Tumor markers and18F-FDG PET/CT after orchiectomy in seminoma:Is there any correlation?

Abstract

OBJECTIVE\nThe aim of our study was to analyze the potential relationship between tumor markers and 18F-fluorodoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) results in patients affected by seminoma.\n\n\nMATERIAL AND METHODS\n65 18F-FDG PET/CT scans of 41 patients with diagnosis of seminoma were analyzed and compared to alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG). PET/CT studies were analyzed qualitatively and measuring the maximum and mean standardized uptake value body weight max (SUVbwmax, SUVbwmean), maximum SUV lean body mass (SUVlbm), maximum SUV body surface area (SUVbsa), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of hypermetabolic lesions. All values were compared with serum markers.\n\n\nRESULTS\n31 PET/CT studies were true negative, 28 true positive, 6 false positive and 0 false negative with sensitivity of 100%, specificity of 84%, negative predictive value of 100%, positive predictive value of 82% and accuracy of 91%. No correlation between PET results and tumor marker levels was found and also between AFP and PET/CT semiquantitive parameters. All semiquantitative PET parameters were significantly related to hCG level.\n\n\nCONCLUSIONS\n18F-FDG PET/CT has good accuracy in evaluating patients with relapsed seminoma. hCG levels were significantly correlated with metabolic PET/CT parameters.