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Öğe 18F-FDG PET/CT parameters for prediction of response to neoadjuvant therapy and prognosis in rectal cancer(Wolters Kluwer Health, 2023) Ebinç, Senar; Güzel, Yunus; Oruç, Zeynep; Kömek, Halil; Kalkan, Ziya; Can, Canan; Taşdemir, Bekir; Urakçı, Zuhat; Kaplan, Muhammet Ali; Küçüköner, Mehmet; Işıkdoğan, AbdurrahmanObjective This study aims to investigate the role of F-18 fluorodeoxyglucose PET/computed tomography (18F-FDG PET/CT) parameters in the prediction of treatment response and the prognosis in locally advanced rectal cancer. Methods We investigated the relationship of 18F-FDG PET/CT parameters [rectal metabolic tumor volume (MTV), rectal total lesion glycolysis (TLG), rectal standard uptake value (SUV) max, rectal highest peak SUV, lymph node MTV, lymph node TLG, lymph node highest peak SUV] with the pathological response and disease-free survival (DFS) in 60 patients who received neoadjuvant therapy for a diagnosis of locally advanced rectal cancer. Patients with a total score of 0 were assigned to the low-risk group, patients with a score of 1 were assigned to the intermediate-risk group and patients with a score of 2 were assigned to the high-risk group. Results The multivariate analysis revealed that, from baseline PET CT parameters, lymph node highest peak SUV strongly predicted the pathological response at a cutoff value of 2.23. DFS was predicted by the lymph node highest peak SUV at a cutoff value of 3.13 and by the MTV value at a cutoff value of 27 cm3. The risk scoring performed with regard to rectal MTV and lymph node highest peak SUV values determined a median DFS of 19 months in patients with a risk score of 2, whereas the median DFS was not reached in patients with risk scores of 0 and 1 (P < 0.001). Conclusion This study determined that rectal MTV and lymph node highest peak SUV predicted the response to neoadjuvant therapy and DFS.Öğe Comparison of F-18-FDG PET/CT and Ga-68-FAPI-04 PET/CT in the staging and restaging of gastric adenocarcinoma(Lippincott William & Wilkins, 2022) Gündoğan, Cihan; Kömek, Halil; Can, Canan; Yıldırım, Özgen Ahmet; Kaplan, İhsan; Erdur, Erkan; Poyraz, Kerem; Güzel, Yunus; Oruç, Zeynep; Çakabay, BahriObjective In this study, we aimed to evaluate the diagnostic sensitivities of Ga-68-FAPI-04 PET/CT and F-18-FDG PET/CT in the primary tumor, and nodal, peritoneal and distant organ metastases of primary and recurrent gastric adenocarcinoma (GAc) with patient and lesion-based comparison. Materials and method Twenty-one patients with histopathologically proven newly diagnosed or recurrent GAc who underwent F-18-FDG and Ga-68-FAPI-04 imaging were included in the study. Both imaging techniques were evaluated visually according to the intensity of organ-based uptake. SUVmax and tumor-to-background ratio (TBR) values obtained from primary tumor/relapse and metastatic organs were compared statistically. Results Ga-68-FAPI-04 uptake was positive in all 15 newly diagnosed patients, while two patients among them who had mucinous and signet ring cell carcinoma did not exhibit F-18-FDG uptake. The sensitivity and specificity of Ga-68-FAPI-04 PET/CT in detecting primary gastric were 100%, while the sensitivity and specificity of F-18-FDG were 86.6 and 100%, respectively. Ga-68-FAPI-04 imaging revealed diffuse stomach uptake in seven patients, while F-18-FDG could only show two of them. The sensitivity and specificity of in-patient-based detection of lymph node metastases were 100 and 95.2%, respectively, while these values were 71.4 and 93.7%, respectively, for F-18-FDG. For peritoneal involvement Ga-68-FAPI-04 had a sensitivity and specificity of 100%, whereas F-18-FDG had a sensitivity of 40% and a specificity of 100%. Conclusion Ga-68-FAPI-04 PET/CT is an imaging modality with the potential of yielding more sensitive and specific findings F-18-FDG PET/CT. This modality may help avoid invasive diagnostic procedures that may be frequently required in GAc.