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Objectives: This study aimed to compare the metabolic parameters obtained from 18 fluorine-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) and gallium-68 ( 68 Ga)-prostate-specific membrane antigen (PSMA) PET/CT and investigate the relationship between serum alpha-fetoprotein and PET scan parameters in patients with hepatocellular carcinoma., Methods: Fourteen patients were recruited after dynamic magnetic resonance imaging (MRI) of the upper abdomen, and 18 F-FDG and 68 Ga-PSMA PET/CT imaging studies were conducted. Regions of interest (ROIs) were drawn from lesion-free liver tissue, abdominal aorta (A), and right medial gluteal muscle (G) for the background activity. Maximum standard uptake value (SUV max ) of these regions were compared with the SUV max of primary tumor (T)., Results: On visual assessment, five patients (36%) experienced low 18 F-FDG uptake in the primary lesion, three patients (21%) experienced moderate uptake, and six patients (43%) experienced high uptake. However, only one patient (7%) showed low 68 Ga-PSMA uptake, two patients (14%) showed moderate uptake, and 11 patients (79%) showed high uptake. Four patients with a low 18 F-FDG uptake showed high 68 Ga-PSMA uptake, while one patient exhibited low uptake with both 18 F-FDG and 68 Ga-PSMA. The number of lesions on 68 Ga-PSMA PET/CT and MRI was significantly higher than 18 F-FDG PET/CT (p=0.042 and 0.026, respectively). T/A and T/G values were significantly higher in 68 Ga-PSMA than 18 F-FDG (p=0.002 and 0.002, respectively)., Conclusion: 68 Ga-PSMA PET/CT is superior to 18 F-FDG PET/CT in the staging of hepatocellular carcinoma. High 68 Ga-PSMA uptake could be promising for PSMA-targeted radionuclide treatments.

Objective: Our aim is to evaluate if different metabolic parameters obtained by 18 F-FDG PET/CT and diffusion weighted magnetic resonance imaging (DW-MRI) can aid in neoadjuvant radiochemotherapy (RCT) response assessment in locally advanced rectal cancer (LARC) patients., Methods: Out of 20 LARC patients, who were planned to receive neoadjuvant RCT, 19 were included in this prospective study. Patients had 18 F-FDG PET/CT and DW-MRI at initial staging, interim (2 weeks after onset of RCT) and after completion of RCT (post-therapy). Standardized uptake value (SUV) parameters (SUVmax, SUVmean, SUVpeak, SULpeak), metabolic tumor volume (MTV) and tumor lesion glycolysis (TLG) detected on PET images and apparent diffusion coefficient (ADC) values (for b=400 and b=1000s/mm 2 ) obtained from DW-MRI were recorded. Postoperative tumor regression grade (TRG) was used as gold-standard, except for 2 patients who were under complete remission with non-operative management 19 months post-therapy and scored as responders., Results: On interim PET/CT, no significant difference was found among PET parameters between responders and non-responders, whereas post-therapy SUVmax, SUVpeak, MTV, SULpeak, TLG (P=0.02, P=0.014, P=0.025, P=0.007, P=0.02, respectively) and initial MTV (P=0.034) were significantly lower in responders. ADC response index (RI) was higher in responders (interim P=0.026; post-therapy: P=0.018) and ROC analysis revealed that a threshold of ADC RI>41.6% for interim MRI and >44.6% for post-therapy MRI had sensitivity and specificity of 75.0% and 90.9%, respectively., Conclusions: While interim 18 F-FDG PET/CT failed to predict therapy response during RCT, post-therapy PET could accurately differentiate responders. DW-MRI was found to be more promising in interim detection of RCT response., (Copyright © 2020 Sociedad Española de Medicina Nuclear e Imagen Molecular. Publicado por Elsevier España, S.L.U. All rights reserved.)

Purpose: Lymphovascular invasion (LVI) and perineural invasion (PNI) are associated with poor prognosis in gastric cancers. In this work, we aimed to investigate the potential role of computed tomography (CT) texture analysis in predicting LVI and PNI in patients with tubular gastric adenocarcinoma (GAC) using a machine learning (ML) approach., Methods: Sixty-eight patients who underwent total gastrectomy with curative (R0) resection and D2-lymphadenectomy were included in this retrospective study. Texture features were extracted from the portal venous phase CT images. Dimension reduction was first done with a reproducibility analysis by two radiologists. Then, a feature selection algorithm was used to further reduce the high-dimensionality of the radiomic data. Training and test splits were created with 100 random samplings. ML-based classifications were done using adaptive boosting, k-nearest neighbors, Naive Bayes, neural network, random forest, stochastic gradient descent, support vector machine, and decision tree. Predictive performance of the ML algorithms was mainly evaluated using the mean area under the curve (AUC) metric., Results: Among 271 texture features, 150 features had excellent reproducibility, which were included in the further feature selection process. Dimension reduction steps yielded five texture features for LVI and five for PNI. Considering all eight ML algorithms, mean AUC and accuracy ranges for predicting LVI were 0.777-0.894 and 76%-81.5%, respectively. For predicting PNI, mean AUC and accuracy ranges were 0.482-0.754 and 54%-68.2%, respectively. The best performances for predicting LVI and PNI were achieved with the random forest and Naive Bayes algorithms, respectively., Conclusion: ML-based CT texture analysis has a potential for predicting LVI and PNI of the tubular GACs. Overall, the method was more successful in predicting LVI than PNI.

