Alpha-Fetoprotein Combined with Radiographic Tumor Burden Score to Predict Overall Survival after Liver Resection in Hepatocellular Carcinoma

Abstract

We evaluated whether combining the radiographic tumor burden score (TBS) and alpha-fetoprotein (AFP) level could be used to stratify overall survival (OS) among hepatocellular carcinoma (HCC) patients after liver resection (LR). Patients who underwent LR for Barcelona Clinic Liver Cancer stage 0, A, or B HCC between 2011 and 2018 were enrolled. TBS scores were calculated using the following equation: TBS² = (largest tumor size (in cm))² + (tumor number)². Among 743 patients, 193 (26.0%) patients had a low TBS (<2.6), 474 (63.8%) had a moderate TBS (2.6-7.9), and 75 (10.1%) had a high TBS (>7.9). Those with a TBS ≤ 7.9 and AFP < 400 ng/mL had a significantly better OS than those with a TBS > 7.9 and an AFP < 400 ng/mL (p = 0.003) or ≥ 400 ng/mL (p < 0.001). A multivariate analysis using TBS ≤ 7.9 and AFP < 400 ng/mL as the reference values showed that a TBS > 7.9 and an AFP < 400 ng/mL (hazard ratio (HR): 2.063; 95% confidence interval [CI]: 1.175-3.623; p = 0.012) or ≥ 400 ng/mL (HR: 6.570; 95% CI: 3.684-11.719; p < 0.001) were independent predictors of OS. In conclusion, combining radiographic TBSs and AFP levels could stratify OS among HCC patients undergoing LR.

Keywords: alpha-fetoprotein; hepatocellular carcinoma; liver resection; tumor burden score.

Figure 1

Cutoff tumor burden score (TBS) values were determined by overall survival using X-tile, a bioinformatics tool created by Camp et al. (A) Data represented graphically in a right-triangular grid in which each pixel represents the data from a given set of divisions. The vertical axis represents all possible “high” populations, with the size of the high population increasing from top to bottom. Similarly, the horizontal axis represents all possible “low” populations, with the size of the low population increasing from left to right. (B) The number of patients in each group for a given set of divisions. (C) Kaplan–Meier curves show significant differences in overall survival among patients with a low TBS (i.e., <2.6), moderate TBS (i.e., 2.6–7.9), and high TBS (i.e., >7.9; p < 0.001).

Figure 2

Kaplan–Meier curves demonstrating differences in overall survival among patients with tumor burden score (TBS) ≤ 7.9/α-fetoprotein (AFP) ≤ 400 ng/mL, TBS ≤ 7.9/AFP > 400 ng/mL, TBS > 7.9/AFP ≤ 400 ng/mL, and TBS > 7.9/AFP > 400 ng/mL.