Multimodality imaging approach in identifying invasive hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the 5th most common neoplasm and the 3rd leading cause of cancer related mortality worldwide. Early stages of the neoplasm may be treated curatively with liver resection or orthotopic liver transplant. However, HCC has a high propensity for vascular and locoregional invasion, which can preclude these treatment options. The portal vein is the most invaded structure, while other regional structures affected include the hepatic vein, inferior vena cava, gallbladder, peritoneum, diaphragm, and the gastrointestinal tract. Management of invasive and advanced stages of HCC includes modalities such as transarterial chemoembolization (TACE), transarterial radioembolization (TARE), and systemic chemotherapy, which are non-curative and focus on relieving tumor burden and slowing progression. A multimodality imaging approach is effective in identifying areas of tumor invasion and distinguishing between bland and tumor thrombi. Due to implications in prognosis and management, it is imperative for radiologists to accurately identify imaging patterns of regional invasion by HCC and to distinguish between bland and tumor thrombus in cases of potential vascular invasion.