KEY FACTS
Terminology
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Peritoneal spread of tumor from epithelial malignancy resulting in peritoneal thickening, omental infiltration, serosal implants, and ascites
Imaging
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Implants develop where peritoneal fluid collects: Dome of liver, omentum, paracolic gutters, and pelvic recesses
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Peritoneal masses may be solid, cystic, or mixed, depending on primary neoplasm
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Hypoechoic rind-like thickening of peritoneum or discrete irregular nodular masses along peritoneum
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Omental involvement may be nodular or diffuse, producing an omental cake
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Thickened and hypoechoic or heterogeneous with preserved islands of echogenic fat
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Ascites: Complex with septations or internal echoes (jiggle with transducer pressure)
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Thickening of mesenteric leaves due to desmoplastic reaction; typically mesenteric side of terminal ileum
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Color Doppler flow in solid omental/peritoneal deposits
Top Differential Diagnoses
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Pseudomyxoma peritonei
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Peritoneal mesothelioma
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Peritoneal tuberculosis
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Peritoneal sarcomatosis
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Peritoneal lymphomatosis
Clinical Issues
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Present with abdominal distension and pain, weight loss, malaise, fever
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May have elevated tumor markers such as CA125 or CEA
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Prognosis variable depending on primary tumor but generally poor prognosis
Scanning Tips
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Use linear transducers to evaluate anterior peritoneum
with adjacent ascites 
and bowel 
.
and a thick lobular omental cake 
from pancreatic carcinomatosis.
. Color flow is present within the omentum. A small amount of ascites 
is noted.
anterior to the liver 
, representing mucinous carcinomatosis from appendiceal carcinoma.
being biopsied using a needle guide 
.
, growing out through the umbilicus 
. Biopsy of the umbilical mass showed metastatic adrenal cortical carcinoma.
