Lactate and Lactate Clearance Are Predictive Factors for Mortality in Patients with Extracorporeal Membrane Oxygenation.

INTRODUCTION: Findings of inadequate tissue perfusion might be used to predict the risk of mortality. In this study, we evaluated the effects of lactate and lactate clearance on mortality of patients who had undergone extracorporeal membrane oxygenation (ECMO). METHODS: Patients younger than 18 years old and who needed venoarterial ECMO support after surgery for congenital heart defects, from July 2010 to January 2019, were retrospectively analyzed. Patients successfully weaned from ECMO constituted Group 1, and patients who could not be weaned from ECMO were in Group 2. Postoperative clinics and follow-ups of the groups including mortality and discharge rates were evaluated. RESULTS: There were 1,844 congenital heart surgeries during the study period, and 55 patients that required ECMO support were included in the study. There was no statistically significant difference between the groups regarding demographics and operative variables. The sixth-, 12th-, and 24th-hour lactate levels in Group 1 were statistically significantly lower than those in Group 2 (P=0.046, P=0.024, and P<0.001, respectively). There were statistically significant differences regarding lactate clearance between the groups at the 24th hour (P=0.009). The cutoff point for lactate level was found as ≥ 2.9, with 74.07% sensitivity and 78.57% specificity (P<0.001). The cutoff point for lactate clearance was determined as 69.44%, with 59.26% sensitivity and 78.57% specificity (P=0.003). CONCLUSION: Prognostic predictive factors are important to initiate advanced treatment modalities in patients with ECMO support. In this condition, lactate and lactate clearance might be used as a predictive marker.

68 Ga-PSMA PET/CT Found Lower Respiratory Tract Inflammation Due to Inhaler Use.

ABSTRACT: Prostate-specific membrane antigen (PSMA) is a transmembrane protein physiologically expressed in nonprostatic tissues. Inflammation and infectious diseases could show false-positive PSMA uptake. Herein, we present a 55-year-old patient's findings of inflammation in the lower respiratory tract due to inhaler use in 68 Ga-PSMA PET/CT in a patient with prostate cancer.

Lactate and Lactate Clearance Are Predictive Factors for Mortality in Patients with Extracorporeal Membrane Oxygenation

ABSTRACT Introduction: Findings of inadequate tissue perfusion might be used to predict the risk of mortality. In this study, we evaluated the effects of lactate and lactate clearance on mortality of patients who had undergone extracorporeal membrane oxygenation (ECMO). Methods: Patients younger than 18 years old and who needed venoarterial ECMO support after surgery for congenital heart defects, from July 2010 to January 2019, were retrospectively analyzed. Patients successfully weaned from ECMO constituted Group 1, and patients who could not be weaned from ECMO were in Group 2. Postoperative clinics and follow-ups of the groups including mortality and discharge rates were evaluated. Results: There were 1,844 congenital heart surgeries during the study period, and 55 patients that required ECMO support were included in the study. There was no statistically significant difference between the groups regarding demographics and operative variables. The sixth-, 12th-, and 24th-hour lactate levels in Group 1 were statistically significantly lower than those in Group 2 (P=0.046, P=0.024, and P<0.001, respectively). There were statistically significant differences regarding lactate clearance between the groups at the 24th hour (P=0.009). The cutoff point for lactate level was found as ≥ 2.9, with 74.07% sensitivity and 78.57% specificity (P<0.001). The cutoff point for lactate clearance was determined as 69.44%, with 59.26% sensitivity and 78.57% specificity (P=0.003). Conclusion: Prognostic predictive factors are important to initiate advanced treatment modalities in patients with ECMO support. In this condition, lactate and lactate clearance might be used as a predictive marker.

68 Ga-DOTA-FAPI-04 Imaging of Bilateral Phyllodes Tumor.

ABSTRACT: We present a case of bilateral Phyllodes tumor located in both breasts in a 41-year-old woman who was detected with increased uptake on 68 Ga-FAPI-04 (fibroblast activation protein inhibitor) and 18 F-FDG PET/CT imaging. The tumor filling up the right breast was identified as borderline Phyllodes. The tumor with mild uptake in the left breast was reported as a benign Phyllodes tumor.