Öğe Efficacy of Ga-68-PSMA PET/CT-derived whole-body volumetric parameters in predicting response to second-generation androgen receptor axis-targeted therapy, and the prognosis in metastatic hormone-refractory prostate cancer patients(Lippincott William & Wilkins, 2021) Oruç, Zeynep; Güzel, Yunus; Ebinç, Senar; Kömek, Halil; Küçüköner, Mehmet; Kaplan, Muhammet Ali; Oruç, İdris; Urakçı, Zuhat; Işıkdoğan, AbdurrahmanIntroduction The present study investigates the role of Ga-68-PSMA PET/CT-derived whole-body metabolic and volumetric parameters in the prediction of treatment response and prognosis among metastatic hormone-refractory prostate cancer patients undergoing second-generation androgen receptor axis-targeted therapy (abiraterone or enzalutamide). Materials and methods This retrospective study included 44 metastatic hormone-refractory prostate cancer patients undergoing Ga-68-PSMA PET/CT, including 29 enzalutamide-treated and 15 abiraterone-treated patients. Results Of the 44 patients included in the study, 29 received enzalutamide and 15 received abiraterone. During treatment, the changes in PET parameters were correlated with the PSA (biochemical) response. More specifically, a positive correlation was noted between PSA response and percent change in TLP (Delta TLP) response, and there was concordance between the results (r = 0.652, k = 0.42, P < 0.001). Baseline PSA (P =0.05), high MTVw (P = 0.005), the increase in Delta PSA (P = 0.036), Delta TLP (P = 0.039) and percent change in MTV (Delta MTV) (P = 0.049) values were identified as factors associated with mortality risk.Multivariate analysis showed that PSA1 [odds ratio (OR): 1.005, 95% confidence interval (CI) 1.002-1.008, P = 0.004], Delta PSA (OR: 14.7, 95% CI 1.50-143.7, P = 0.02) and MTVw1 (OR: 11.4, 95% CI 1.11-116, 6, P = 0.04) were independent prognostic factors associated with mortality risk. Conclusion A statistically significant concordance and correlation was noted between Ga-68-PSMA PET/CT-derived whole-body metabolic parameters (Delta TLP and Delta MTV) and Delta PSA. In addition, the baseline PSA, Delta PSA, Delta TLP, Delta MTV and TMTV were identified as predictive factors for mortality risk.Öğe Ga-68-FAPI-04 PET/CT, a new step in breast cancer imaging: a comparative pilot study with the F-18-FDG PET/CT(Springer, 2021) Kömek, Halil; Can, Canan; Güzel, Yunus; Oruç, Zeynep; Gündoğan, Cihan; Yıldırım, Özgen Ahmet; Kaplan, İhsan; Erdur, Erkan; Yıldırım, Mehmet Serdar; Cakabay, BahriAbstract Aim We aimed to compare the roles of Ga-68-FAPI-04 PET/CT and F-18-FDG PET/CT in the evaluation of primary tumor and metastases in primary and recurrent breast cancer. Materials and method Twenty female patients with histopathologically confirmed primary and recurrent breast cancer were included in the prospective study. All patients underwent FDG and FAPI PET/CT imaging in the same week. The number of primary and metastatic lesions, SUVmax values, and tumor-to-background ratios (TBR) were recorded from both scans. Data obtained were statistically compared. Results FAPI PET/CT was superior to FDG in detecting breast lesions, as well as hepatic, bone, lymph node, and cerebral metastases in terms of patient- and lesion-based assessments. The sensitivity and specificity of FAPI in detecting primary breast lesions were 100% and 95.6%, respectively, while the sensitivity and specificity of FDG were 78.2% and 100%, respectively. The SUVmax values of primary breast tumors, lymph nodes, lung metastases, and bone metastases were significantly higher on FAPI imaging than FDG imaging (p < 0.05). However, SUVmax values of hepatic metastases did not exhibit a statistically significant difference between two imaging techniques (p > 0.05). Also, FAPI imaging yielded significantly higher TBR in breast lesions as well as hepatic, bone, brain and lung metastases compared to FDG (p < 0.05). Conclusion (68) Ga-FAPI-04 PET/CT is superior to F-18-FDG PET/CT in detecting the primary tumor in patients with breast cancer with its high sensitivity, high SUVmax, and high TBR. (68) Ga-FAPI-04 PET/CT is also superior to F-18-FDG PET/CT in detecting lymph node, hepatic, bone, and cerebral metastases because it has lower background activity and higher uptake in subcentimetric lesions.