MRI diagnosis of peritoneal carcinomatosis

Objective: To study the MRI feature of peritoneal carcinomatosis and to evaluate the diagnostic value of diffusion-weighted imaging (DWI). Methods: MRI of 49 patients with peritoneal carcinomatosis confirmed by surgery and pathology was reviewed. The MRI sequences included T1-, T2-, diffusion-weighted, and gadolinium-enhanced 3D THRIVE sequences. The distribution, size and DWI signal intensities of the tumors were graded by two radiologists in consensus. Results: Of 348 sites of peritoneal carcinomatosis, the imaging findings included linear thickening of parietal and visceral peritoneum (4), irregular linear thickening (35), serosal thickening of the intestinal surface (11), omental stranding (22) and caking (14), mesentery stranding (12), nodules and masses in the abdominal cavity (46), cystic masses (6), ascites (45), primary abdominal carcinoma (25) and lymphadenopathy (12). Bivariate correlation analysis showed weak correlation between the size and DWI signal intensities (Kendall correlation coefficient = 0.438; Spearman correlation coefficient = 0.473). Conclusion: MRI with DWI can depict the primary abdominal carcinoma and extent of peritoneal carcinomatosis. (authors)