OBJECTIVE Analyze the over expression of neural precursor cell expressed developmentally down-regulated protein 9 (NEDD-9) deregulated associated with a poor prognosis in various carcinomas. Our objective was to investigate the relationship between the levels of NEDD-9, CA 15-3, and CEA and PET (SUVmax, MTV40, TLG40) with the clinical parameters of patients with breast cancer (BC). METHODS One hundred and eleven patients (82 BC patients who underwent 18F-FDG PET/CT and 29 healthy controls) were evaluated. SUVmax, MTV, and TLG of the primary tumor were compared with the molecular and histopathological subtypes. 18F-FDG, MTV, and TLG were evaluated based on the clinical data, i.e., nodal involvement, distant metastasis, ER and PR status, Ki-67, serum levels of NEDD-9, CA15-3, and CEA. We compared the NEDD-9 in the BC and healthy control groups. RESULTS The mean ± SD of SUVmax in the 82 patients was 13.0 ± 8.6. A statistically significant relationship (p = 0.022) was found between the molecular subtypes and 18F-FDG uptake. The relationship between 18F-FDG uptake and TLG measured in patients <50 years, ER-PR negativity, and HER2 positivity were statistically significant (p=0.015, 0.007, 0.046, and 0.001, respectively). MTV40, TLG40, and CA 15-3 in metastatic patients were statistically significant (p=0.004, 0.005, and 0.003, respectively). NEDD-9 in the BC group was significantly higher than in the healthy group (p=0.017). There was a positive correlation between SUVmax and Ki67 and CA 15-3; MTV40 and CEA; CA 15-3, CEA, SUVmax, and MTV40; a negative correlation was found between CEA, TLG40, and age. CONCLUSION The use of SUVmax, MTV40, and TLG40 parameters with NEDD-9 and tumor markers has been shown to provide a high diagnostic, predictive, and prognostic value for the management of BC. This is considered to be the basis of interventions focused on the treatment objectives related to NEDD-9.

Objective: Prognostic effect of KRAS mutation and side of tumor in colorectal cancer is a highly controversial subject. Therefore, we evaluated the association between FDG uptake pattern in 18 F-fluoro-2-deoxy-glucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) imaging and KRAS mutation and tumor localization in patients with a diagnosis of colon cancer and assessed the effects of these three factors on prognosis and survival., Methods: Eighty-three patients with colorectal cancer were retrospectively included in this study. 18 F-FDG PET/CT study was performed for pretreatment staging. The maximum standardized uptake value (SUV max ) of the primary tumor and survival data of patients were compared between groups. KRAS mutations were detected with the help of real-time Polymerase Chain Reaction technique through genomic DNA extracted from paraffin-embedded tumor tissue blocks. Tumor lesions with potential KRAS mutations were classified as mutant KRAS and wild type., Results: Twenty five patients were female while 58 were male. The mean age of the patients was 59.8±11.3 years. Mean follow-up was 35.5±18.9 months. Primary tumor was localized in the left colon in 83.1% of patients and in the right colon in 16.9%. KRAS mutation was detected in 54.2% (n=45) of patients. Mean SUV max of patients with primary tumor was estimated to be 21.1±9.1 (range= 6.0-47.5). Mean tumor SUV max of patients with a KRAS mutation (24.0±9.0) was found to be significantly higher than those without KRAS mutation (17.7±8.2) (p=0.001). Mean survival was significantly shorter in patients with locoregional nodal metastasis than in patients without locoregional nodal metastasis as well as in patients with distant nodal metastasis than in patients without distant nodal metastasis and in patients with organ metastasis in initial PET/CT than in patients without organ metastasis. Also, mean survival was nearly statistically-significantly shorter in patients with tumors located in left colon (34.2±19.4) than in right colon (43.2±14.6) (p=0.059). However, we found no significant impact of KRAS mutation on survival., Conclusion: In our study, we found that tumor localization had no significant effect on prognosis in patients with colon cancer. On the other hand, FDG uptake was observed to be higher in the presence of KRAS mutation and it was concluded that coexistence of KRAS mutation with higher SUV max is a negative prognostic factor.

