HP and cancer: However, it is also worth noting that there were not found any statistically significant differences in the fecal zonulin (a biomarker of intestinal permeability [34]) concentration between study subgroups, and circulating cfmDNA showed a distinct composition from the stool microbiome (data not published), suggesting that the gut microbiota, which was found to be associated with clinical outcomes of ICIs in various cancer cohorts [6,7,8,9,10], was not the major source of circulating cfmDNA in our study.