 Given the unsatisfactory results of standard chemotherapy regimens, new treatments are being explored for use in PBL.Bortezomib, a drug that inhibits proteasomes, has been used alone or in combination with radiation and/or CHOP, EPOCH, or THP-COP (pirarubicin, cyclophosphamide, vincristine, and prednisone) chemotherapy regimens to treat some scores of patients with newly diagnosed or relapsed PBL.The results of these exploratory studies have been at least modestly encouraging and provide strong support for further studies using more controlled conditions.