Konstitüsyonel semptomu olan hastalarda FDG-PET/BT'nin tanisal değeri

Introduction: We investigated the role of FDG-PET/CT for diagnostic evaluation of patients admitted with constitutional symptoms and suspicious for malignancy. Method: In this retrospective, cross-sectional study, we enrolled 155 consecutive patients with constitutional symptoms (fever, night sweats, weight loss, fatique, and arthralgia) between January 2017 and December 2019 evaluated with FDG-PET/CT for diagnosis/differential diagnosis of malignancy at outpatient or inpatient clinics of İstanbul Medical Faculty, Department of Internal Medicine, Division of General Internal Medicine. All PET/CT was performed with 6-slice multidetector CT integrated high resolution scanner (Siemens Biograph LSO HI-RES PET-CT) in Nuclear Medicine laboratory of our institute, with at least 4 hours of fasting and injection of 8-15 mci FDG intravenously. Any increased FDG accumulation except for physiological uptake area of body (buralarda da normalin üstü pozitif oluyor ama sen ne yazdıysan onu çevirdim) was accepted as pathologic in assessment of images. Before PET/CT, demographics and baseline laboratory or diagnostic tests of all patients were recorded. Results: Overall 144 patients (59 female/85 male, 41/59%, respectively) with mean age of 58,05±17,24 (range 18-84 year, mean age of female 60,34±16,32 and male 56,46±17,77) were included. Mean duration of symptoms was 4.01±4.46 months. Of 95,1% (n=137) patients got diagnosis, while remaining 4,9% (n=7) not. The most frequent diagnosis in identified group was malignancy in 57,7% (n=79), followed by rheumatic diseases in 16,1% (n=22), infections in 13,9% (n=19), and other diseases in 12,4 % (n=17). Of 82,6% of cases, FDG-PET/CT gave additional benefit for diagnosis of constitutional symptom. PET/CT showed 86,8% sensitivity, 100% specificity, 100% positive predictive value, 28% negative predictive value, 13,1% false negativity, and no false positivity. Conclusion: FDG-PET/CT seems to be a helpful imaging technique with high sensitivity and spesificity for diagnosis and differential diagnosis of malignancy in patients with constitutional symptoms.