Gastrointestinal Infection Before Immune Checkpoint Inhibition Hinders Treatment Efficacy and Increases the Risk of...

Area of Science:

• Oncology
• Immunology
• Gastroenterology

Background:

• Gastrointestinal (GI) infections and associated dysbiosis can impact immune checkpoint inhibitor (ICI) efficacy.
• These infections may increase the risk of adverse events like colitis during ICI therapy.
• The influence of pre-ICI GI infections on immune-mediated colitis (IMC) and survival requires investigation.

Purpose of the Study:

• To explore the impact of GI infections preceding ICI therapy on the incidence and severity of IMC.
• To assess the effect of prior GI infections on patient survival during ICI treatment.

Main Methods:

• Retrospective review of patients receiving ICIs from January 2010 to February 2024 who developed IMC.
• Screening for IMC and prior GI infections using clinical symptoms and stool tests.
• Collection of demographic, IMC, and GI infection-related clinical data.

Main Results:

• 3.0% of patients (34/1132) had GI infections before ICI therapy, most commonly Clostridioides difficile.
• The incidence of IMC was significantly higher in patients with prior GI infections (8.7%) compared to those without (5.1%).
• Prior GI infection was independently associated with a 1.6-fold increased risk of mortality in patients receiving ICIs.

Conclusions:

• This study is the first to link pre-ICI GI infection to IMC incidence and survival outcomes.
• Prior GI infection increases the incidence of IMC in patients undergoing ICI therapy.
• Pre-existing GI infections are associated with a higher risk of mortality for patients receiving ICIs.