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Japanese Journal of Clinical Oncology Jun 2024Proton beams deposit energy along their path, abruptly stopping and generating various radioactive particles, including positrons, along their trajectory. In comparison...
BACKGROUND
Proton beams deposit energy along their path, abruptly stopping and generating various radioactive particles, including positrons, along their trajectory. In comparison with traditional proton beam therapy, scanning proton beam therapy is effective in delivering proton beams to irregularly shaped tumors, reducing excessive radiation exposure to the alimentary tract during the treatment of liver cancer.
METHODS
In this study, we utilized positron emission tomography/computed tomography (PET/CT) imaging to assess the total amount of radiation to the alimentary tract during liver cancer treatment with proton beam therapy, involving the administration of complex irradiation in 13 patients.
RESULTS
This approach resulted in the prevention of excess radiation. The planned radiation restraint doses for the colon exhibited a significant correlation with the PET values of the colon (correlation coefficient 0.8384, P = .0003). Likewise, the scheduled radiation restraint doses for the gastroduodenum were correlated with the PET values of the gastroduodenum (correlation coefficient 0.5397, P = .0569).
CONCLUSIONS
PET/CT conducted after proton beam therapy is useful for evaluating excess radiation in the alimentary tract. Proton beam therapy in liver cancer, assessed via PET/CT, effectively reduced alimentary tract radiation, which is vital for optimizing treatments and preventing excess exposure.
PubMed: 38943456
DOI: 10.1093/jjco/hyae085 -
Otolaryngology--head and Neck Surgery :... Jun 2024To assess the diagnostic accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography (FDG-PET/CT) in detecting second primary... (Review)
Review
OBJECTIVE
To assess the diagnostic accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography (FDG-PET/CT) in detecting second primary malignancies (SPMs) in patients with treatment naïve head and neck squamous cell carcinoma (HNSCC).
DATA SOURCES
Medline, Embase, Cochrane Library, and Scopus searched from 1946 to December 2022.
REVIEW METHODS
Studies reporting the performance of FDG-PET/CT in patients with treatment-naïve, index HNSCC for detection of SPMs were included. The reference standard was histopathology, clinical follow-up over the duration of study, and other imaging modalities. Multiple investigators completed depth full-text analysis. Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines were followed. Methodologic and diagnostic accuracy data were abstracted independently by multiple investigators. Risk of bias assessment was conducted using the Quality Assessment of Diagnostic Accuracy Studies tool independently. Bivariate random-effects model meta-analysis and multivariable meta-regression modeling were used.
RESULTS
Seventeen studies examining 4624 patients with a total of 475 SPMs were included in the final analysis. Eleven studies were found to be at low risk for bias, while the rest were in the high-risk category. FDG-PET/CT demonstrated pooled sensitivity and specificity of 0.73 (95% confidence interval [CI]: 0.49-0.88) and 0.99 (95% CI: 0.98-1.00) in detecting SPMs. Further subsite analysis revealed varied diagnostic performance across different anatomical regions, with sensitivity and specificity of esophageal SPMs being 0.47 (0.30-0.64) and 0.99 (0.98-1.00), and sensitivity and specificity of 0.86 (0.73-0.94) and 0.99 (0.98-1.00) for head and neck SPMs. Finally, this imaging modality showed sensitivity and specificity of 0.92 (0.84-0.96) and 0.99 (0.98-1.00) for lung SPMs.
CONCLUSION
The findings of this study suggest varied accuracy of FDG-PET/CT in detecting SPMs during initial workup for HNSCC, highlighting the importance of screening modalities such as esophagoscopy in high-risk patients.
PubMed: 38943453
DOI: 10.1002/ohn.879 -
Nigerian Journal of Clinical Practice Jun 2024Some parameters of 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) can predict tumor chemosensitivity and survival in...
The Prognostic Significance of Tumor SUVmax Value in Pre- and Post-Chemoradiotherapy 18F-FDG PET/CT Imaging in Patients with Localized and Advanced Head and Neck Squamous Cell Carcinoma.
BACKGROUND
Some parameters of 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) can predict tumor chemosensitivity and survival in patients with head and neck squamous cell carcinoma (HNSCC).
