DWI predicts surgical outcome in advanced ovarian cancer

Abstract

Purpose: To evaluate the values of DWI-derived tumour burden of peritoneal carcinomatosis (PC) and its biology in determining the surgical outcome in advanced ovarian cancer (AOC). Methods and Materials: Thirty-four AOC patients were prospectively recruited with pre-surgical DWI (b=0, 400, 800 s/mm2 ). Tumours with intermediate apparent diffusion coefficient (ADC) segmented by k-means clustering were used for solid tumour volume (STV) calculation discarding fatty, fibrous or cystic tissues. A functional peritoneal cancer index (fPCI) was generated by adding up all STVs from 13 abdominopelvic regions with additional points if porto hepatis, mesentery or bowel serosa were involved. Mean ADC was measured from 3 selected lesions with the largest STVs. At surgery, the surgical PCI (sPCI), surgical duration and surgical outcome (complete cytoreductive surgery or with residual disease) were recorded. Mann-Whitney U test, Pearson correlation (r) and logistic regressions were performed. Results: Patients who achieved complete cytoreductive surgery had lower fPCI (4.30 vs 10.18) and sPCI (5.70 vs 12.00) but higher ADC (0.97 vs 0.73) than patients with residual disease (p < 0.005). fPCI was significantly correlated with sPCI (r=0.899, p<0.001) and surgical duration (r=0.528, p=0.001). fPCI, sPCI and ADC (r=0.507, 0.529, -0.562) were significantly correlated with residual disease (p<0.005). Both fPCI and ADC were significant in univariate and multivariate analyses (p<0.05; accuracy=82.4%, sensitivity=72.7%, specificity = 87.0%). Conclusion: Pre-surgical fPCI and ADC were significant predictors for complete cytoreductive surgery in AOC.