Predictive value of PET–CT imaging versus AGO-scoring in patients planned for cytoreductive surgery in recurrent ovarian cancer

Abstract

Objective To assess the predictive value of positron emission tomography computed tomography (PET–CT) imaging in comparison to AGO-scoring in patients planned for cytoreductive surgery in recurrent ovarian cancer. Materials and methods 33 patients who had received a PET–CT for suspicion of recurrent ovarian cancer between 12/2003 and 08/2007 were included in the retrospective analysis. Indication for PET–CT was based on blood tumor markers Ca 125 or Ca 72-4 and clinical symptoms. Scanning was performed on a Philips Gemini System covering the body from the neck to the thighs one hour after administration of 200 MBq fluorodesoxyglucose. PET–CT, surgery and the patient records were reviewed to analyze the predictive value of PET–CT in comparison to an AGO-scoring system based on clinical parameters with regard to the prediction of full resectability of abdominal tumor spread. Results The statistical analysis of this data showed a sensitivity of 73% (95% C.I., 39–94%) and specificity of 80% (95% C.I., 29–97%) for AGO-scoring with a positive predictive value of 89% and a negative predictive value of 57%. PET–CT achieved a sensitivity of 100% (95% C.I., 72–100%) and specificity of 60% (95% C.I. 15–94%), with a positive predictive value of 85% and negative predictive value of 100%. Further analysis of the data of operated patients with concordant PET–CT and AGO-score (12/16) showed a very good prediction of full resectability with a sensitivity of 100% (95% C.I., 63–100%), specificity of 75% (95% C.I., 20–96%), positive predictive value of 89% and negative predictive value of 100%. Conclusion PET–CT and the AGO-score offer good tools to determine patients for full resectability in recurrent ovarian cancer. PET–CT has a higher negative and the AGO score a higher positive predictive value, and the combination of both improves the diagnostic accuracy.