AIM
The aim of the study was to investigate the prognostic value of pre- and post-treatment maximum standardized uptake values (SUVmax) in 18F-FDG PET/CT imaging for predicting mortality in patients with HNSCC, as well as its prognostic value in terms of disease progression, overall survival (OS), and progression-free survival (PFS).
METHODS
This retrospective study included 37 patients with a histopathological diagnosis of HNSCCs between 2015 and 2018. In patients with HNSCC, the first 18F-FDG PET/CT imaging was performed for pre-treatment staging, and the second imaging was performed to evaluate post-treatment response. In these imaging studies, SUVmax values of the primary tumor before and after treatment were determined. After the second imaging, patients were re-evaluated and followed up. ROC analysis was used to determine the predictive value of 18F-FDG PET/CT SUVmax parameters in terms of death and progression, and Cox regression analysis was used to investigate the prognostic value in terms of OS and PFS.
RESULTS
Cut-off value 15 for SUVmax1 (pre-treatment) had a significant predictive value for mortality (P = 0.02). Cut-off value 3.1 for SUVmax2 (post-treatment) had a significant predictive value for progression (P = 0.024). In univariate analysis, both SUVmax1 and SUVmax2 values were significant prognostic factors for OS (P = 0.047, P = 0.004). However, for PFS, only the SUVmax2 value was a significant prognostic factor (P = 0.001).
CONCLUSION
SUVmax1 value of the primary tumor at diagnosis in HNSCC patients has a predictive value for mortality and a prognostic value for OS. However, the SUVmax2 value in the primary tumor after treatment is a predictive factor for progression and a prognostic factor for both OS and PFS.
Topics: Humans; Fluorodeoxyglucose F18; Male; Positron Emission Tomography Computed Tomography; Female; Middle Aged; Retrospective Studies; Squamous Cell Carcinoma of Head and Neck; Prognosis; Head and Neck Neoplasms; Aged; Chemoradiotherapy; Adult; Radiopharmaceuticals; Predictive Value of Tests; Disease Progression
PubMed: 38943299
DOI: 10.4103/njcp.njcp_856_23 -
Archivos de Bronconeumologia May 2024The maximum standardised uptake value (SUVmax) is a widely utilised metric in positron emission tomography/computed tomography for clinically staging non-small-cell lung...
OBJECTIVE
The maximum standardised uptake value (SUVmax) is a widely utilised metric in positron emission tomography/computed tomography for clinically staging non-small-cell lung cancer (NSCLC), yet the reliability of SUVmax remains controversial. We herein aimed to assess the effectiveness of semi-quantitative parameters, encompassing size, SUVmax, metabolic tumour volume (MTV), total lesion glycolysis (TLG) and heterogeneity factor (HF), in evaluating both primary tumours and lymph nodes (LNs) on positron emission tomography/computed tomography. A novel scoring system was devised to appraise the role of semi-quantitative parameters and visually evaluate LNs for nodal staging.
MATERIALS AND METHODS
Patients with pathological NSCLC, diagnosed between 2014 and 2019 and clinically staged I-III, were enrolled in the study. Patient demographics, including age, sex, tumour location, diameter, tumour-node-metastasis stage, as well as SUVmax, MTV, TLG and HF parameters of primary tumours and LNs, were documented.
RESULTS
The analysis comprised 319 patients and 963 LNs. Patients had a mean age of 61.62 years, with 91.5% being male. Adenocarcinoma exhibited a histological association with LN metastasis (P=0.043). The study findings revealed that tumour size, SUVmax, MTV, TLG and HF did not significantly affect the detection of LN metastasis. Conversely, non-squamous cell carcinoma, LNs exhibiting higher FDG levels than the liver, LN size, SUVmax, MTV and TLG were identified as risk factors (P<0.0001). The identified cut-off values were 1.05cm for LN size, 4.055 for SUVmax, 1.805cm for MTV and 5.485 for TLG. The scoring system incorporated these parameters, and visual assessment indicated that a score of ≥3 increased the risk of metastasis by 14.33 times.
