Revista espanola de medicina nuclear e imagen molecular最新文献

Objective: To assess whether parameters derived from ¹⁸F-FDG PET/CT imaging could be used for prognostic evaluation in pediatric patients with bone and soft tissue sarcomas.

Material and methods: This retrospective study included pediatric patients diagnosed with sarcoma who underwent ¹⁸F-FDG PET/CT between February 2013 and January 2021. A total of 63 patients were evaluated. Anatomical tumor volume, standardized uptake values (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured. Progression-free survival (PFS) and overall survival (OS) were calculated. Cox regression analysis was performed to identify independent predictors.

Results: The mortality rate was 31.7%, and the median OS was 54.9 months. Lung (p<0.001) and lymph node metastases (p=0.049) were associated with shorter OS. Younger age at diagnosis (p=0.014), higher anatomical tumor volume (p=0.002), and lung metastasis (p=0.004) were independently associated with increased mortality risk. High MTV was independently associated with higher progression risk (p<0.001).

Conclusion: Anatomical tumor volume and lung metastasis predict mortality, while MTV predicts progression in pediatric sarcoma. Further prospective studies are needed to validate these findings.

Objectives: Programmed death-ligand 1 (PD-L1) expression serves as a critical biomarker for selecting patients eligible for treatment with immune checkpoint inhibitors. Herein, we investigated the association between PD-L1 expression and various FDG PET/CT-derived metabolic parameters in patients with non-small cell lung cancer (NSCLC).

Materials and methods: This retrospective study included 81 NSCLC patients who underwent pre-treatment F-18 FDG PET/CT imaging and histopathological evaluation of PD-L1 expression. PD-L1 tumour proportion score (TPS) was determined using the SP263 immunohistochemical assay. PD-L1 positivity was defined as TPS ≥ 1%. Quantitative PET/CT parameters-SUVmax, SUVmean, SULpeak, SULmax, metabolic tumor volume (MTV), total lesion glycolysis (TLG), and heterogeneity indices (coefficient of variation [COV] and SUV-based heterogeneity index [HI])-were analyzed in relation to PD-L1 TPS.

Results: PD-L1 positivity was identified in 30 patients (37%). Although SUVmax, SUVmean, SULpeak, and SULmax values tended to be higher in PD-L1-positive patients, these differences were not statistically significant. Conversely, MTV and TLG were higher in the PD-L1-negative group. Among all parameters, HI was significantly elevated in the PD-L1-positive group (P = .031), and remained significant across PD-L1 expression strata (P = .037). In metastatic patients, HI and COV showed significant positive correlation with PD-L1 expression (r = 0.34 and 0.33, respectively). ROC analysis identified a HI cut-off of 1.59 to predict PD-L1 positivity with 90% sensitivity and 50% specificity (AUC = 0.674).

Conclusions: Tumor heterogeneity indices, particularly HI and COV derived from FDG PET/CT, demonstrated stronger predictive value for PD-L1 expression than conventional metabolic parameters. These findings suggest that metabolic heterogeneity may serve as a useful noninvasive imaging biomarker for guiding immunotherapy in NSCLC.

Objective: This study aimed to determine the functional expression of somatostatin receptors in patients with primary brain tumors including meningiomas and gliomas using ^99mTc-HYNIC-octreotide SPECT/CT imaging.

Method: This cross-sectional study was conducted at Ghaem Hospital, Mashhad, in 2023. Patients with histopathologically confirmed primary brain tumors (gliomas and meningiomas) who had previously received treatment and presented with suspected tumor recurrence based on imaging findings were included. After injection of ^99mTc-HYNIC-Octreotide, whole-body SPECT/CT imaging of the head and other suspicious areas was performed. Two nuclear medicine specialists independently reviewed scans. Radiopharmaceutical uptake was assessed qualitatively by comparing absorption in lesions to liver and splenic uptake, with scoring based on the Krenning score. The uptake in lesions (target) and their corresponding mirrored normal brain regions (non-target) was calculated using ROI measurements.

