease, when compared with the results of PET/CT scan. We have compared the levels of ACE and chitotriosidase with the levels of SUVmax values in patients with sarcoidosis. SUVmax and chitotriosidase level were significantly correlated both at the baseline and after the follow-up period, regardless of gender, age, duration of disease and radiography stage, while SUVmax and ACE level were not. Chitotriosidase had also shown a significant predictive ability of the decrease of the activity of sarcoidosis represented as the decrease of SUVmax as the effect of therapy in comparison with ACE. In the absence of ideal biomarker for sarcoidosis (high sensitivity, specificity and stability), chitotriosidase can be used in determining the activity of disease, as it had shown a significant correlation to the gold standard- PET/CT scan.

Abstract 4137913: Role of serial evaluation of myocardial inflammatory activity and oxidative stress in determining the therapeutic efficacy of immunosuppression and clinical outcome in patients with cardiac sarcoidosis

Background: Cardiac sarcoidosis (CS) was characterized by formation of granulomas in the heart. Enhancement in myocardial inflammatory activity and oxidative stress is a crucial cause of major cardiovascular adverse events (MACE). Although immunosuppressive therapy is recommended for active CS, there is no established markers for treatment and prognosis. Hypothesis: We hypothesized that the inflammation and oxidative stress in heart were associated with MACE after steroid therapy. Aims: We identified prognostic markers for MACE in patients with CS after steroid therapy. Methods: This study was a prospective observational cohort study. Patients with CS diagnosed according to Japanese criteria were enrolled in this study. Patients with abnormal accumulation of 18 F-FDG in heart were treated with steroids with standard guideline-recommended protocol. 18 F-FDG PET were performed after more than 6 months of induction. Urinary 8-hydroxy-2'-deoxyguanosine (U-8-OHdG), a marker of oxidative DNA damage, and indices of cardiac and renal function were measured. The major outcome was a composite of the first sustained ventricular tachycardia (sVT) /sudden cardiac death (SCD), hospitalization for heart failure, and radiological relapse with exacerbation of clinical manifestation. Results: Fifty consecutive patients with CS underwent steroid therapy and followed up (median follow-up period of 58 months). 39 of 50 patients underwent 18F-FDG PET/CT more than 6 months after steroid therapy. During the follow-up period, 17 of 39 patients showed MACE, consisting of sVT/SCD (N= 11), hospitalization (N= 2) and radiological relapse (N= 4). A Cox proportional-hazard model showed that the U-8-OHdG and SUV max value of FDG-PET were independent predictors of MACE. ROC analysis revealed that the cut-off values of U-8-OHdG and SUV max for predicting the MACE were 11.6 ng/mg Cr (AUC 0.913, sensitivity 86.7%, specificity 90.0%) and 4.64 (AUC 0.878, sensitivity 76.5%, specificity 91.0%), respectively (Fig.1). Patients with a U-8-OHdG ≧11.6 ng/mg Cr or SUV max ≧4.64 had a significantly higher MACE risk (P values for U-8-OHdG and SUV max were both 0.001 by Log Rank analysis) (Fig.2). It is noted that U-8-OHdG &lt;11.6 ng/mg Cr and SUV max &lt;4.64 after steroid therapy indicate the good responses to the immunosuppressive therapy and better prognosis (Fig.3). Conclusion: U-8-OHdG and SUV max may be useful markers in determining the therapeutic efficacy and clinical outcome in patients with CS.

Qualitative and quantitative analysis of 18F-GP1 positron emission tomography in thrombotic cardiovascular disease.

