History
Presenting Complaint
Patients may present with symptoms relating to:
- Liver enlargement (pain, bloating)
- Liver failure (jaundice, haematemesis, bloating/ascites)
- Advanced cancer symptoms (anorexia, cachexia, weight loss, fatigue)
About 1/3rd of patients are asymptomatic. Patients with oligometastatic disease tend to fall into this group.
Past History
A past history of cancer suggests the likely primary site but new primaries may also be responsible (particularly if the previous primary rarely spreads to the liver, eg. sarcoma, head and neck cancer, and there are no other metastatic deposits).
Examination
Examination may be unremarkable in patients with low volume disease. Advanced cases may have hepatomegaly and signs of hepatic failure (bruising, ascites, jaundice, splenomegaly).
Imaging
Ultrasound
Ultrasound is often an initial test for patients with symptoms suggestive of a liver disorder. It has poorer resolution than CT and may not be able to distinguish small lesions from ordinary liver parenchyma. It is a good modality for providing guidance to percutaneous biopsy if required, and if the lesion is visible on US.
CT
CT provides better delineation of liver lesions, but usually only when contrast is present. It can detect smaller lesions than ultrasound but is more expensive.
MRI
MRI is a far more expensive test but may be used when CT findings are equivocal.
PET
PET is a useful staging tool as it is able to detect small liver metastases; it is usually not indicated for further investigation of established liver lesions unless there is some question as to their malignant nature (or to find other deposits in the body).
Histological Diagnosis
Histological diagnosis is not usually required in the setting of metastatic disease with a known primary. Exceptions are when:
- The primary is thought to be an unlikely source of the metastatic disease
- There is some question as to the nature of the lesion (?benign/malignant)
In these cases, percutaneous biopsy with US or CT guidance is necessary.
Staging
For almost all sites, liver metastases count as M1 disease. In a few specific sites (colorectal), liver metastases alone are counted as M1a disease as they are associated with a better prognosis (if resectable).