Results: Out of 24 patients, scans from 18 (mean age: 51.39±12.25 years; range: 35-74) were analyzed due to technical issues and missing images. Of these, 10 (55.6%) were women. Somatostatin receptor expression was observed in all lesions. Meningioma had significantly higher receptor expression compared to gliomas (P=.003). Maximum and target-to-non-target uptake differences were significantly greater in meningioma than in astrocytoma (P=.047, P=.044) and glioblastomas (P=.025, P=.026). Gliomas, including astrocytoma and glioblastomas, consistently showed low receptor expression, and no significant differences in receptor expression were observed between astrocytoma and glioblastomas.

Conclusion: This study demonstrates that ^99mTc-HYNIC-octreotide SPECT/CT imaging is an effective method for detecting somatostatin receptor expression in brain tumors, offering a low-cost and accessible alternative to more enhanced imaging techniques, both meningioma and glial tumors express somatostatin receptors, but receptor expression is significantly higher in meningioma.

Introduction: In response to the increasing demand for radioguided procedures, the integration of the Nursing Care Assistants (NCA) profile was proposed as support professionals in the preoperative marking of breast cancer (BC) patients using I-125 seeds.

Objectives: To analyze the clinical impact and professional development resulting from the integration of NCA into these procedures, assessing the operational efficiency of the Radioguided Surgery Team (RGST) and the training process that enabled them to assume new competencies.

Materials and methods: A four-phase theoretical-practical training program was implemented (theoretical instruction, practical mentoring, clinical simulation, and supervised autonomous practice), aimed at training NCA to assist in the localization and marking of non-palpable lesions and metastatic axillary lymph nodes using I-125 seeds. After completing the training, their impact was evaluated through a comparative analysis of RGST activity in 2023 and 2024.

Results: During the study period, NCA autonomously performed 116 marking procedures with I-125 seeds without incidents, accounting for 11.8% of total procedures in 2023 (32/270) and 23% in 2024 (84/366). Operational support was required on 21 working days in 2023 (8.5%) and 49 days in 2024 (19.6%), indicating a significant increase in their involvement.

Conclusions: The incorporation of the NCA profile into radioguided marking procedures has proven to be an effective strategy for optimizing healthcare resources, enhancing the operational efficiency of the RGST, and promoting the professional development of this role within highly specialized clinical settings.

Purpose: The aim of this study was to evaluate the utility of radiomics based on [¹⁸F]FDG PET/CT imaging for the prediction of histological differentiation grade in patients with non-small cell lung cancer (NSCLC) of either adenocarcinoma or squamous cell carcinoma subtype.

Materials and methods: A single-center retrospective observational study was conducted, including 150 patients with histologically confirmed NSCLC who underwent [¹⁸F]FDG PET/CT imaging prior to complete surgical resection of the tumor. Patients were excluded if they showed no significant FDG uptake, lacked differentiation data, or had insufficient tumor volume. Image segmentation and feature extraction were performed using LIFEx software, obtaining both textural and morphological features. Predictive variables were selected using classical statistical techniques and LASSO regression, and model performance was evaluated using ROC curve analysis.

Results: Among the 150 patients included, 25 had well-differentiated tumors, 88 moderately differentiated, and 37 had poorly differentiated. Comparison between well-differentiated tumors and those with moderate or poor differentiation revealed statistically significant differences in several radiomic features. The LASSO model identified seven variables with high discriminative power. The model achieved a sensitivity of 76%, specificity of 99.2%, positive predictive value of 95%, negative predictive value of 95.4%, and an overall accuracy of 95.3%.

Conclusions: Radiomic features extracted from [¹⁸F]FDG PET/CT images can predict tumor differentiation grade in NSCLC with high specificity. This non-invasive approach may serve as a valuable adjunct to histopathological evaluation, potentially aiding clinical decision-making.