• Emmanouil Panagiotidis, Ioannis E Datseris, Phoebe Rondogianni, Evangelia Vlontzou, Maria Skilakaki, Demetrios Exarhos, and Aristotelis Bamias.
• Departments of aNuclear Medicine bRadiology, Evangelismos Hospital cDepartment of Clinical Therapeutics, Athens University, Medical School, Athens, Greece.
• Nucl Med Commun. 2014 Jun 1; 35 (6): 598-605.

AimThe purpose of this prospective study was to investigate the role of 2-(fluorine-18)-fluoro-2-deoxy-D-glucose ((18)F-FDG) PET/computed tomography (CT) in the diagnosis of recurrent colorectal cancer (CRC) in patients with increased tumor markers and negative contrast-enhanced computed tomography (CeCT) results.Material And MethodsForty-three patients (27 male; median age 66 years, range 31-93 years) with increasing tumor markers and negative CeCT during follow-up for treated CRC underwent (18)F-FDG PET/CT examinations. The serum values of carcinoembryonic antigen (CEA) (n=29) and CA 19-9 (n=20) were normal after completion of treatment, with subsequent increasing concentrations.ResultsAmong the 43 patients, (18)F-FDG PET/CT was true positive in 32 (74.4%), false positive in two (4.7%), false negative in one (2.3%), and true negative in eight (1%) patients. On the patient-basis analysis, (18)F-FDG PET/CT had a sensitivity of 97% (confidence interval: 0.82-0.99), a specificity of 80% (0.44-0.96), a positive predictive value of 94% (0.78-0.98), and a negative predictive value of 88% (0.5-0.99). There was no statistically significant correlation between CRC recurrence and CEA and CA19-9 levels (P=0.561 and 0.55, respectively). Only in the group of patients (n=6) with both tumor markers increased did (18)F-FDG PET/CT have 100% accuracy in revealing recurrent disease.Conclusion(18)F-FDG PET/CT is highly sensitive in the diagnosis of recurrent CRC in patients with increasing levels of tumor markers and negative CeCT regardless of the type or level of tumor marker; however, the combination of elevated CEA and CA 19-9 increases the likelihood of (18)F-FDG in detecting recurrence.

26 keywords...

hide…