Staging and Prognostic Models for Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma

There are several important roles that staging systems and prognostic models play in the modern medical care of patients with cancer. First, accurate staging systems can assist clinicians by identifying optimal treatment selection based on the scope of disease at the time of diagnosis. Second, both physicians and patients may infer prognostic information from staging and models that may help decision makers identify appropriate therapies for individual patients. Third, in research, there is benefit to classifying patients with disease into subgroups ensuring greater parity between experimental and control arms. Staging systems in most solid organ malignancies rely heavily on an accurate pathologic assessment of the tumor (size, site, number of tumors, locoregional spread, and distant spread). Another consideration in primary liver cancer, such as hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), is the fact that the underlying liver function can significantly impact patient survival. In HCC, there are at least a dozen options that have been proposed for staging the disease. Herein, we review the most widely used systems and discuss their strengths and weaknesses. Prognostic models and nomograms are also discussed for a variety of subpopulations with HCC. Interestingly, until 2010, the staging system proposed by the American Joint Committee on Cancer for ICC was identical to HCC. The modern staging system, unique to ICC, is reviewed, and future modifications are identified with the primary supporting literature discussed.