BTK and marginal zone lymphoma: More recently, also trials using Bruton tyrosine kinase (BTK) inhibitors in patients with marginal zone lymphomas including MALT lymphoma have been performed.105 In an initial series using ibrutinib, 32/63 patients included suffered from MALT lymphoma, and in the overall cohort a response rate of 53% with an 18 months PFS of 62% was seen.106 An update published in 2020 showed an RR of 65% in the MALT lymphoma cohort.107 In this series, also biomarker testing was performed and available for 24 patients with MALT lymphoma.