What is peritoneal carcinomatosis, and what are its CT and MR imaging features?
Peritoneal carcinomatosis is a more common condition due to the peritoneal spread of carcinoma. Common sites of origin include the ovary, stomach, large bowel, and pancreas, although any carcinoma can potentially spread to the peritoneal space. Complex ascites with variable attenuation and signal intensity properties may be seen, often in association with peritoneal, mesenteric, or omental masses or infiltrative soft tissue, as well as diffuse peritoneal thickening and enhancement ( Figure 31-3 ). Very high attenuation calcifications may also sometimes be present. A primary tumor, along with lymphadenopathy or distant metastatic disease, may also be seen.