Search

IntroductionThere is no consensus about the standardized uptake value maximum (SUVmax) cut-off value to characterize pleural thickening worldwide. Sometimes, this causes unnecessary invasive diagnostic procedures. Our first aim is to determine a cut-off value for SUVmax. Secondly, we try to answer the following question: If we use this cut-off value together with morphological parameters, can we differentiate benign thickening from malignant pleural mesothelioma (MPM) more accurately?Material and methodsThirty-seven patients who underwent 2-deoxy-2-fluoro-D-glucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) before pleural biopsy were included the study. All of patients had histopathologically proven primary pleural disease. Their [18F]FDG-PET/CT imaging reports were re-assessed. If a patient’s SUVmax or size of the thickening was not mentioned in the report, we calculated it with their [18F]FDG-PET/CT.ResultsAge, pleural effusion, size, and SUVmax were found to have a relationship with MPM. We found the size > 14 mm, and SUVmax > 4.0 as cut-off values for MPM. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for size > 14 mm were found to be 86.4%, 85.2%, 82.6%, 88.5%, respectively. For SUVmax > 4.0, sensitivity, specificity, PPV, NPV were 90.9%, 87.0%, 85.1%, 92.2%, respectively.ConclusionsIf a patient has SUVmax > 4.0 and/or size > 14 mm, the risk of MPM is high. These patients should undergo biopsy. If a patient’s SUVmax < 4.0, size < 14 mm and does not have pleural effusion, he/she has low risk for MPM. These patients can undergo the follow-up. If a patient’s SUVmax < 4, size < 14, and has pleural effusion the MPM risk is approximately 4%. These patients can undergo biopsy/cytology/follow-up. Novel studies are needed for these patients.

Aim: Thyroidal incidentalomas (Tis) detected by F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18FDG PET/CT) may be associated with three different causes that include metastasis of another malignancy, primary thyroid gland malignancies and lastly benign thyroidal nodules, all require different clinical approaches. For appropriate treatment, quick characterization of the Ti is important, preferably with a lesser invasive method. Our aim was to determine whether the characterization of TIs can be performed with FDG-PET/CT, due to contribute faster diagnosis, and initiation of the therapy.Material and Methods: Forty-four patients with detected TIs in FDG-PET/CT were included in the study. The relationship between metabolically/morphological parameters and pathology results were evaluated statistically. If two subsequent cytology were negative, nodule accepted as benign. If cytology result was suspected or malignant, histopathological confirmation was made. For these patients, histopathological results were accepted as definite diagnosis. Results: Malignant thyroidal pathologies were detected in 29.5% of patients. We could not find any significant relationship between age, nodule size and SUVmax value and pathology results. According to ROC analysis, there were not any cut-off value for nodule size and SUVmax. Similar results were also obtained for papillary carcinoma as a special subgroup.Conclusion: Characterisation of TIs could not be performed by using age, nodule size and SUVmax. Therefore, TIs which detected by FDG-PET/CT should be examined pathologically due to high risk of malignancy.Keywords: Thyroidal incidentalomas; FDG-PET/CT; malignant; characterization.

F-Fluorodeoxyglucose (F-FDG) PET/CT represents an imaging modality that is gaining increasingly more prominence in screening, staging, and therapeutic monitoring of malignant diseases. An incidental focus of uptake in different regions of the body is not an uncommon finding during PET/CT imaging. Patients with incidental gastrointestinal tract findings comprise ∼3% of the overall patient group. The aim of the current study was to provide contributory information in relation to the answer on the most appropriate approach in cases with incidental colonic F-FDG uptake.A retrospective examination was performed on PET/CT results of 5258 patients. Of these, 152 were recommended to undergo colonoscopy because of the presence of suspicious foci and 31 underwent colonoscopy within 60 days with biopsy from all visible lesions. These dates were also examined.Of the 24 patients undergoing colonoscopy with a suspicion of malignancy, five (20.83%) had no pathological findings. Of the 19 (79.17%) cases with a pathological finding in endoscopy, histopathology showed a benign lesion in five (20.83%), premalignant lesion in seven (29.17%), and a malignant lesion in seven (29.17%). Among seven patients undergoing colonoscopy because of a suspicion of inflammatory bowel disease, five were free of pathological signs and two patients with pathological endoscopy findings had nonspecific inflammation as documented by histopathological examination.Colonoscopic and histopathological examination of the increased foci of colonic F-FDG uptake incidentally detected at PET/CT seems to be a plausible approach.