Ibrutinib (PCI-32765) in Waldenstrom's Macroglobulinemia

Patients in this research study will receive up to 40 cycles of treatment. Each treatment cycle lasts 4 weeks. Patients will take PCI-32765 by mouth, once a day in the morning. During each cycle patients will be asked to visit the clinic for scheduled tests and exams and to receive a supply of PCI-32765 to take at home every day. Patients will visit the clinic on the first day of each of the first 3 cycles, and then just once at the beginning of every three cycles. During study visits, patients will have a physical exam where they will be asked questions about their general health and specific questions about any problems that they might be having and any medications they may be taking. Patients will have blood tests to see how their disease is responding to the study treatment and how they are tolerating the study drug. Patients may also have CT scans of the chest, abdomen and pelvis as well as a bone marrow aspirate and biopsy. If a patient's disease stays the same or is helped, he/she will continue to get study treatment. If disease worsens, he/she will be taken off study treatment at that time. After completion of the treatment and as part of standard of care, follow-up tests will include a physical exam, review of symptoms and medications, blood tests, bone marrow aspirate and biopsy, CT scans of the chest, abdomen and pelvis. The investigators would like to continue to monitor progress by following-up every three months for up to two years after completion of study treatment or until next treatment, whichever comes first.