Association between posttreatment α-fetoprotein reduction and outcomes in real-world US patients with advanced hepatocellular carcinoma.

BACKGROUND: Clinical trials suggest α-fetoprotein (AFP) reduction may be prognostic among patients with advanced hepatocellular carcinoma. However, the association of AFP reduction with outcomes in real-world settings is unclear.

METHODS: Patients with advanced hepatocellular carcinoma between January 1, 2011, and June 30, 2021, first-line tyrosine kinase inhibitor, and baseline and posttreatment AFP values (closest to 8 ± 2 weeks after first-line initiation) were included. AFP reduction was defined as ≥20% decrease from baseline vs <20% or no decrease. Real-world overall survival and progression-free survival (rwPFS) were defined as time from posttreatment AFP measurement to death, and the first progression event or death, respectively. Adjusted hazard ratios (aHRs) were estimated using Cox proportional hazards models adjusted for potential confounders and baseline AFP. Effect modification by baseline AFP and hepatocellular carcinoma risk factors was assessed.

RESULTS: Among 533 patients, median baseline AFP was higher in those with AFP reduction than those without (N = 166, 210 µg/L vs N = 367, 150 µg/L). There was a 35% decrease in hazard of death for patients with reduction vs without (aHR = 0.65; 95% CI, 0.52-0.81; median, 10.3 vs 5.9 months). Results were similar for rwPFS (aHR = 0.66; 95% CI, 0.54-0.81; median, 4.6 vs 2.6 months). AFP reduction was associated with better outcomes among patients with baseline AFP ≥400 µg/L or with history of hepatitis B virus, hepatitis C virus, or alcohol use. Only the interaction between baseline AFP and reduction in association with rwPFS was statistically significant.

CONCLUSIONS: For certain etiologies, posttreatment AFP change may be more important than baseline AFP for prognosis. Further work should characterize the prognostic implications of longitudinal AFP changes during treatment.

PLAIN LANGUAGE SUMMARY: The prognostic value of the change in α-fetoprotein (AFP) concentration after treatment initiation is less established, particularly in real-world settings. Longitudinal data from a large nationwide cohort of patients with advanced hepatocellular carcinoma (HCC) treated with first-line tyrosine kinase inhibitor in routine practice revealed that ≥20% reduction in posttreatment AFP levels was associated with better real-world overall survival and progression-free survival after adjusting for baseline AFP levels and other factors. The results also suggested that the associations may be stronger among patients with a history of HCC risk factors (e.g., hepatitis C virus, alcohol) or with higher baseline AFP levels.