The results showed that HSP90B1 was significantly correlated with the immune microenvironment in BLCA, including “The human immune response to tuberculosis,” “T cell signal transduction,” “PD1 signalling” and “Cancer immunotherapy by PD1 blockade.” Enrichment analysis also showed that HSP90B1 was closely related to PD1, which was used as a prognostic marker for immunotherapy in BLCA. The gene discussed is PDCD1; the disease is tuberculosis.