18F-GP1 is a novel highly specific radiotracer that binds to activated platelets and thrombus. We aimed to establish the observer repeatability of coronary, carotid and cerebral 18F-GP1 uptake in patients presenting with acute myocardial infarction or ischaemic stroke. Forty-three patients presenting with acute myocardial infarction or ischaemic stroke underwent hybrid positron emission tomography (PET) and computed tomography (CT) angiography. Qualitative and quantitative assessment of 18F-GP1 uptake was performed on coronary arteries, carotid arteries and brain parenchyma. Qualitative uptake of 18F-GP1 had excellent intraobserver and interobserver agreement, with complete agreement for the presence or absence of visual 18F-GP1 uptake. For quantitative analysis, there were excellent intraclass correlation coefficients for intraobserver repeatability for coronary artery, carotid artery and brain parenchymal SUVmax and TBRmax measurements (all ≥ 0.92). Coronary artery and brain parenchymal analyses showed the strongest agreement in SUVmax values with mean biases of - 0.04 (limits of agreement - 0.21 to 0.20) and 0.02 (limits of agreement - 0.29 to 0.32) respectively. There was good interclass correlation coefficients for interobserver repeatability for coronary artery, carotid artery and brain parenchymal SUVmax and TBRmax measurements (all ≥ 0.89). The strongest interobserver agreement was seen with brain parenchymal SUVmax (mean SUVmax 1.95 ± 0.94) and TBRmax (mean TBRmax 9.55 ± 6.56) with mean biases of - 0.05 (limits of agreement - 0.37 to 0.27) and 0.04 (limits of agreement - 0.59 to 0.52) respectively. Visual qualitative and quantitative 18F-GP1 PET-CT image analyses provide robust and repeatable measurements of activated platelets and thrombi within the coronary arteries, carotid arteries and brain parenchyma.

18F-FDG PET/CT in the diagnosis of infective endocarditis

Abstract Background Increased uptake of 18F-fluorodeoxyglucose (FDG) by positron-emission tomography/computed tomography (PET/CT) is one of the diagnostic criteria for prosthetic valve endocarditis (PVE). However, there is limited data on the diagnostic value of FDG PET/CT in diagnosing native valve endocarditis (NVE) and semi-quantitative parameters of FDG uptake. Purpose The objective of this retrospective study was to evaluate the accuracy of FDG PET/CT and additional value of semi-quantitative measures of FDG uptake in the detection of NVE and PVE. Methods All patients who had undergone FDG PET/CT due to suspected infective endocarditis (IE) at a single tertiary referral center between 2010 and 2020 were identified. Additional patients who underwent FDG PET/CT for detecting an infection focus were included as controls. Clinical reports were evaluated and images were analyzed for maximal standardized uptake value (SUVmax) and target to background ratio (TBR = SUVmax normalized to mean blood pool SUV) around valves. The scan was defined positive based on either clinical reading or previously proposed cut-off values for SUVmax and TBR (&amp;gt;4.2 and &amp;gt;2.1, respectively). The final diagnosis of IE was defined based on all available information in electronic medical records. Results The study cohort included 16 patients with suspected NVE (median age 58 years, 88% male), 24 patients with suspected PVE (median age 72 years, 92% male) and 37 patients who underwent FDG PET/CT for detecting an infectious focus (8 with a prosthetic valve). The final diagnosis was definite IE in 25 (14 PVE), possible IE in 7 (6 PVE), and no IE in 45 (12 with a prosthetic valve). Overall, clinical reading of FDG PET/CT identified 17 (sensitivity 68%) of definite IE with a specificity of 91% and accuracy of 83%. Compared with NVE, the sensitivity of FDG PET/CT was higher in the detection of PVE (46% vs. 86%) whereas specificity was lower (97% vs. 75%) resulting in small difference in accuracy (84% vs. 81%). In PVE, SUVmax had higher sensitivity (93%) than clinical reading, resulting in the same accuracy (81%) despite lower specificity (67%). A combination of either positive clinical reading or positive SUVmax identified all patients with PVE (sensitivity 100%). In NVE, TBR had higher sensitivity (64%) than clinical reading, but accuracy (66%) and specificity (67%) were significantly lower. Conclusions FDG PET/CT shows high sensitivity in the detection of PVE and high specificity in the detection of NVE in a real-world clinical cohort. Semi-quantitative parameters of FDG uptake can improve sensitivity of detecting PVE maintaining diagnostic accuracy. However, in NVE semi-quantitative parameters were associated with a prominent reduction in specificity.

