A prospective study evaluating diffusion weighted magnetic resonance imaging (DW-MRI) in the detection of peritoneal carcinomatosis in suspected gynecologic malignancies

• Diffusion-weighted MRI (DW-MRI) is superior to CT in detecting right diaphragm disease found at surgery.
• DW-MRI and CT are equivalent in detecting disease involving the majority of sites important for surgical planning.
• Interobserver radiologist agreement is better for DW-MRI than for CT in detecting disease found at the time of surgery.

ObjectivesTo evaluate and compare the ability of DW-MRI and CT to detect sites of peritoneal dissemination in gynecologic malignancies. The reproducibility of DW-MRI and CT interpretation between radiologists was also assessed.MethodsSingle institution prospective cohort study of women with suspected advanced gynecologic cancer who underwent surgical staging from 2010 to 2013. Participants underwent both DW-MRI and contrast-enhanced CT prior to surgery. Radiologists and surgeons were blinded, respectively, to surgical and DW-MRI results. The area under the receiver operator characteristic curve (AUC) was calculated for each disease site for CT and DW-MRI and compared to surgical findings. Kappa statistics quantified interobserver agreement between both radiologists.ResultsTwenty seven patients were enrolled. Mean age at surgery was 59 years. Ninety percent of participants had stage IIIC/IV disease. For right diaphragm disease, the AUC for DW-MRI was 0.95 compared to 0.81 for CT. For left diaphragm disease, the AUC was 0.89 for DW-MRI compared to 0.74 for CT. The AUC was similar for DW-MRI and CT for omental disease (0.79 versus 0.64); the liver surface (0.61 versus 0.67); bowel mesentery (0.73 versus 0.64); and cul de sac (0.75 versus 0.64). Interobserver agreement for DW-MRI was greater than CT for omental, Morrison's pouch, liver surface, and right diaphragm disease.ConclusionsDW-MRI detects right diaphragmatic disease found at surgery with greater accuracy than CT. For other disease sites key to surgical planning, DW-MRI is equivalent to CT. Interobserver agreement was superior for a majority of disease sites evaluated by DW-MRI compared to CT.