CONCLUSION
We devised a novel scoring system and demonstrated that LNs with a score of ≥3 in patients with NSCLC have a high likelihood of metastasis. This innovative scoring system can serve as a valuable tool to mitigate excessive and extreme measures in the assessment of invasive pathological staging.
PubMed: 38942660
DOI: 10.1016/j.arbres.2024.05.020 -
Korean Journal of Radiology Jul 2024To develop and validate a preoperative risk score incorporating carbohydrate antigen (CA) 19-9, CT, and fluorine-18-fluorodeoxyglucose (F-FDG) PET/CT variables to...
Predicting Recurrence-Free Survival After Upfront Surgery in Resectable Pancreatic Ductal Adenocarcinoma: A Preoperative Risk Score Based on CA 19-9, CT, and F-FDG PET/CT.
OBJECTIVE
To develop and validate a preoperative risk score incorporating carbohydrate antigen (CA) 19-9, CT, and fluorine-18-fluorodeoxyglucose (F-FDG) PET/CT variables to predict recurrence-free survival (RFS) after upfront surgery in patients with resectable pancreatic ductal adenocarcinoma (PDAC).
MATERIALS AND METHODS
Patients with resectable PDAC who underwent upfront surgery between 2014 and 2017 (development set) or between 2018 and 2019 (test set) were retrospectively evaluated. In the development set, a risk-scoring system was developed using the multivariable Cox proportional hazards model, including variables associated with RFS. In the test set, the performance of the risk score was evaluated using the Harrell C-index and compared with that of the postoperative pathological tumor stage.
RESULTS
A total of 529 patients, including 335 (198 male; mean age ± standard deviation, 64 ± 9 years) and 194 (103 male; mean age, 66 ± 9 years) patients in the development and test sets, respectively, were evaluated. The risk score included five variables predicting RFS: tumor size (hazard ratio [HR], 1.29 per 1 cm increment; < 0.001), maximal standardized uptake values of tumor ≥ 5.2 (HR, 1.29; = 0.06), suspicious regional lymph nodes (HR, 1.43; = 0.02), possible distant metastasis on F-FDG PET/CT (HR, 2.32; = 0.03), and CA 19-9 (HR, 1.02 per 100 U/mL increment; = 0.002). In the test set, the risk score showed good performance in predicting RFS (C-index, 0.61), similar to that of the pathologic tumor stage (C-index, 0.64; = 0.17).
CONCLUSION
The proposed risk score based on preoperative CA 19-9, CT, and F-FDG PET/CT variables may have clinical utility in selecting high-risk patients with resectable PDAC.
Topics: Humans; Male; Fluorodeoxyglucose F18; Female; Positron Emission Tomography Computed Tomography; Middle Aged; Carcinoma, Pancreatic Ductal; Aged; Pancreatic Neoplasms; Retrospective Studies; Radiopharmaceuticals; CA-19-9 Antigen; Tomography, X-Ray Computed; Neoplasm Recurrence, Local; Risk Assessment; Disease-Free Survival; Predictive Value of Tests
PubMed: 38942458
DOI: 10.3348/kjr.2023.1235 -
NeuroImage Jun 2024The prediction of Alzheimer's disease (AD) progression from its early stages is a research priority. In this context, the use of Artificial Intelligence (AI) in AD has...
BACKGROUND
The prediction of Alzheimer's disease (AD) progression from its early stages is a research priority. In this context, the use of Artificial Intelligence (AI) in AD has experienced a notable surge in recent years. However, existing investigations predominantly concentrate on distinguishing clinical phenotypes through cross-sectional approaches. This study aims to investigate the potential of modeling additional dimensions of the disease, such as variations in brain metabolism assessed via [F]-fluorodeoxyglucose positron emission tomography (FDG-PET), and utilize this information to identify patients with mild cognitive impairment (MCI) who will progress to dementia (pMCI).
METHODS
We analyzed data from 1,617 participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) who had undergone at least one FDG-PET scan. We identified the brain regions with the most significant hypometabolism in AD and used Deep Learning (DL) models to predict future changes in brain metabolism. The best-performing model was then adapted under a multi-task learning framework to identify pMCI individuals. Finally, this model underwent further analysis using eXplainable AI (XAI) techniques.
