BTK and marginal zone lymphoma: Bruton Tyrosine Kinase (BTK) inhibition has been proven effective in patients with relapsed MZL with response rates between 53% and 68% in several prospective phase II trials with ibrutinib (NCT01980628), acalabrutinib (NCT02180711), and zanubrutinib (NCT03846427), respectively.32, 33, 34, 35