68 Ga-FAPI-04 PET/CT in Selected Breast Cancer Patients With Low FDG Affinity : A Head-to-Head Comparative Study.

PURPOSE: In this prospective study, PET findings of 18 F-FDG PET/CT in breast cancer staging were compared with 68 Ga-FAP inhibitor (FAPI) 04 PET/CT findings in selected cases with relatively low 18 F-FDG uptake in the primary tumor or with suspected nodal or distant metastases. PATIENTS AND METHODS: Twenty-four women with a median age of 45 years (range, 36-67 years) who underwent initial staging 18 F-FDG PET/CT for breast cancer underwent 68 Ga-FAPI-04 PET/CT imaging within the same week. SUV max and quantities of primary tumors and locoregional and distant metastatic lesions were recorded from both images, and these data were compared statistically. RESULTS: The histological subtypes of primary tumors were 11 invasive lobular, 8 invasive ductal, and 5 mucinous subtypes. More intense 68 Ga-FAPI-04 uptake (mean, 17.1 ± 7.9; 7.4-38.5) was detected in all primary tumoral lesions compared with 18 F-FDG (mean, 6.3 ± 3.9; 1.5-20.5) ( P = <0.001, Z = 4.107). Additional lesions showing 68 Ga-FAPI-04 uptake in the breast were detected in 29.2% (n = 7) of patients. In 8.3% (n = 2) of the patients, the primary lesion showed only 68 Ga-FAPI-04 uptake. In 68 Ga-FAPI-04 PET/CT, 25% (n = 6) of the patients showed more lymph node involvement and more intense uptake in the ipsilateral axilla. In addition, infraclavicular (level 3) lymph nodes in 4 patients (16.7%), supraclavicular lymph nodes in 1 patient, and internal mammary lymph nodes in 1 patient were detected only on 68 Ga-FAPI-04 PET/CT. In a patient with lung and bone metastases, 68 Ga-FAPI-04 uptake was higher, and the lung nodule showed only 68 Ga-FAPI-04 uptake. CONCLUSIONS: In selected low-FDG-affinity breast cancer patients, 68 Ga-FAPI-04 PET/CT showed the primary tumor with higher sensitivity and higher SUV max values compared with 18 F-FDG PET/CT. In addition, it is believed that this method may contribute to the management of patients' treatment by increasing the nodal stage.

Investigation of the Presence of Integrin Alpha-3 and Beta-1 Receptors on Tumor Tissue, Metastatic Lymph Node and Normal Tissue in Thyroid Cancer.

Objectives: The important roles of integrins in tumor invasion, migration and proliferation are well known. In this study, we investigated the presence of integrin α3 and ß1 receptors in tumor tissue, metastatic lymph node (LN) and normal thyroid tissue of patients diagnosed with thyroid cancer (TCa) and showed the prognostic and diagnostic value of these molecules as well as peptide-receptor. Methods: Sixty-one patients with TCa were included in this study. The presence of integrin α3 and ß1 expression was investigated by immunohistochemical methods from tumor tissue after total thyroidectomy. TNM system was used in tumor staging. The relationship between prognostic properties such as tumor size, LN metastasis, capsular invasion and the presence of integrin α3 and ß1 expression was investigated. Results: Classical type papillary TCa was the most common subtype in our study group with 31.1%. Integrin ß1 was expressed in 4.9% (n=3) of normal tissue, 57.4% (n=35) of tumor tissue and 16.4% (n=10) of metastatic LN; integrin α3 was expressed in 50.8% (n=31) of normal tissue, 67.2% (n=41) of tumor tissue and 9.8% (n=6) metastatic LN. Integrin ß1 expression was observed 21.3% (n=13), integrin α3 in 14.8% (n=9) and integrin α3 and ß1 expression in 36.1% (n=22). Integrin ß1 expression increased statistically significantly in the presence of LN metastasis and capsular invasion (p=0.022, 0.014, respectively). Furthermore, the expression of integrin α3 was found to be statistically significant in primary tumors of patients with LN metastasis (p=0.045). Conclusion: Our study showed a significant increase in integrin α3 and ß1 expression in LN metastasis or thyroid capsule invasion in tumor. Thus, it appears that the demonstration of the presence of integrin α3 and ß1 expression in TCa is not only a prognostic biomarker but also has value as a potential theranostic target with peptide-bound radioactive agents.