Background/aims: Gallbladder Carcinoma (GBC) is the most common and aggressive tumor of the biliary tract. Patients are typically diagnosed during advanced stages, and the mean overall survival is short. In our study, we aimed to demonstrate the uptake patterns of 18F-FDG PET/CT in GBC, as well as its association with survival and diagnostic value during the initial stage., Materials and Methods: Overall, 17 patients with GBC were retrospectively included in the study. 18F-FDG PET/CT study was performed for pretreatment staging. Two different standardized uptake values (SUVmax and SUVmean), metabolic tumor volume 40% (MTV40), and tumor lesion glycolysis (TLG) of the primary tumors were compared between the clinical and histopathological groups., Results: Of the 17 patients, 11 were women (64.7%), and 6 (35.3%) were men. The mean age of the patients was 69.7±8.8 years. 18F-FDG uptake was detected in all lesions. Mean SUVmax was calculated to be 15.4±13.7 (median=10.6, range=3.4-46.8). All distant metastases (52.9%) were detected in the liver. Semiquantitative metabolic parameters (SUVmax and SUVmean, MTV40, and TLG) obtained from patients with distant metastasis were not significantly higher than those without distant metastasis. Similar results were obtained in patients with and without nodal metastasis. No statistically significant intergroup difference was observed regarding metabolic parameters. However, a statistically significant negative correlation was observed between the patient's age and the SUVmax of the primary lesion and metastatic lymph nodes (r=-0.564, p=0.018). During 10.7±10.4 months of mean follow-up, the mean survival of patients with distant metastases (6.1±11.0 months) was significantly shorter than that of patients with no organ metastases (15.8±7.1 months)., Conclusion: In our study, distant metastases and age were observed to be crucial prognostic factors in patients with gallbladder carcinoma (GBC). In addition, we believe that 18F-FDG PET/CT imaging will help to stage the GBC, detect nodal and distant metastasis, and evaluate the metabolic state of gallbladder lesions.

Purpose: Peritoneal dialysis patients have particular risks with respect to their lipid status and hyperinsulinemia. The aim of this study was to investigate the relation between insulin resistance and the type of the peritoneal dialysis solution., Materials: 41 randomly selected non-diabetic patient cohort who were already under treatment with continuous ambulatory peritoneal dialysis (CAPD) and 10 healthy controls participated in the study. 24 of the 41 patients were using 3 standard 1.36% glucose solutions during the day and 1 hypertonic solution with 2.27% glucose dwell during the night (glucose group: mean age 45.54 +/- 16.67 years and median CAPD duration 16.5 months). The remaining 17 patients were using 3 standard 1.36% glucose solutions during the day and 1 icodextrin dwell during the night for 8-10 hours (icodextrin group: mean age 47.47 +/- 13.15 years, median duration of icodextrin use 6 months (range 2-20 months), and median CAPD duration 30 months). Insulin resistance (IR) was calculated according to the homeostasis model assesment (HOMA) formula: HOMA-IR = fasting glucose (mmol/l) x fasting insulin (microU/1/22.5. The HOMA cutoff point for diagnosis of insulin resistance was established with receiver-operating characteristic (ROC) curves. The patients were called HOMA-IR(+) if their HOMA scores were higher than cutoff value., Results: There were no significant differences between age, BMI, triglyceride, total and high-density lipoprotein (HDL) cholesterol, iron and ferritin, alanine aminotransferase, fibrinogen, intact parathyroid hormone, magnesium, hemoglobin and hematocrit levels of the 2 groups. The mean glucose levels of the groups were not different but fasting insulin levels and HOMA scores of the icodextrin group were significantly lower than the glucose group (10.15 +/- 6.87 vs. 18.11 +/- 13.15, p = 0.028, and 2.28 +/- 1.67 vs. 4.26 +/- 3.27, p = 0.027, respectively). The ratio of patients with low HOMA scores (cutoff = 2.511) were significantly higher in the icodextrin group than in the glucose group (71% vs 38%, p = 0.037). Other than fasting insulin and glucose levels, significantly positive correlation was found between HOMA score and BMI in both groups. With regression analysis, we found that the main parameters effecting HOMA score were BMI (p = 0.008) and triglyceride (p = 0.029) in the glucose group, but no parameters were found to affect HOMA score in icodextrin group., Conclusion: These results suggest that insulin resistance is reduced in peritoneal dialysis patients using icodextrin-based dialysis fluid instead of glucose-based dialysis fluid.

Aim: To investigate the effects of intravenous (i.v.) iron replacement on hepatic functions of hepatitis C virus (HCV)-positive haemodialysis patients., Methods: The present retrospective study included 89 HCV-positive and 57 HCV-negative haemodialysis patients. Alanine aminotransferase (ALT) levels were accepted as sustained high if the last three values were >/=20 U/L. All patients and the HCV-positive group were dichotomised into subgroups by the median for dialysis duration, the amounts of i.v. iron administered per year and totally., Results: Sustained high levels of ALT were significantly more frequent in the HCV-positive group (P < 0.001). In HCV-positive patients, the subgroup with ALT levels >/=20 U/L had significantly higher serum iron levels and mean amounts of i.v. iron administered per year and totally (P < 0.001) and the subgroup with the high mean total amount of i.v. iron had significantly higher serum ALT and iron levels (P < 0.001). Significant positive correlations were found in HCV-positive patients between ALT and serum iron levels (P < 0.001), as well as between ALT both with the mean amounts of i.v. iron administered per year (P = 0006) and totally (P = 0.015). Regression analysis showed that the main parameters effecting ALT were the serum iron level (P < 0.0001) and the mean amount of parenteral iron administered per year (P = 0.032)., Conclusion: We conclude that parenteral iron replacement might contribute to hepatocellular injury in HCV-positive haemodialysis patients.