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OBJECTIVE The aim of this study was to evaluate the relationship between volumetric parameters calculated using semiautomatic quantification of lesions detected in 68Ga-labeled prostate-specific membrane antigen PET-computed tomography (68Ga-PSMA PET/CT) and clinical characteristics in prostate cancer (PCa) patients with biochemical recurrence. METHODS A total of 85 consecutive PCa patients with biochemical recurrence who underwent 68Ga-PSMA PET/CT at our institution from January 2019 to March 2020 were retrospectively assessed. 68Ga-PSMA PET/CT-derived volumetric parameters, including whole-body PSMA tumor volume (wbPSMA-TV) and whole-body total lesion PSMA (wbTL-PSMA), as well as the established maximum and mean standardized uptake value (SUVmax and SUVmean), were calculated for each patient. All PET-derived parameters were analyzed for correlation with prostate-specific antigen (PSA) levels and for association with Gleason scores. RESULTS Eighty-five patients with a mean age of 68.9 ± 7.8 years (range, 47-83 years) and a mean PSA level of 40.9 ± 92.1 ng/ml (range, 0.2-533.2 ng/ml) were analyzed. Volumetric parameters, that is, wbPSMA-TV and wbTL-PSMA, demonstrated a statistically significant correlation with PSA levels (r = 0.403 and r = 0.556, respectively, all at P < 0.001) and only the means of wbTL-PSMA were significantly different between the Gleason score groups (P < 0.05). CONCLUSIONS The results of our study indicate that 68Ga-PSMA PET/CT might be a valuable tool for the detection and follow-up of recurrence in PCa patients. 68Ga-PSMA PET/CT-derived quantitative volumetric parameters demonstrated a highly significant correlation with changes in PSA levels. Larger prospective studies are needed to help reveal the full potential of parameters such as PSMA-TV and TL-PSMA derived from PET imaging with 68Ga-PSMA.

To develop a nomogram based on commonly used clinical data for predicting the likelihood of metastasis in gallium-68 prostate-specific membrane antigen PET/computed tomography (Ga-68 PSMA PET/CT) scans of prostate cancer patients with confirmed biochemical recurrence (BCR).One-hundred thirty-five ( n = 135) patients who underwent Ga-68 PSMA PET/CT due to BCR were included in the study. Predictors of metastasis in Ga-68 PSMA PET/CT were determined with multivariable logistic regression analysis. Coefficients derived from the regression model were used to develop a prediction nomogram. The performance of the prediction model was evaluated with receiver operating characteristic analysis. Internal validation was performed with 50 bootstrap resamples, and the nomogram's clinical benefit was assessed with decision curve analysis.Multivariable logistic regression analysis revealed that ISUP group, prostate-specific antigen (PSA) before PET and PSA doubling time were independent predictors of metastasis in Ga-68 PSMA PET/CT. A prediction nomogram was developed according to this model [the area under curve: 0.866; 95% confidence interval (CI), 0.788-0.944]. The best cutoff value of the nomogram-derived likelihood for predicting metastasis was 60%, with a bootstrap-corrected accuracy of 78.8%. An online version of the nomogram was implemented on pro-gram.nzm.co ( https://pro-gram.nzm.co ).The proposed nomogram provides a practical approach for predicting the likelihood of imaging-based metastasis according to Ga-68 PSMA PET/CT in patients with BCR, with results ≥60% being the most accurate cutoff for referring patients to Ga-68 PSMA PET/CT. If validated in a larger cohort, this tool can serve as a guide for the appropriate use of Ga-68 PSMA PET/CT.

Aim Gastric carcinoma is one of the most frequent cancers and leading causes of cancer-related death worldwide. Treatment strategies are planned according to the Tumour-Node-Metastasis (TNM) stage of the disease. However, the prognosis varies substantially even within the same stage. Prognostic nomograms were designed to overcome this diversity. In this study, staging systems and prognostic tools are compared in the context of their ability to predict patients' prognosis. Methods Records of 391 patients operated for gastric cancer from January 2006 to September 2013 were analysed retrospectively. TNM staging system, Metastatic lymph node ratio (LNR), Kattan Prognostic Tool and Prognostic Tool of Italian Research Group on Gastric Cancer (GIRCG) were compared with the patients' survival times by their concordance indices and correlation coefficients. Results A total of 343 patients were included in the study. Concordance indices of the compared staging systems were 0.678 for TNM, 0.601 for GIRCG scale, 0.646 for LNR stage and 0.680 for Kattan scale. Pearson correlation coefficients were 0.404 for TNM staging, 0.314 for GIRCG scale, 0.304 for LNR stage and -0.406 for Kattan scale. Spearman correlation coefficients were 0.383, 0.311, 0.310 and -0.400 respectively. Conclusion Based on these results, Kattan prognostic scale was found to be the most accurate system for predicting mortality. This was followed by TNM staging system.