Factors affecting the clinical outcomes in pediatric post-cardiotomy patients requiring perioperative peritoneal dialysis.

OBJECTIVE: Fluid overload is associated with increased mortality and morbidity in pediatric cardiac surgery. In the pediatric age group, peritoneal dialysis might improve postoperative outcome with avoiding fluid overload and electrolyte imbalance. It preserves hemodynamic status with the advantage of passive drainage. In this study, we are reporting our results of peritoneal dialysis after cardiac surgery. METHODS: In this retrospective study, we evaluated the patients who underwent pediatric cardiac surgery in our hospital between December 2010 and January 2020. Patients who required peritoneal dialysis during hospitalization period were included in the study. Patients' clinical status and outcomes were evaluated. RESULTS: Peritoneal dialysis was performed to 89 patients during the study period. The age varies from the newborn to 4 years old. The indication of peritoneal dialysis was prophylactic in 68.5% (n=61) and for the treatment in 31.5% (n=28). There were 31 mortalities. The risk factors for the mortality were preoperative lower age, longer cardiopulmonary bypass time, lengthened intubation, lengthened inotropic support, and requirement of extracorporeal membrane oxygenation (p<0.0001). CONCLUSION: Earlier initiation of peritoneal dialysis in pediatric cardiac surgery helps maintain hemodynamic instability by avoiding fluid overload, considering the difficulty in the treatment of electrolyte imbalance and diuresis.

Factors affecting the clinical outcomes in pediatric post-cardiotomy patients requiring perioperative peritoneal dialysis

SUMMARY OBJECTIVE: Fluid overload is associated with increased mortality and morbidity in pediatric cardiac surgery. In the pediatric age group, peritoneal dialysis might improve postoperative outcome with avoiding fluid overload and electrolyte imbalance. It preserves hemodynamic status with the advantage of passive drainage. In this study, we are reporting our results of peritoneal dialysis after cardiac surgery. METHODS: In this retrospective study, we evaluated the patients who underwent pediatric cardiac surgery in our hospital between December 2010 and January 2020. Patients who required peritoneal dialysis during hospitalization period were included in the study. Patients' clinical status and outcomes were evaluated. RESULTS: Peritoneal dialysis was performed to 89 patients during the study period. The age varies from the newborn to 4 years old. The indication of peritoneal dialysis was prophylactic in 68.5% (n=61) and for the treatment in 31.5% (n=28). There were 31 mortalities. The risk factors for the mortality were preoperative lower age, longer cardiopulmonary bypass time, lengthened intubation, lengthened inotropic support, and requirement of extracorporeal membrane oxygenation (p<0.0001). CONCLUSION: Earlier initiation of peritoneal dialysis in pediatric cardiac surgery helps maintain hemodynamic instability by avoiding fluid overload, considering the difficulty in the treatment of electrolyte imbalance and diuresis.

Diffuse Large B-Cell Non-Hodgkin Lymphoma Involving Multiple Different Organs in a Young Adult with 18F-FDG PET/CT.

Extranodal-multiorgan involvement is rarely presented in diffuse large B-cell non-Hodgkin lymphoma. 18Fluorine-fluorodeoxyglucose positron emission tomography/computed tomography findings of a 22-year-old female patient with supra/infra-diaphragmatic nodal and skeletal involvements and thyroid, pancreas, right breast, bilateral renal, and ovarian involvements were presented.

