TCF7 and melanoma: scRNA-seq can predict the prognosis of ICB therapy by analyzing the gene expression characteristics of TIBs: in neoadjuvant ICB treatment of melanoma, responders have higher CD20 + B cell density, tertiary lymphoid structures (TLS) and TLS to tumor area ratio; scRNA-seq can identify B cell-related genes and other immune cell genes in TLS-rich melanoma for prognosis prediction; TCF7 + naive/memory T cells increase in B cell-enriched tumors, suggesting that B cell-rich TLS are critical to shaping the immune microenvironment.