Öğe Is there a relationship between the liver SUVmax values in FDG-PET/CT imaging and non-alcoholic fatty liver disease score?(2021) Yalçın, Kendal; Güzel, Fatih; Kaplan, İhsan; Güzel, Yunus; Taşdemir, Bekir; Uyar, Ali; Tuzcu, Şadiye AltunAim: Non-alcoholic fatty liver disease is one of the most common causes of liver disease worldwide with an estimated prevalence of 20%–30% in adult population. Following the widespread utilization of PET in the evaluation of malignant diseases, F-18 FDG have also been reported to be used in non-malignant processes. The aim of this study is to elucidate whether the FDG SUVmax values determined by PET/CT in different adipose tissue samples and the liver change according to NAFLD score. During our desktop research we did not find any published article therefore, it is the first study in this field. Materials and Method: A total of 230 patients who applied to Dicle University Faculty of Medicine, Department of Nuclear Medicine between March and April 2020 and who have been conducted FDG PET/CT for diagnosis, staging, restaging and evaluation of response to treatment were included in the study. Patients were divided into three groups according to their NAFLD score as patients with fibrosis score <-1,455 (the group in which severe fibrosis was excluded) as group-1, and those with NAFLD score between -1.455-0.676 (inter-mediate score) as group-2. and patients with a NAFLD score >0.676 (severe fibrosis group) group-3. Results: Liver SUVmax levels were found to be significantly higher in group-3 than group-1. No significant difference was observed between group-2 and group-3. SUVmax levels measured from supracalvicular region, posterior scapular region and mesentery region were not different from each other in all three groups. Glucose-corrected liver SUVglu levels were found to be significantly lower in group-1 than group-3 (p=0.001). In terms of liver SUVglu levels, group-1 and group-2 and group-2 and group-3 did not differ statistically from each other. Supracalvicular SUVglu, posterior scapular SUVglu and mesenteric SUVglu groups were not different from each other. Conclusions: The most important result of this study could be elaborated with increased FDG uptake in NAFLD. Liver FDG uptake increases as the severity of NAFLD increases as demonstrated by the NAFLD score.Öğe The relationship between inflammation markers, positron emission tomography/ /computed tomography parameters and disease prognosis in advanced non-small-cell lung cancer patients(Via Medica, 2024) Pirinççi, Esra; Oruç, Zeynep; Ebinç, Senar; Güzel, Yunus; Kömek, Halil; Küçüköner, Mehmet; Urakçı, Zuhat; Taşdemir, Bekir; Işıkdoǧan, Abdurrahman; Kaplan, Muhammet Ali; 0009-0008-5307-8342; 0000-0002-7931-2941; 0000-0002-0878-6525; 0000-0002-8555-0460; 0000-0001-8168-136X; 0000-0001-7336-871X; 0000-0003-3878-988X; 0000-0002-7787-0341; 0000-0002-7451-7286; 0000-0003-0882-0524Introduction. Inflammation is known to be related to the development, spread, prognosis, and treatment response in cancer patients. Our study aimed to evaluate the correlation between inflammation indices and positron emission tomography-computed tomography (PET/CT) parameters and investigate their relationship with progression-free survival (PFS) and overall survival (OS) in patients diagnosed with stage-IV non -small cell lung cancer (NSCLC). Material and methods. Demographic, clinicopathological, laboratory, and PET/CT data of 179 patients diagnosed with stage-IV NSCLC who presented to the Oncology Department of Dicle University, Faculty of Medicine between 2010-2020 were retrieved from patient files and the hospital database system. Results. The median age at diagnosis was 64 (27-87) years. All patients included in the study had NSCLC: 72.6% had adenocarcinoma, 21.2% had squamous cell carcinoma, and 6.1% had other histological types. Of the 78 patients who were subjected to molecular analysis, 26 (33.3%) were EGFR-mutation positive. During the 10-month median