Table 4.

Advantages and disadvantages of CT, PET/CT and MRI in assessment of peritoneal malignancy

Modality	Advantages	Disadvantages
CT	Cheap Readily accessible Sensitive for disease above diaphragm	Lowest sensitivity and specificity for peritoneal disease Poor at detecting plaque-like mesenteric involvement, small bowel disease and mesenteric disease
PET/CT	More sensitive than CT alone in identifying FDG-avid nodules Sensitive for disease above diaphragm Sensitive in post-operative patients Useful in abdominal wall disease and in the setting of ascites	Poor sensitivity in tumours with low FDG-avidity (e.g. mucionous ovarian malignancy) Physiologic uptake in the stomach, liver, bowel and GU tract limits interpretation Lesions <5 mm are under PET threshold
MRI	DWI imaging very sensitive for disease (per site sensitivity up to 95%) Sensitive for peri-hepatic disease	Costly and time-consuming Requires specialist training Less accurate than PET/CT for lymph node involvement

DWI, diffusion-weighted imaging; FDG, fludeoxyglucose; GU, genitourinary; PET, positron emission tomography.