Potentials of pretreatment [18F]FDG PET/CT for non-invasive prediction of the tumor unfavorable pathological indices and microenvironment in NSCLC

PurposeTo investigate pretreatment [18F]FDG PET/CT in predicting tumor pathological features and microenvironment.MethodologyFifty-one patients with histo-pathologically proven non-small cell lung cancer (NSCLC) underwent pretreatment [18F]FDG PET/CT, and their clinicopathological data were collected. PET-derived biomarkers (SUVmax, mean, MTV, and TLG), consolidation-to-tumor ratio (CTR), and histopathological data (tumor grade, differentiation, tumor histological subtype, tumor-infiltrating lymphocytes (TILs), degree of desmoplasia, degree of necrosis, tumor budding, and nuclear grade), as well as a proposed risk stratification pathological scoring system, were all assessed.ResultsA CTR cut-off point of 0.34 was able to discriminate between low- and high-grade tumors with a sensitivity and specificity of 75.9% and 68.2%, respectively (p = 0.012). Low CTR was significantly associated with the tumor pathological subtype “adenocarcinoma,” low nuclear grade, negative tumor necrosis, and low pathological scores, respectively (p < 0.05). No significant associations were observed for CTR with tumor budding score, desmoplasia score, or TILs% (p-values > 0.05). High SUVmax (> 12.64) and high SUVmean (> 4.28) values were significantly associated with SCC tumors (p = 0.023 and 0.04, respectively). SUVmean was significantly associated with cytological differentiation (p = 0.023). A statistical trend was noted for SUVmax concerning nuclear grade and desmoplasia scores (p = 0.068 and 0.061, respectively). No statistically significant associations were revealed for MTV and TLG concerning different pathological features (p-values > 0.05). Primary lung tumors positive for desmoplasia revealed higher metabolic activity regarding SUVmax, with a statistical trend observed (p = 0.072). No statistically significant associations were observed concerning other metabolic parameters (p-values > 0.05).ConclusionPET/CT-derived biomarkers appear promising for predicting tumor unfavorable pathological features and microenvironment in NSCLC.

Enhancing Prostate Cancer Staging: Association of 68Ga-PSMA PET/CT Imaging with Histopathological Grading in Treatment-Naive Patients.

This study aimed to evaluate the correlation between 68Ga-PSMA uptake in PSMA PET/CT in primary prostate cancer (PC) and its histopathological grading (Gleason score and ISUP grade). Additionally, we compared preoperative biopsy histopathological findings with definitive pathology results in radical prostatectomy (RP) specimens. We retrospectively analyzed 86 patients who underwent 68Ga-PSMA PET/CT for primary PC staging, of which 40 patients later underwent radical prostatectomy. PET/CT results, including SUVmax values, were correlated with GS and PSA concentrations. Histopathology reports were analyzed and compared between biopsy and final pathology results following RP. A significant positive correlation was observed between SUVmax and ISUP grades (Pearson's ρ = 0.34, p < 0.001), with higher SUVmax values associated with more advanced grades. A cut-off SUVmax value of 5.64 was determined to predict upstaging in patients, yielding a sensitivity of 76% and a specificity of 60% (AUC = 0.82, 95% CI: 0.70-0.94). Additionally, 57.5% of patients experienced a grade shift following RP, with a 35% upgrade and 22.5% downgrade in ISUP grades. 68Ga-PSMA PET/CT demonstrated high sensitivity in detecting high-risk prostate cancer, particularly in patients with GS > 7 or PSA levels ≥ 10 ng/mL. The findings suggest that this imaging modality may be less effective for the staging of patients with lower GS or PSA values, that is, low-risk PCa. Further prospective studies are necessary to validate these results.

Comparative benefits of Ki and SUV images in lesion detection during PET/CT imaging

