Background and Objectives: Serum alpha-fetoprotein (AFP) is a recognized affordable oncological marker in patients with hepatocellular carcinoma (HCC). However, AFP’s prognostic role has been assessed mainly after specific treatments, and no unanimously recognized cut-offs have been identified. The aim of this study is to investigate the prognostic role of different basal AFP cut-offs on survival and HCC course. Materials and Methods: In this single-center, retrospective study, all patients newly diagnosed with HCC between January 2009 and December 2021 were prospectively enrolled. Only patients suitable for curative HCC treatments were included in the analyses. Patients were stratified according to AFP cut-offs of 20, 200, 400, and 1000 ng/mL, which were correlated with survival outcomes and clinical parameters. Results: A total of 266 patients were analyzed, with a median follow-up time of 41.5 months. Median overall survival (OS) of all cohort was 43 months. At the multivariate Cox-regression analysis, AFP value ≥ 1000 ng/mL correlated with impaired OS (1-year OS: 67% vs. 88%, 5-year OS: 1% vs. 43%; p = 0.005); other risk factors were tumor dimension ≥ 5 cm (HR 1.73; p = 0.002), Child–Pugh class B–C (HR 1.72; p = 0.002), BCLC stage A (vs. 0) (HR 2.4; p = 0.011), and malignant portal vein thrombosis (HR 2.57; p = 0.007). AFP ≥ 1000 ng/mL was also associated with a reduced recurrence-free survival (HR 2.0; p = 0.038), while starting from AFP ≥ 20 ng/mL, a correlation with development of HCC metastases over time (HR 3.5; p = 0.002) was seen. AFP values ≥ 20 ng/mL significantly correlated with tumor size and higher histological grading; starting from AFP values ≥ 400 ng/mL, a significant correlation with Child–Pugh class B–C and female gender was also observed. Conclusions: Basal AFP correlates with relevant outcomes in patients with HCC. It could help identify patients at a higher risk of worse prognosis who might benefit from personalized surveillance and treatment programs. Prospective studies are needed to confirm these results.