RESULTS
Our results confirm a strong association between hypometabolism, disease progression, and cognitive decline. Furthermore, we demonstrated that integrating data on changes in brain metabolism during training enhanced the models' ability to detect pMCI individuals (sensitivity=88.4%, specificity=86.9%). Lastly, the application of XAI techniques enabled us to delve into the brain regions with the most significant impact on model predictions, highlighting the importance of the hippocampus, cingulate cortex, and some subcortical structures.
CONCLUSION
This study introduces a novel dimension to predictive modeling in AD, emphasizing the importance of projecting variations in brain metabolism under a multi-task learning paradigm.
PubMed: 38942101
DOI: 10.1016/j.neuroimage.2024.120695 -
British Journal of Hospital Medicine... Jun 2024Breast leukaemia (BL) is a rare breast malignancy that is treated differently from other malignant conditions. However, it is easily confused with other conditions;...
Breast leukaemia (BL) is a rare breast malignancy that is treated differently from other malignant conditions. However, it is easily confused with other conditions; therefore, how to accurately diagnose is crucial. We retrospectively analysed the imaging findings of 13 patients to provide a diagnostic reference. From January 2015 to April 2023, 13 patients with BL confirmed by biopsy who underwent imaging in Peking University People's hospital were retrospectively analysed. The imaging findings obtained via ultrasound (US), mammography (MMG), magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT) were analysed, and the detection rates of these methods for diagnosing BL were compared. Twenty-nine lesions were detected in the 13 patients. These patients presented with palpable masses or breast swelling several months after treatment for leukaemia, mainly involving the bilateral breasts. Ultrasonography was performed for 13 patients, and all lesions were detected. Most of the identified masses were hypoechoic and had indistinct boundaries, irregular shapes, no enhancement of the posterior echo, and no abundant blood flow. MMG was performed for five patients, revealing breast masses, architectural distortion, and no abnormalities. MRI was performed for four patients, and all lesions were detected; most of the lesions were hypointense on T1-weighted imaging and hyperintense on T2-weighted imaging and diffusion-weighted imaging, with a decreased apparent diffusion coefficient and inhomogeneous enhancement. The enhancement curves were mostly inflow patterns. PET/CT was performed for four patients; two patients had hypermetabolism, and the other two had no obvious radioactive uptake. Compared to MMG and PET/CT, US and MRI have higher detection rates. Furthermore, compared to MRI, US is inexpensive, convenient and efficient; therefore, it should be the first choice for diagnosing BL.
Topics: Humans; Female; Breast Neoplasms; Middle Aged; Adult; Retrospective Studies; Positron Emission Tomography Computed Tomography; Magnetic Resonance Imaging; Mammography; Ultrasonography, Mammary; Leukemia; Aged
PubMed: 38941971
DOI: 10.12968/hmed.2024.0101 -
Molecular Pharmaceutics Jun 2024Lymphocyte activation gene 3 (LAG-3) has attracted much attention as a potentially valuable immune checkpoint. Individual identification of LAG-3 expression at screening...