BackgroundClinical application of the tracer net influx rate (Ki) imaging in PET/CT remains limited, due to a lack of evidence demonstrating the superiority of Ki images in lesion detection, and guidelines on when to utilize Ki images. This study aims to compare the benefits of Ki and standardized uptake value (SUV) images in lesion detection during PET/CT imaging. By analyzing the performance of both techniques in identifying tumor lesions, the study seeks to provide guidance for the clinical application of Ki images.ResultsThis retrospective study included 134 patients with 244 pathologically confirmed lesions (200 malignant and 44 benign). Patients with a histopathological diagnosis received a weight-based 18F-FDG injection and underwent 60-min total-body PET/CT dynamic imaging. SUV images were reconstructed using data collected from the last 10 min of the scans. Ki images were generated using the Patlak methods with data from minutes 12–60. The background SUVmax, SUVmean, SUVSD, Kimax, Kimean, and KiSD values were recorded. The signal-to-noise ratios of the SUV (SUVSNR) and Ki (KiSNR) images were calculated. The lesion detection rate and sensitivity of the SUV and Ki images were evaluated. The lesion-detection rates were 97.7% (214/219) and 99.5% (218/219) for the SUV and Ki images, respectively (p = .22). Five false-negative lesions on the SUV images were true-positive on the Ki images (3 hepatic malignancies and 2 metastatic lymph nodes). The sensitivity (94.0% vs. 96.0%, p = .22), specificity (41.9% vs. 41.9%, p > .99), accuracy (84.4% vs. 86.1%, p = .61), positive predictive value (87.9% vs. 88.1%, p = .94), negative predictive value (60.0% vs. 69.2%, p = .47), and the area under the curve [0.68 (95% confidence interval, 0.61–0.73) vs. 0.69 (95% confidence interval, 0.62–0.74)] were similar in the SUV and Ki images (all p ≥ .10).ConclusionKi images exhibit benefits in lesion detection compared to SUV images, particularly in organs with high background such as liver. The enhanced contrast provided by Ki imaging is recommended to clinically improve detection rates in such cases.

Comparison of sedation and general anesthesia protocols for 18F-FDG-PET/CT studies in dogs and cats: Musculoskeletal uptake and radiation dose to workers.

In veterinary medicine, PET/CT scans are generally performed with the patient under general anesthesia. The aim of this prospective crossover study was to compare the musculoskeletal uptake of 18F-FDG and radiation doses to workers during PET/CT studies of healthy dogs and cats between sedation and general anesthesia. Volume and maximal standard uptake values (SUVmax) values of abnormal 18F-FDG uptake in the skeletal musculature, presence of misregistration artifact, and radiation doses to workers for each PET/CT study were recorded. Sedation was associated with increased volume of 18F-FDG uptake in the musculature of the thoracic limbs (p=.01), cervical (p=.02), and thoracic (p=.03) spine. Increased volume and SUVmax of the musculature assessed altogether were associated with the lighter degree of sedation (p=.04 for both). A significant decrease in the odds of misregistration artifact was observed for anesthetized animals in comparison with sedated (OR: 0.0, 95% CI: 0.0-0.0, p=.01). Radiation doses to workers were significantly higher for sedation compared with general anesthesia (p=.01) and for the anesthesia technician compared with the nuclear medicine technologist (p=.01). Use of sedation for PET/CT studies in dogs and cats is feasible. However, it is associated with increased physiologic musculoskeletal uptake of 18F-FDG in the thoracic limbs, cervical, and thoracic spine, with increased frequency of misregistration artifact, and with increased radiation doses to workers. These limitations can be overcome by recognition of the uptake pattern and monitoring/rotation of the involved staff at institutions where a high caseload is expected.

The value of quantitative analysis of radionuclide bone SPECT/CT imaging in vertebral compression fracture: a retrospective study

BackgroundMost patients with osteoporosis experience vertebral compression fracture (VCF), which significantly reduces their quality of life. These patients are at a high risk of secondary VCF regardless of treatment. Thus, accurate diagnosis of VCF is important for treating and preventing new fractures. We aimed to investigate the diagnostic and predictive value of quantitative bone imaging techniques for fresh VCF.MethodsFrom November 2021 to March 2023, 34 patients with VCF were enrolled in this study, all of whom underwent routine 99mTc-MDP whole-body bone planar scan and local SPECT/CT imaging. The maximum standard uptake value (SUVmax) of 57 fresh VCF, 57 normal adjacent vertebrae, and 19 old VCF were measured. Based on the site of the fracture, fresh VCFs were regrouped into the intervertebral-type group and the margin-type group. Meanwhile, 52 patients who had no bone metastasis or VCFs in their bone scan were assigned to the control group. The SUVmax of 110 normal vertebral bodies and 10 old VCFs in the control group were measured.ResultsThe median SUVmax of fresh VCF was 19.80, which was significantly higher than the SUVmax of other groups. The receiver operator characteristic (ROC) curve showed that the cut-off value of SUVmax was 9.925 for diagnosing fresh VCF. The SUVmax in the intervertebral-type group was significantly higher than that in the margin-type group (P = 0.04). The SUVmax of normal vertebrae was higher among patients than among the control group (P<0.01), but the CT HU value showed no significant difference.ConclusionThe quantitative technique of bone SPECT/CT has a significant value in diagnosing fresh VCF. It can also determine the severity of fractures. In addition, whether the SUVs of the vertebrae adjacent to the fractured vertebra can predict re-fracture deserves further studies.

