The following is a summary of “Intratumoral Escherichia Is Associated With Improved Survival to Single-Agent Immune Checkpoint Inhibition in Patients With Advanced Non–Small-Cell Lung Cancer,” published in the July 2024 issue of Oncology by Elkrief et al.
The role of the intratumoral microbiome in immune checkpoint inhibitor (ICI) effectiveness in patients with non–small-cell lung cancer (NSCLC) is unclear. Preclinical data suggest intratumoral *Escherichia* may create a proinflammatory tumor environment and reduce metastases.
Researchers conducted a retrospective study assessing if intratumoral *Escherichia* correlates with outcomes in patients with NSCLC treated for ICI.
They analyzed the intratumoral microbiome in 958 patients with advanced NSCLC treated with ICI by mapping next-generation sequencing reads to bacterial genomes. Filtered potential contaminants using no-template controls (n = 2,378) and performed univariable and multivariable analyses to assess OS. Validation occurred in an external cohort of 772 patients. Escherichia detection was confirmed by fluorescence in situ hybridization (FISH) and transcriptomic analysis.
The results showed intratumoral *Escherichia* detection was associated with longer OS in patients treated with single-agent ICI (16 vs. 11 months; HR, 0.73 [95% CI, 0.59 to 0.92], P=.0065) but not with chemoimmunotherapy. After adjusting for prognostic factors like PD-L1 expression (P=.023), the association remained significant in multivariable analysis. In an external validation cohort of 772 patients, the association with improved OS was confirmed in univariable and multivariable analyses for single-agent ICI but not chemoimmunotherapy. The FISH confirmed *Escherichia* within tumor cells, and transcriptomic profiling indicated immune cell infiltration in *Escherichia-positive samples.
They concluded that intratumoral *Escherichia* was linked to better survival outcomes in patients with NSCLC getting treatment of single-agent ICI.
Source: ascopubs.org/doi/10.1200/JCO.23.01488