68Ga-PSMA PET/CT Versus 18F-FDG PET/CT for Imaging of Hepatocellular Carcinoma

Objectives: This study aimed to compare the metabolic parameters obtained from 18fluorine-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) and gallium-68 (68Ga)-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 18F-FDG and 68Ga-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 (SUVmax) of these regions were compared with the SUVmax of primary tumor (T). Results: On visual assessment, five patients (36%) experienced low 18F-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 68Ga-PSMA uptake, two patients (14%) showed moderate uptake, and 11 patients (79%) showed high uptake. Four patients with a low 18F-FDG uptake showed high 68Ga-PSMA uptake, while one patient exhibited low uptake with both 18F-FDG and 68Ga-PSMA. The number of lesions on 68Ga-PSMA PET/CT and MRI was significantly higher than 18F-FDG PET/CT (p=0.042 and 0.026, respectively). T/A and T/G values were significantly higher in 68Ga-PSMA than 18F-FDG (p=0.002 and 0.002, respectively). Conclusion: 68Ga-PSMA PET/CT is superior to 18F-FDG PET/CT in the staging of hepatocellular carcinoma. High 68Ga-PSMA uptake could be promising for PSMA-targeted radionuclide treatments.

Systemic Sarcoidosis Induced by Chemotherapy, Mimicking Metastatic Testicular Carcinoma with 18F-FDG PET/CT

A 34-year-old male patient who had left orchiectomy and received three cycles of chemotherapy for testicular mix germ cell carcinoma was referred for 18fluorine-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for complaints of weight loss and fever. PET/CT showed multiple and progressive 18F-FDG uptakes in supra and infra diaphragmatic lymphatic regions, and multiple abnormal 18F-FDG uptakes were noted in the lytic formed skeletal lesions. Clinicians remain in doubt regarding the multiple metastatic lesions without elevated serum tumor marker levels (alpha-fetoprotein, beta-human chorionic gonadotrophin, CA19-9, and carcinoembryonic antigen). Biopsy of the lytic lesion in the iliac bone revealed granulomatous inflammation suggestive of sarcoidosis. Systemic prednisone at 20-40 mg/daily was started. 18F-FDG PET/CT images showed complete metabolic response to prednisone 8 months following the start of treatment.

68Ga PSMA Uptake at Roux-en-Y Eso-jejunostomy Junction Mimicking the Recurrence of Gastric Carcinoma in PET/CT.

A 67-year-old male patient had undergone total gastrectomy and Roux-en-Y eso-jejunostomy 3 years ago for the treatment of tubular adenocarcinoma located at the corpus of the stomach. The patient was diagnosed with Gleason score 8 (4+4) metastatic prostate cancer during the follow-up period and received hormone therapy. Owing to his elevated prostate-specific antigen levels (77 ng/mL), his clinician referred him gallium-68 (68Ga) prostate-specific membrane antigen 11 (PSMA) positron emission tomography/computed tomography (PET/CT) for restaging. PET/CT showed multiple 68Ga PSMA receptor-positive skeletal lesions and linear PSMA activity at the eso-jejunostomy junction. He was then referred to undergo 18fluorine-fluorodeoxyglucose (18F-FDG) PET/CT to screen for gastric carcinoma recurrence. PET/CT images demonstrated no 18F-FDG avid lesion. However, endoscopy and biopsy performed with samples from the eso-jejunostomy junction revealed superficial benign squamous epithelial fragments.

Direct vertebral rotation significantly decreases the pullout strength of the pedicle screw: a biomechanical study in adult cadavers.

