Supplementary Material for: Impact of Helicobacter pylori on immune checkpoint inhibition in hepatocellular carcinoma: a multicenter study

Background: Immunomodulating effects of Helicobacter pylori (H.pylori) have been shown to inhibit antitumor immunity. Resistance to immune checkpoint inhibitor (ICI)-based therapies is common among patients with hepatocellular carcinoma (HCC).
Objective: The study aims to assess the effect of H.pylori on the outcomes of ICI in patients with HCC.
Methods: We conducted a multicenter study in patients with HCC across a broad range of treatments. Patients received either ICI-based combination regimens or sorafenib-based therapy. H.pylori serostatus and virulence factors were determined and correlated with overall survival (OS), progression-free survival (PFS), and safety across the treatment modalities.
Results: 180 patients with HCC were included; among these, 64 were treated with ICI- and 116 with sorafenib-based regimen. In patients treated with ICI, median OS was shorter in H.pylori-positive patients (10.9 months in H.pylori-positive vs 18.3 months; p=0.0384). H.pylori-positivity was associated with a shorter PFS in ICI recipients (3.9 months vs 6.8 months, p=0.0499). In patients treated with sorafenib, median OS was not shorter among H.pylori-positive patients (13.4 months in H.pylori-positive vs 10.6 months; p=0.3353). Immune-related adverse events and rates of gastrointestinal bleeding were comparable between H.pylori-positive and -negative patients.
Conclusion: H.pylori seropositivity was linked to poorer outcomes in patients with HCC treated with ICI. This association was not observed among patients receiving sorafenib-based therapies.