Integrating molecular subtype and CD8+ T cells infiltration to predict treatment response and survival in muscle-invasive bladder cancer

Background Luminal and Basal are the primary intrinsic subtypes of muscle-invasive bladder cancer (MIBC). The presence of CD8 + T cells infiltration holds significant immunological relevance, potentially influencing the efficacy of antitumor responses. This study aims to synergize the influence of molecular subtypes and CD8 + T cells infiltration in MIBC. Methods This study included 889 patients with MIBC from Zhongshan Hospital, The Cancer Genome Atlas, IMvigor210 and NCT03179943 cohorts. We classified the patients into four distinct groups, based on the interplay of molecular subtypes and CD8 + T cells and probed into the clinical implications of these subgroups in MIBC. Results Among patients with Luminal-CD8 + T high tumors, the confluence of elevated tumor mutational burden and PD-L1 expression correlated with a heightened potential for positive responses to immunotherapy. In contrast, patients featured by Luminal-CD8 + T low displayed a proclivity for deriving clinical advantages from innovative targeted interventions. The Basal-CD8 + T low subgroup exhibited the least favorable three-year overall survival outcome, whereas their Basal-CD8 + T high counterparts exhibited a heightened responsiveness to chemotherapy. Conclusions We emphasized the significant role of immune-molecular subtypes in shaping therapeutic approaches for MIBC. This insight establishes a foundation to refine the process of selecting subtype-specific treatments, thereby advancing personalized interventions for patients.