Lymphocyte activation gene 3 (LAG-3) has attracted much attention as a potentially valuable immune checkpoint. Individual identification of LAG-3 expression at screening and during treatment could improve the successful implementation of anti-LAG-3 therapies. HuL13 is a human IgG1 monoclonal antibody that binds to the LAG-3 receptor in T cells. Here, we used [Zr]Zr-labeled HuL13 to delineate LAG-3 T-cell infiltration into tumors via positron emission tomography (PET) imaging. A549/LAG-3 cells, which stably express LAG-3, were generated by infection with lentivirus. The uptake of [Zr]Zr-DFO-HuL13 in A549/LAG-3 cells was greater than that in the negative control (A549/NC) cells at each time point. The equilibrium dissociation constant () of [Zr]Zr-DFO-HuL13 for the LAG-3 receptor was 8.22 nM. PET imaging revealed significant uptake in the tumor areas of A549/LAG-3 tumor-bearing mice from 24 h after injection (SUVmax = 2.43 ± 0.06 at 24 h). As a proof of concept, PET imaging of the [Zr]Zr-DFO-HuL13 tracer was further investigated in an MC38 tumor-bearing humanized LAG-3 mouse model. PET imaging revealed that the [Zr]Zr-DFO-HuL13 tracer specifically targets human LAG-3 expressed on tumor-infiltrating lymphocytes (TILs). In addition to the tumors, the spleen was also noticeably visible. Tumor uptake of the [Zr]Zr-DFO-HuL13 tracer was lower than its uptake in the spleen, but high uptake in the spleen could be reduced by coinjection of unlabeled antibodies. Coinjection of unlabeled antibodies increases tracer activity in the blood pool, thereby improving tumor uptake. Dosimetry evaluation of the healthy mouse models revealed that the highest absorbed radiation dose was in the spleen, followed by the liver and heart wall. In summary, these studies demonstrate the feasibility of using the [Zr]Zr-DFO-HuL13 tracer for the detection of LAG-3 expression on TILs. Further clinical evaluation of the [Zr]Zr-DFO-HuL13 tracer may be of significant help in the stratification and management of patients suitable for anti-LAG-3 therapy.
PubMed: 38941565
DOI: 10.1021/acs.molpharmaceut.4c00343 -
Revista de La Facultad de Ciencias... Jun 2024schwannomas are benign and common soft tissue tumors. They are usually asymptomatic and are discovered for other reasons.
INTRODUCTION
schwannomas are benign and common soft tissue tumors. They are usually asymptomatic and are discovered for other reasons.
MATERIALS
we present the case of an 82-year-old male patient with a recent diagnosis of moderately differentiated adenocarcinoma of the colon and a hypermetabolic periaortic nodule as an incidental finding.
RESULTS
percutaneous biopsy of the periaortic nodule confirmed the diagnosis of schwannoma. At one year of follow-up, growth of the schwannoma has been demonstrated. There are no signs of progression of his oncological disease.
CONCLUSIONS
schwannomas are benign tumors, rarely found in the retroperitoneum and can be sources of false-positive positron emission tomography results.
Topics: Humans; Male; Retroperitoneal Neoplasms; Neurilemmoma; Aged, 80 and over; False Positive Reactions; Diagnosis, Differential; Adenocarcinoma; Colorectal Neoplasms; Positron-Emission Tomography
PubMed: 38941230
DOI: 10.31053/1853.0605.v81.n2.38014 -
IEEE Transactions on Image Processing :... Jun 2024Combining dual-energy computed tomography (DECT) with positron emission tomography (PET) offers many potential clinical applications but typically requires expensive...
Combining dual-energy computed tomography (DECT) with positron emission tomography (PET) offers many potential clinical applications but typically requires expensive hardware upgrades or increases radiation doses on PET/CT scanners due to an extra X-ray CT scan. The recent PET-enabled DECT method allows DECT imaging on PET/CT without requiring a second X-ray CT scan. It combines the already existing X-ray CT image with a 511 keV γ-ray CT (gCT) image reconstructed from time-of-flight PET emission data. A kernelized framework has been developed for reconstructing gCT image but this method has not fully exploited the potential of prior knowledge. Use of deep neural networks may explore the power of deep learning in this application. However, common approaches require a large database for training, which is impractical for a new imaging method like PET-enabled DECT. Here, we propose a single-subject method by using neural-network representation as a deep coefficient prior to improving gCT image reconstruction without population-based pre-training. The resulting optimization problem becomes the tomographic estimation of nonlinear neural-network parameters from gCT projection data. This complicated problem can be efficiently solved by utilizing the optimization transfer strategy with quadratic surrogates. Each iteration of the proposed neural optimization transfer algorithm includes: PET activity image update; gCT image update; and least-square neural-network learning in the gCT image domain. This algorithm is guaranteed to monotonically increase the data likelihood. Results from computer simulation, real phantom data and real patient data have demonstrated that the proposed method can significantly improve gCT image quality and consequent multi-material decomposition as compared to other methods.
PubMed: 38941203
DOI: 10.1109/TIP.2024.3418347