Tertiary Lymphoid Structures in Non–Muscle-Invasive Bladder Cancer: Quality over Quantity

High tertiary lymphoid structure (TLS) density predicts favorable outcomes in several solid tumors but worse outcomes in bladder cancer, and the basis for this discrepancy is unclear. In this issue, Péricart and colleagues leverage en bloc resection of non-muscle-invasive bladder tumors to show that TLS accumulate without acquiring the features of productive antitumor immunity. The work reframes TLS in this setting as structures for which functional state, not abundance, dictates their contribution to tumor control. See related article by Péricart et al., p. XX.