The Significance of Preoperative Computed Tomography for Predicting Optimal Cytoreduction in Advanced Ovarian Cancer.

Optimal cytoreduction is the most important prognostic factor in advanced ovarian cancer. Although staging and assessment of operability are made by exploratory surgery, preoperative computed tomography (CT) of the abdomen is regarded as standard. The aim of this study was to examine various CT parameters with regard to prediction of optimal cytoreduction. The retrospective study included 131 patients with ovarian cancer newly diagnosed between 2010 and 2014. Of these, n = 36 with FIGO stage I to IIB were excluded from the study. A preoperative abdominal CT was available for n = 75 of the 95 patients with FIGO stage IIC to IV. The CT scans underwent blinded review. The 11 evaluated CT parameters were examined by means of χ test and logistic regression analysis with regard to the endpoints of macroscopic residual tumour and residual tumour > 1 cm. Survival analyses used the Kaplan-Meier method and log rank test. Of 75 patients, 28 (37.3%) had complete tumour resection and 26 (34.7%) had residual tumour ≤ 1 cm. Residual tumours > 1 cm were found in 21 (28%) patients, five of which were not resectable. Overall survival with residual tumour > 1 cm differed significantly from the group with no macroscopic residual tumour (p = 0.003) and with residual tumour ≤ 1 cm (p = 0.04). The CT parameters tumour foci in the diaphragm, mesocolon, greater omentum and peritoneum as well as ascites correlated with macroscopic residual tumour. In the multivariate logistic regression analysis only the CT parameter intraparenchymal liver metastasis was statistically significant with regard to prediction of suboptimal tumour resection (> 1 cm) (OR 8.04; 95% CI 1.57 - 42.4; p = 0.0134). The sensitivity, specificity, PPV and NPV were 37.5, 89.7, 66.7 and 72.2%. Although risk parameters for suboptimal tumour reduction can be identified by CT of the abdomen, surgical exploration with histological confirmation of the diagnosis is essential because of the poor diagnostic accuracy.