Liver cancer imaging: The need for accurate detection of intrahepatic disease spread

The last ten years have seen dramatic changes in the therapeutic approach t o both primary (i.e., hepatocellular carcinoma: HCC) and secondary (i.e., m etastatic lesions) focal liver malignancies. This has been due to the incre asing proliferation of new modalities, including percutaneous ablative ther apies (ethanol injection: PEI; radiofrequency: RF; laser; microwaves), angi ographic therapies (segmental chemoembolization; hypoxic perfusion) and liv er transplantation (OLT), in addition to a greater acceptance of pre-existi ng modalities (resection; systemic chemotherapy). Thus, a main aim of curre nt medical management is to select for each patient the therapeutic modalit y which will provide the highest success rate, fewest risks and lowest cost s for each given situation. However, in order to decide on the appropriate therapeutic choice, the accu rate diagnosis of neoplastic lesions by means of one or more imaging modali ties (ultrasound: US; computed tomography: CT; magnetic resonance: MR) is m andatory. This imaging work-up can be viewed as having three purposes: lesi on detection, lesion characterization, intrahepatic and extrahepatic cancer staging. The present paper is concerned primarily with the imaging approac h to liver lesion detection.