The mRECIST Classification Provides Insight into Tumor Biology for Patients With Hepatocellular Carcinoma Awaiting Liver Transplantation

With recent changes in United Network for Organ Sharing policy, patients in the United States with hepatocellular carcinoma (HCC) are likely to spend more time on the liver transplantation (LT) waiting list. The increasing wait time will allow for an opportunity to assess tumor biology prior to LT. Modified Response Evaluation Criteria in Solid Tumors (mRECIST) paradigm provides such a framework for this assessment, and yet little is understood of its utility as it would apply for patients listed for LT in the United States. Through a collaboration between the University of California, San Francisco, and the Mayo Clinic, Jacksonville, Florida, the experience of 772 patients listed for LT were retrospectively reviewed to study the impact of immediate mRECIST classification following locoregional therapy (LRT) on pre- and post-LT outcomes. Patients who had progression of disease (PD; n = 72), failed to respond to LRT (n = 89) at any time point, or did not achieve radiologic complete response (CR; n = 224) were all at significant risk for wait-list dropout (odds ratio [OR] = 12.11, 4.81, and 2.48; respectively). CR identified a cohort of patients who were at a reduced risk for wait-list dropout. However, 24.9% eventually required further intervention while waiting for transplant, and as many as 82.4% were found to have residual HCC on explant pathology. Failure to respond to LRT was associated with increased risk for recurrence (OR = 3.00) more so than PD (OR = 1.36), suggesting that despite PD, patients who eventually can respond to LRT may represent favorable candidates for LT. In conclusion, for patients awaiting LT, the mRECIST assessment provides critical guidance for patient management. Although PD portends a poor prognosis, our findings suggest that further aggressive LRT should be pursued because a response to LRT may yield acceptable results for patients awaiting LT as well as after LT.