PDCD1 and hepatocellular carcinoma: In our study using 16S rRNA gene amplicon sequencing, we discovered higher intestinal microbial diversity indices (Chao1, Ace, and Shannon) in group T compared to group U. Additionally, the Simpson index was lower in group T. This indicates that the α-diversity of intestinal microorganisms was increased in patients with HCC after receiving triple therapy of local therapy combined with lenvatinib and PD-1 inhibitors, compared to patients with primary untreated HCC.