How is colorectal metastasis detected?

CT/surgery.: These are often detected on ct scan, but the most definitive way to detect this is by surgery, often done during resection of primary tumor. This is one reason why the dukes classification is used, as the invasiveness is determined at surgery. Stage a - to submucosa, b - to muscularis, c - to lymph nodes, d - distant metastasis. Organs of metastasis also show signs - liver, bone lung.

Imaging : There is growing evidence that CT, MRI and PET/CT are complementary rather than exclusive techniques in detection of colorectal metastasis. CT is the most widely used staging modality,but PET/CT is a more sensitive & specific modality improving detection of both liver & extra hepatic mets. MRI is rarely used as a primary tool in liver mets diagnosis, but its regarded as a problem solving technique