Checkpoint inhibition in macroglobulinaemia

Waldenström macroglobulinaemia (WM) is a unique, cluster of differentiation (CD) 20+ B-cell malignancy, with a characteristic immunoglobulin M-secreting lymphoplasmacytic bone marrow infiltrate that is bolstered by a highly supportive microenvironment, including upregulated programmed death 1 expression. However, the impact of checkpoint inhibition in WM is unclear. Commentary on: Kothari et al. PembroWM: A phase II trial to investigate the safety and efficacy of rituximab and pembrolizumab in relapsed/refractory Waldenström's macroglobulinaemia. Br J Haematol 2024; 205:2273-2281.