Functional Imaging of Peritoneal Disease in Ovarian Cancer: Changes in Apparent Diffusion Coefficients Predict Biochemical Response to Chemotherapy

Stavroula Kyriazi^1,2, David J. Collins¹, Veronica A. Morgan², Catherine J. Simpkin², Nandita M. deSouza^1,2

Biochemical (Ca125) monitoring of chemotherapeutic efficacy in advanced ovarian cancer has limited sensitivity early in the course of treatment. Diffusion-Weighted Imaging of peritoneal disease improves anatomical delineation but its role in quantification of treatment response has not been established. This study explores the value of Apparent Diffusion Coefficients calculated for the entire metastatic tumour burden in identifying biochemical response to platinum-based chemotherapy. Although pretreatment ADC values were not predictive, an ADC increase after the first cycle of treatment was highly indicative of chemosensitivity. ROC analysis for %ADC change after the first cycle yielded an area under curve AUC=0.933. These findings may facilitate individualised treatment strategies in advanced ovarian cancer.