Targeting the BTK in WM cells by BTK inhibitors has changed the treatment landscape in WM: in the pivotal phase II study 63 symptomatic relapsed patients with Waldenström’s macroglobulinemia received Ibrutinib at a daily oral dose of 420 mg until disease progression or the development of unacceptable toxicity. Here, BTK is linked to Waldenstrom macroglobulinemia.