Objective The aim of this study was to evaluate the accuracy of technetium- 99m-methoxyisobutylisonitrile (Tc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) and ultrasound in preoperative localization of single parathyroid adenomas (PTAs) in patients with primary hyperparathyroidism (pHPT) who would be suitable for minimally invasive parathyroidectomy (MIP). Methods A retrospective study of 143 consecutive patients with biochemical evidence of hyperparathyroidism who underwent preoperative localization of parathyroid lesions using Tc-MIBI SPECT/CT and ultrasound, and proceeded to parathyroid surgery at our institution from January 2013 to January 2018. Of these, 125 had single adenomas and are the subject of this study. The sensitivity, positive predictive value (PPV) and accuracy of the two imaging techniques for the accurately identification and lateralization of PTAs were determined using histopathology as the criterion standard. Results Of 125 PTAs, the correct identification and lateralization were significantly higher by SPECT/CT than ultrasound. SPECT/CT and ultrasound detected lesions with histopathologically proven PTAs in 116 and 95 patients, respectively. The sensitivity, PPV and accuracy were 92.17, 94.64 and 87.60%, respectively, for SPECT/CT and 75.89, 90.43 and 70.25%, respectively, for ultrasound in lateralization analysis. Conclusions The results of our study indicate that Tc-MIBI SPECT/CT is more accurate than ultrasound for the preoperative identification of single PTAs in patients with pHPT who are candidates for MIP.

Purpose We sought to investigate the performance of radiomics analysis on baseline 18F-FDG PET/CT for predicting response to first-line chemotherapy in diffuse large B-cell lymphoma (DLBCL). Material and methods Forty-five patients who received first-line rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy for DLBCL were included in the study. Radiomics features and standard uptake value (SUV)-based measurements were extracted from baseline PET images for a total of 147 lesions. The selection of the most relevant features was made using the recursive feature elimination algorithm. A machine-learning model was trained using the logistic regression classifier with cross-validation to predict treatment response. The independent predictors of incomplete response were evaluated with multivariable regression analysis. Results A total of 14 textural features were selected by the recursive elimination algorithm, achieving a feature-to-lesion ratio of 1:10. The accuracy and area under the receiver operating characteristic curve of the model for predicting incomplete response were 0.87 and 0.81, respectively. Multivariable analysis revealed that SUVmax and gray level co-occurrence matrix dissimilarity were independent predictors of lesions with incomplete response to first-line R-CHOP chemotherapy. Conclusion Increased textural heterogeneity in baseline PET images was found to be associated with incomplete response in DLBCL.

In this study, we aimed to investigate the effects of chronic sleep deprivation on mucociliary clearance, which is the primary defence mechanism of the upper airway tract and nasal mucosal histology. Forty-two Wistar Albino rats (250-300 g), 8 or 12 weeks old, were randomly assigned into three groups as follows. The first sleep-deprivation group consisted of 14 rats (A), another 14 of them were assigned to platform group (B), and the remaining 14 were included to the home cage control group (C). For the two deprivation groups (A and B), the modified multiple platform method (MMPM) was used to induce sleep deprivation for 21 days. Tc-99m MAA rhinoscintigraphy was performed to assess mucociliary clearance and the nasal histopathological changes of the sacrificed rats were also examined. Mucociliary clearance was significantly higher in sleep deprivation (A) and deprivation control (B) groups than the control group (C) (p = .037). The ratio of columnar ciliary was significantly higher in group A and B than in the control group (p = .003). The transitional epithelial ratio in groups A and B was also significantly increased compared with group C (p = .04). The control group's squamous epithelial ratio was increased compared to the sleep-deprived groups (p = .003). There was a significantly increased inflammatory response in the ciliated columnar epithelium in groups A and B compared to group C (p = .02). For the first time in the literature, we demonstrated that chronic sleep deprivation has caused a significant increase in mucociliary clearance speed and in the number of ciliary cells.