Pre-operative dual-time-point [18F]FET PET differentiates CDKN2A/B loss and PIK3CA mutation status in adult-type diffuse glioma: a single-center prospective study.

While [18F]FET PET plays a complementary role in glioma imaging, it needs to be more comprehensively understood for improved characterization of glioma prior to surgery given the evolving landscape of molecular neuropathology. Thus, we investigated the utility of pre-operative dual-time-point [18F]FET PET in correlation with next-generation sequencing (NGS) data in patients with adult-type diffuse glioma (ADG). Adult patients who were suspected to have primary glioma were prospectively recruited between June 2021 and January 2024. They underwent pre-operative dual-time-point static PET/CT at 20min (early) and 80min (delay) after [18F]FET injection. Semi-quantitative parameters of the hottest lesion (SUVmax) of tumour and the hottest lesion-to-normal brain ratio (TBRmax) were assessed from each summed image. Furthermore, the percentage changes (△) of SUVmax and TBRmax between two images were calculated. Histopathology of glioma was determined according to the 2021 WHO classification and NGS data. This study investigated a dozen genes in 76 patients, of whom 51 had isocitrate dehydrogenase (IDH)-wild-type glioblastoma, 13 had IDH-mutant astrocytoma, and 12 had IDH-mutant oligodendroglioma. Every tumour was [18F]FET-avid having TBRmax more than 1.6. Patients with CDKN2A/B loss had significantly higher values of SUVmax (5.7 ± 1.6 vs. 4.7 ± 1.3, p = 0.004; 5.0 ± 1.4 vs. 4.4 ± 1.2, p = 0.026) and TBRmax (6.5 ± 1.8 vs. 5.1 ± 1.7, p = 0.001; 5.3 ± 1.5 vs. 4.3 ± 1.3, p = 0.004) in both scans than patients without CDKN2A/B loss, even after adjustment for age, MRI enhancement, tumor grade and type of pathology. Furthermore, patients with PIK3CA mutation (16.2 ± 11.8 vs. 6.7 ± 11.6, p = 0.007) had significantly higher △SUVmax than patients without PIK3CA mutation, even after adjustment for age, MRI enhancement, tumor grade, and type of pathology. Among the dozen genes investigated in this prospective study in patients with ADG, we found out that CDKN2A/B loss and PIK3CA mutation status could be differentiated by pre-operative dual-time-point [18F]FET PET/CT.

The prognostic role of whole-body volumetric positron emission tomography/computed tomography parameters in treatment naive colorectal cancer patients with liver metastases.

The present study aimed to predict the prognostic role of quantitative 18F-fluorodeoxyglucose PET/computed tomography parameters such as maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) obtained from primary tumor, lymph node metastases, and liver metastasis (LM) in patients with colorectal LM (CLM). The research was designed as a retrospective study and 66 patients with CLM were enrolled between January 2017 and December 2018. Primary tumor SUVmax (PSUVmax), liver SUVmax (LSUVmax), and lymph node SUVmax (LnSUVmax) values obtained from the primary tumor, liver, and lymph nodes were recorded. In addition, total MTV (TMTV) and total TLG (TTLG) values were obtained by summing the values obtained from the primary tumor (PMTV and PTLG), lymph nodes (LnMTV and LnTLG), and liver (LMTV and LTLG). Univariate and multivariate Cox regression analysis was used to measure the effects of prognostic variables on mortality and survival. In univariate Cox regression analysis, PMTV (P = 0.001), LnMTV (P = 0.008), LnTLG (P = 0.008), LnSUVmax (P = 0.047), and TTLG (P = 0.038) were identified as prognostic factors for overall survival. No statistically significant relationship was found between MTV and TLG values of LM and overall survival. In multivariate analysis, PMTV (P = 0.022) was identified as an independent prognostic factor. In conclusion, our study demonstrated that the PMTV value used in evaluating treatment-naive patients diagnosed with CLM is an independent prognostic factor for survival. Our results need to be confirmed with more studies involving more patients.

