Competing Risks Analysis of Predictors of Delisting Owing to Tumor Progression in Liver Transplant Candidates with Hepatocellular Carcinoma

Abstract

Orthotopic liver transplantation (OLT) is potentially curative for patients with early stage hepatocellular carcinoma (HCC). However, tumor progression before OLT remains a problem. Ninety-three patients were listed for transplantation with HCC or diagnosed with HCC following listing between March, 1997 and September, 2001. Modified TNM Stage was 1/11 in 82 patients and III in 11 patients. Seventy-one patients (76%) were transplanted with a median waiting time of 3.4 months, and 22 (24%) patients were delisted owing to tumor progression (14), noncompliance (5), and death from liver failure (3). Using a COx model competing risks approach, higher baseline alpha-fetoprotein (AFP) ≥ 100 ng/mL was the only factor independently associated with a higher hazard rate of delisting owing to tumor progression (p = 0.00003), whereas four separate factors were independently associated with a lower hazard rate of transplantation: more recent listing year (1999-2001, p = 0.010), blood type O (p = 0.013), Stage I HCC (p = 0.029), and serum bilirubin < 4 mg/dL (p = 0.032). By logistic regression, AFP ≥ 100 ng/mL was the only factor that significantly influenced the probability of delisting owing to tumor progression (p = 0.001). In conclusion, the initial AFP level may be useful along with tumor stage in defining an urgency score for liver transplant candidates with HCC.