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Model for end‐stage liver disease (MELD) exception for cholangiocarcinoma or biliary dysplasia

Cholangiocarcinoma (CCA) is a devastating disease with few treatment options. The incidence of CCA in the United States is on the rise and is currently estimated at 3,000 to 4,000 cases per year, with the incidence being especially high in patients with primary sclerosing cholangitis (PSC). Survival after onset of symptoms of unresectable CCA is 12 to 16 months. There are 2 presentations of CCA: intrahepatic mass within the hepatic parenchyma, and periductal involvement of the major intrahepatic and/or extrahepatic bile ducts. Intrahepatic CCA is best treated by liver resection because liver transplantation (LT) for this condition is fraught with rapid recurrence and has been abandoned by most centers. Periductal CCA that is limited to the extrahepatic duct below the bifurcation of the common hepatic duct is also best treated by surgical resection. Tumors arising in the hilus are often treated by surgical resection, but many are unresectable because of vascular encasement, extension of tumor to secondary branches of the intrahepatic ducts, or underlying PSC. LT alone for these tumors is inadequate as recurrence is high, and the long-term survival rate is 25%. Even patients with PSC and incidental CCA discovered in the explanted liver have a poor prognosis after LT alone. However, excellent long-term survival (78% at 5 years) has been achieved in carefully selected patients with unresectable hilar CCA and hilar CCA arising in the setting of PSC treated with neoadjuvant chemoradiotherapy before LT. Published experiences from the University of Nebraska and the Mayo Clinic at Rochester, MN, have demonstrated long-term survival after LT for unresectable hilar CCA and hilar CCA arising in the setting of PSC. Both centers used high-dose neoadjuvant radiotherapy with chemosensitization and operative staging to exclude patients with regional lymph node metastases before LT. Efficacy of this approach is demonstrated by comparing these results with the natural history of the disease, which has a 50 to 70% mortality rate within 12 months. Heimbach and colleagues demonstrated that neoadjuvant therapy and LT in patients with localized, node-negative disease achieves results similar to LT for other chronic liver diseases (i.e., hepatitis C virus infection, PSC) and hepatocellular carcinoma. Moreover, survival after LT in patients with unresectable hilar CCA or hilar CCA arising in the setting of PSC exceeded survival in patients who underwent resection. Region Review Board 7 members agreed to Model for End-Stage Liver Disease (MELD) score exception guidelines in September 2002. The aims of these guidelines were to provide the opportunity for deceased-donor LT to patients with unresectable CCA and CCA arising in the setting of PSC, determine the risk of disease progression while awaiting LT, and retain incentives for living-donor LT and use of extended-criteria donor livers. These guidelines recommend MELD score exceptions for patients after completion of neoadjuvant therapy and operative staging to accurately assess the risk of disease progression while awaiting LT. When the guidelines were approved, the initial MELD score of 20 was matched to the score assigned to patients with stage I hepatocellular carcinoma (which no longer receives an assigned or adjusted MELD score). The interval for additional score adjustments was 6 months, as