Maximum standardized uptake value-to-tumor size ratio in fluorodeoxyglucose F18 positron emission tomography/computed tomography: a simple prognostic parameter for non-small cell lung cancer.

By correcting the effect of tumor size on metabolic activity, the maximum standardized uptake value-to-tumor size (SUVmax:tumor size) ratio on fluorodeoxyglucose F18 positron emission tomography (18F-FDG PET)/computed tomography (CT) scans can be a prognostic parameter of non-small cell lung cancer (NSCLC). The current study evaluates the prognostic value of SUVmax:tumor size ratio on pretreatment 18F-FDG PET/CT scans in patients with NSCLC. Furthermore, the SUVmax:tumor size ratio is compared with other established PET parameters. This study included 108 patients with NSCLC who underwent pretreatment 18F-FDG PET/CT scans and curative lung surgery. The associations between the SUVmax:tumor size ratio and other conventional PET parameters were investigated. The recurrence-free survival according to the SUVmax:tumor size ratio was also analyzed. In addition, the SUVmax:tumor size ratio was compared according to postoperative pathologic findings. In total, 72 (66.7%) of the 108 participants presented with adenocarcinoma (ADC). Nineteen (17.6%) patients experienced recurrence during a median follow-up period of 32.3 months. The median SUV max:tumor size ratio was 2.37 (1.23 for ADCs and 3.90 for other histologic types). The SUVmax:tumor size ratio was associated with SUVmax and mean SUV, as well as metabolic tumor volume and total lesion glycolysis. Patients with an SUVmax:tumor size ratio higher than the median had a worse recurrence outcome than those with an SUVmax:tumor size ratio lower than the median. Participants with ADC who presented with lymphovascular invasion had a higher SUVmax:tumor size ratio than those without. The presence of lymph node metastasis and advanced histologic grade were associated with a high SUVmax:tumor size ratio in patients with ADC. The SUVmax:tumor size ratio on pretreatment 18F-FDG PET/CT scans was associated with aggressive tumor behavior and poor outcome in NSCLCs, particularly ADC. The SUVmax:tumor size ratio on pretreatment 18F-FDG PET/CT scans has a prognostic value in patients with NSCLCs, especially ADC.

Assessment of pulmonary nodules using [18F]-FDG PET/CT in deep inspiration breath-hold

The characterization of pulmonary nodules (PN) is a primary indication for [18F]-FDG PET/CT. However, respiratory movements hinder this characterization, especially for PN located in the lower lobes. Various methods have been developed to improve image resolution. ObjectiveOur objective was to compare the diagnostic efficacy of [18F]-FDG PET/CT in deep inspiration breath-hold (DIBH) versus free-breathing corrected by software, in the evaluation of PN. MethodsWe prospectively analyzed 51 patients to assess PN using [18F]-FDG PET/CT in DIBH and free-breathing corrected by software. A total of 84 nodules with an average size of 10 mm were analyzed, with pathological anatomy or medical treatment decisions by a multidisciplinary tumor board used as reference. ResultsA total of 84 PN were evaluated, comparing those in DIBH versus free-breathing, finding statistically significant differences in SUVmax values (P < .05) (mean SUVmax 3.7 in free-breathing vs. 5.33 in DIBH). When analyzed by location in lobes, we did not find statistically significant differences, though there was a trend towards higher SUVmax values in the lower lobes. [18F]-FDG PET/CT in DIBH showed high sensitivity (95%) and negative predictive value (NPV) (92%), indicating it may be a promising tool for PN characterization. ConclusionsThe acquisition of [18F]-FDG PET/CT in DIBH significantly improves the sensitivity and diagnostic efficacy in the assessment of PN. Although no statistically significant differences were found based on location, there is a potential benefit for the lower lobes. These findings could support its use in clinical practice.

Application of Dynamic [18F]FDG PET/CT Multiparametric Imaging Leads to an Improved Differentiation of Benign and Malignant Lung Lesions.

