Clinical characteristics and outcome of patients with fibrolamellar hepatocellular carcinoma: an analysis of a large population using real-world data

<h3>Background</h3> Fibrolamellar carcinoma (FLC) is a rare subtype of hepatocellular carcinoma (HCC), accounting for ∼1%-9% of all HCC cases. The limited literature and lack of studies on FLC present significant challenges. <h3>Patients and methods</h3> We conducted a retrospective analysis using TriNetX data to evaluate patients' characteristics and outcome in terms of overall survival (OS), among patients with FLC. Additionally, we conducted further analysis to evaluate differences in terms of patient characteristics and outcome between FLC and HCC; specifically, we compared patients with FLC and HCC who underwent any type of treatment, patients with FLC and HCC in the early stage who underwent surgery and patients with FLC and HCC with advanced disease treated in first-line therapy. Also, the same analyses were carried out after propensity score matching. The primary endpoints were features of patients and OS of FLC, and HCC versus FLC, particularly regarding systemic therapy and surgical interventions. <h3>Results</h3> In the FLC group, 87 patients were analyzed, with a median OS (mOS) of 56.1 months. Comparing HCC and FLC, 211 523 HCC patients and 87 FLC patients were included, showing no significant mOS difference [mOS 46.9 months versus 76.5 months, hazard ratio (HR) 1.21, <i>P</i> = 0.27], revealing significant differences in mean age (<i>P</i> < 0.0001) and racial distribution (<i>P</i> < 0.03). After propensity scoring, significant difference in α-fetoprotein (AFP) (<i>P</i> = 0.003) was discovered. In surgical cases, 116 276 HCC patients and 51 FLC patients had similar mOS (84.6 months versus 78.4 months, HR 0.94, <i>P</i> = 0.77), with significant differences in mean age (<i>P</i> < 0.001), racial distribution (<i>P</i> = 0.0002), and body mass index (BMI) (<i>P</i> = 0.04). The propensity score revealed a significant difference in aspartate aminotransferase value (<i>P</i> = 0.04). In first-line treatments, 6090 HCC patients and 22 FLC patients showed no statistical difference in mOS (8.1 months versus 26.0 months, HR 1.44, <i>P</i> = 0.13), but differences were found in gender distribution (<i>P</i> = 0.0003), mean age (<i>P</i> < 0.001), albumin levels (<i>P</i> = 0.01), and AFP values (<i>P</i> = 0.02). After propensity score matching, the analysis confirmed significant differences in AFP (<i>P</i> = 0.04) and total bilirubin value (<i>P</i> = 0.02). <h3>Conclusion</h3> The current analysis showed no statistically significant differences in OS between patients with HCC and those with FLC at any stage, regardless of whether they received surgical or medical treatment. Significant statistical features were highlighted between the groups.