The pullout strength of the pedicle screws after direct vertebral rotation (DVR) maneuver is not known. This biomechanical study was performed to quantitatively analyze the pullout strength of a pedicle screw after DVR maneuver using human cadaveric vertebrae. Thoracic vertebral bodies from three cadavers were harvested and stripped of soft tissues. Thirty pedicles of 15 vertebrae were separated into two groups after bone mineral density measurements. Polyaxial 5.5 mm pedicle screws with appropriate length were inserted with a freehand technique for each pedicle. One Kirschner wire was inserted to the anterior part of each vertebral corpus the half depth of each corpus was embedded into PVC pipes using polyester paste. In the DVR group, each screw was pulled horizontally with 2 kg (~20 N) load over a screwdriver rigidly attached to the screw, and a DVR maneuver was simulated. The control group did not load with a DVR maneuver. Samples were placed on a universal testing machine and pullout loads were measured. The Mann-Whitney U test was utilized, and the P value <0.05 was considered as statistically significant. In the DVR group, the mean pullout strength was 183.35 N (SD ± 100.12), and in the control group, the mean pullout strength was 279.95 N (SD ± 76.26). Intergroup comparisons revealed that DVR maneuver significantly decreases the pullout strength (P = 0.012). The results of this study confirm that the pullout strength of pedicle screw significantly decreases by approximately 35% when DVR maneuver is applied.

Comparison of serum NEDD-9, CA 15-3, and CEA levels and PET metabolic parameters in breast cancer patients with 18 F-FDG PET / CT.

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.

18F-FDG PET/CT in Xanthoma Disseminatum.

A 64-year-old woman who had yellowish orange-colored, sharp-edged, and flat skin plaques and back pain for about a year was referred for F-FDG PET/CT imaging and her bone marrow biopsy revealed 10% to 20% atypical plasma cells suggestive of monoclonal gammopathy. PET/CT showed linear F-FDG uptake on the surface of the skin on the neck, axillary, chest, inframammary, and inguinal regions. Punch biopsy revealed numerous histiocyte infiltrates with large vacuoles, xanthomized cytoplasm in the dermis, and midsection, and there are several Touton-type giant cells supporting the preliminary diagnosis of xanthoma disseminatum.

The Role of 18F-FDG PET/CT in staging of gallbladder carcinomas.

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.

The Prognostic Value of 18F-FDG PET/CT and KRAS Mutation in Colorectal Cancers

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 18F-fluoro-2-deoxy-glucose positron emission tomography/computed tomography (18F-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. 18F-FDG PET/CT study was performed for pretreatment staging. The maximum standardized uptake value (SUVmax) 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 SUVmax of patients with primary tumor was estimated to be 21.1±9.1 (range= 6.0-47.5). Mean tumor SUVmax 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 SUVmax is a negative prognostic factor.

Metabolic Characteristics and Diagnostic Contribution of 18F-FDG PET/CT in Gastric Carcinomas

Objectives: The aim of this study was to evaluate 18F-fluoro-2-deoxy-glucose (FDG) uptake patterns in primary tumors and metastatic lesions, and also to assess the diagnostic contribution of positron emission tomography/computed tomography (PET/CT) in the initial staging of gastric cancer (GC). Methods: The total number of 341 patients with GC were included in this study. All 18F-FDG PET/CT imagings were performed for initial staging. The maximum standardized uptake value (SUVmax) of primary tumor, obtained from 18F-FDG PET/CT imaging was compared between subtypes of GC. Results: Mean SUVmax of 339 patients' primary tumor was 12.9±8.6. The highest mean SUVmax was detected in patients with medullary subtype GC (17.8±9.9) while the lowest mean SUVmax (9.7±7.6) was seen in signet ring cell carcinoma (SRCC). The primary mean SUVmax was found statistically higher in tubular adenocarcinoma (TAC) group than SRCC group (p<0.001). Higher SUVmax values were found statistically significantly correlated with advanced age (aged ≥60) and increased tumor size (>3 cm) in patients with TAC (p=0.03). Primary tumor SUVmax was found statistically higher in regional lymph node (RLN) positive patients than in RLN negative patients in TAC and SRCC groups (p<0.001 and p=0.012, respectivelly). Also, in patients with SRCC, SUVmax was significantly higher in the distant metastatic group than in the group without metastasis (p=0.025). Conclusion: Increased primary tumor SUVmax was associated with some of clinical parameters such as age and RLN metastasis in patients with TAC. However, there was no relationship between distant metastatic state and primary tumor 18F-FDG uptake in TAC. However, high SUVmax of primary tumor in SRCC was associated with regional and distant metastasis, and primary tumor 18F-FDG uptake may be a prognostic value for this subgroup.