follow-up, median first -line PFS was 6 months (95% CI 5.00-6.99), and median OS was 10 months (95% CI 7.8-12.1). The multivariate analysis performed for first -line PFS determined hemoglobin (HR = 1.01; 95% CI 1.003-1.02; p = 0.005) and PET total lesion glycolysis (TLG) (HR = 1.002; 95% CI 1.001-1.003; p = 0.003) values as independent prognostic factors. The multivariate analysis for OS determined positive EGFR mutation status (HR = 0.385; 95% CI 0.213-0.696; p = 0,014) and performance status (HR = 1.88; 95% CI 1.092-3.238; p = 0,008) as independent prognostic factors. Conclusions. Our study determined the hemoglobin level and PET TLG from PET/CT parameters to be independent prognostic factors for PFS, and performance status and EGFR mutation positivity to be independent prognostic factors for OS.Öğe Superiority of 68 Ga-Trivehexin PET/CT Over 18 F-FDG PET/CT in the Evaluation of Lymph Nodes in Patients With Breast Cancer(Lippincott Williams and Wilkins, 2024) Kömek, Halil; Güzel, Yunus; Kaplan, İhsan; Yilmaz, Ece Eşsiz; Can, CananA patient with left upper quadrant breast cancer who had 18F-FDG PET/CT imaging underwent 68Ga-Trivehexin PET/CT. 68Ga-Trivehexin PET/ CT showed higher radiotracer accumulation in the primary tumor, left internal mammary lymph nodes, and axillary lymph nodes compared with 18F-FDG PET/CT. However, Trivehexin uptake was not observed in FDG-positive lymph nodes in the mediastinum and left hilar region. Benign cytological findings were noted in the biopsy of the subcarinal lymph node. This case demonstrates that the use of 68Ga-Trivehexin PET/CT in suspicious lymph nodes in areas difficult to biopsy in breast cancer cases can contribute to accurate staging. Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.Öğe The relationship between 68Ga-PSMA uptake and Gleason Score and PSA levels in patients with prostate cancer(MediHealth Academy Yayıncılık, 2021) Altuntuzcu, Şadiye; Taşdemir, Bekir; Kaplan, İhsan; Uyar, Ali; Güzel, Fatih; Güzel, Yunus; Dağgülli, MansurAim: PSMA expression has been observed in increased levels in patients with high Gleason scores. Current information on Ga-68 PSMA PET/CT shows that primary staging with PET/CT is important in patients with high-risk PC. Ga-68 PSMA PET/CT may also have a place in patients with intermediate risk PC, but only a few data are available at present. In this study, we aimed to elucidate the relationship between PSMA expression value in the prostate gland, total PSA levels and GS in patients diagnosed with prostate cancer. Material and Method: A total of 98 patients who were pathologically diagnosed with prostate cancer that did not receive any treatment and underwent Ga-68 PSMA PET/CT imaging for staging were included in the study. Findings detected in Ga-68 PSMA PET/CT imaging were categorized as prostate, lymph node, bone, and visceral organ. The focal increased PSMA expression values ??observed in the prostate gland were recorded as SUVmax. The patients were divided into two separate groups according to their GS score (GS>7 and GS?7). Correlations between prostate PSMA SUVmax, GS score and total PSA scores were investigated. Results: PSMA SUVmax levels of the group with a Gleason score of >7 were found to be significantly higher than the group with a Gleason score of ?7 (p=0.03). The rates of lymph node metastasis, bone metastasis and visceral organ metastases were found to be significantly higher in the group with a Gleason score >7 compared to the group with a Gleason score ?7. A positive correlation was observed between PSMA SUVmax and Total PSA (r=0.260, p=0.01). A positive correlation was observed between PSMA SUVmax and Gleason score (r=0.260, p=0.01). A positive correlation was observed between total PSA and Gleason score (r=0.320, p=0.001). Conclusion: In conclusion, PSMA SUVmax and Total PSA levels were higher in the group with high Gleason score. There is a positive correlation between PSMA SUVmax and total PSA. Clinicians should be careful in this regard, as the possibility of metastasis will be high in groups with high Gleason scores.