Inactivating BTK mutations in large B-cell lymphoma in a real-world cohort: Strong correlation with BCL2 translocation.

Inactivating mutations in Bruton's tyrosine kinase (BTK) in patients with follicular lymphoma (FL) have recently been reported. These mutations were found in BTK inhibitor-treatment naïve patients. Here, we report the BTK mutation status in a real-world cohort of patients with non-Hodgkin lymphoma. We found primary BTK mutations in 7.7% of patients with large B-cell lymphoma (LBCL) and in 14.1% of patients with FL. All patients with BTK-mutated LBCL were BCL2 translocation positive, and the correlation between BCL2 translocation and BTK mutation persisted even when patients with known transformation from FL were excluded.