The t(11;14)(ql3;q32) chromosomal translocation is associated with several B-cell lymphoproliferative disorders and is thought to result in upregulation of expression of PRAD1/cyclin D1 protooncogene. A patient with multiple myeloma of IgG κ-type with t(11;14)(q13;q32) is now shown to overexpress PRAD1. The clinical stage of the disease was advanced (IIIA), with a myeloma cell count of 94.6% in the bone marrow. Chromosomal analysis of bone marrow cells showed t(11;14)(q13;q32) in five of 20 metaphases as well as other karyotypic features. Northern blot analysis of RNA prepared from myeloma cells revealed overexpression of PRAD1. Multiple myeloma with t( 11; 14)(q 13;q32) has been associated with an aggressive clinical course. Although neither myeloma cells in the peripheral blood nor extramedullary lesions were apparent in the present patient, the myeloma was refractory to several chemotherapeutic regimens from the beginning. Detection of PRAD1 expression may offer an easier alternative to cytogenetic analysis in myeloma and is a potentially useful indicator of a poor prognosis.