To evaluate the potential of whole-body dynamic (WBD) 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) multiparametric imaging in the differential diagnosis between benign and malignant lung lesions. We retrospectively analyzed WBD PET/CT scans from patients with lung lesions performed between April 2020 and March 2023. Multiparametric images including standardized uptake value (SUV), metabolic rate (MRFDG) and distribution volume (DVFDG) were visually interpreted and compared. We adopted SUVmax, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) for semi-quantitative analysis, MRmax and DVmax values for quantitative analysis. We also collected the patients' clinical characteristics. The variables above with P-value < 0.05 in the univariate analysis were entered into a multivariate logistic regression. The statistically significant metrics were plotted on receiver-operating characteristic (ROC) curves. A total of 60 patients were included for data evaluation. We found that most malignant lesions showed high uptake on MRFDG and SUV images, and low or absent uptake on DVFDG images, while benign lesions showed low uptake on MRFDG images and high uptake on DVFDG images. Most malignant lesions showed a characteristic pattern of gradually increasing FDG uptake, whereas benign lesions presented an initial rise with rapid fall, then kept stable at a low level. The AUC values of MRmax and SUVmax are 0.874 (95% CI: 0.763-0.946) and 0.792 (95% CI: 0.667-0.886), respectively. DeLong's test showed the difference between the areas is statistically significant (P < 0.001). Our study demonstrated that dynamic [18F]FDG PET/CT imaging based on the Patlak analysis was a more accurate method of distinguishing malignancies from benign lesions than conventional static PET/CT scans.

Role of PET/CT in improving the cost effectiveness of nimotuzumab in nasopharyngeal carcinoma.

This study aims to use the maximum standardised uptake value (SUVmax) of 18F-fluorodeoxyglucose positron emission tomography to improve the cost effectiveness of nimotuzumab (NTZ) in locoregionally advanced nasopharyngeal carcinoma (LA-NPC). Two hundred and forty-eigh patients with LA-NPC, who met the inclusion criteria, were recruited from January 2012 to June 2019. The survival differences and independent factors were assessed using the Kaplan-Meier method and by Cox proportional hazards regression analysis. A cost effectiveness analysis was performed. The optimal cut-off value for SUVmax was 12.92. Multivariable analysis indicated a prognostic significance of overall survival (OS) for the NTZ treatment (p = 0.023) and SUVmax (p = 0.014). The exploratory subgroup survival analysis revealed that LA-NPC patients with SUVmax > 12.92 treated with concurrent chemoradiotherapy (CCRT) and NTZ had a significantly improved 3-year OS compared to patients treated with CCRT alone (96.2 vs 73.2%, p = 0.047). Furthermore, the treatment cost for NTZ was $6,317.61. This incurred an additional cost of $274.68 for every 1% increase in OS. For patients with LA-NPC with SUVmax > 12.92, the addition of NTZ to CCRT can improve OS and is cost effective.

Negative-predictive value of SUVmax for Ascertaining the efficacy of osimertinib in EGFR mutation-positive non-small cell lung cancer

BackgroundFluorine-18 2-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) is routinely used to stage non-small cell lung cancer (NSCLC). However, whether 18F-FDG accumulation in primary tumors affects the efficacy of osimertinib in patients with epidermal growth factor receptor (EGFR) mutation-positive NSCLC remains unclear. MethodsWe retrospectively investigated 74 patients with advanced or postoperative recurrent EGFR mutation-positive NSCLC who underwent 18F-FDG PET/CT and were treated with osimertinib as first-line therapy between September 2018 and March 2023 at Kumamoto University Hospital. The maximum standardized uptake value (SUVmax) of each primary tumor was measured, and the patients were divided into two groups according to the median SUVmax. The effects of SUVmax on progression-free survival (PFS) and overall survival (OS) were assessed using a multivariate Cox proportional hazards model. ResultsThe median SUVmax was 8.2 (interquartile range: 5.5–11.4). The median PFS in the high SUVmax group (≥8.2) was significantly shorter than that in the low SUVmax group (<8.2). The respective median PFSs were 11.2 months (95% confidence interval [CI]: 3.1–19.3 months) vs. 22.9 months (95% CI: 12.4–33.4 months) (P = 0.015), although the OS values did not differ significantly. Multivariate analysis showed that a high SUVmax was an independent negative predictive factor for PFS in patients treated with osimertinib (hazard ratio, 2.25; 95% CI: 1.15–4.39, P = 0.017). ConclusionsHigh primary-lesion SUVmax in patients with EGFR mutation-positive NSCLC correlated with shorter PFS with first-line osimertinib therapy, suggesting that SUVmax is a useful predictive marker for the antitumor efficacy of osimertinib.