Clinical and biological features of t(4;14) multiple myeloma: a prospective study.

The t(4;14) translocation, found in 15% of multiple myeloma (MM), indicates a poor prognosis. Clinico-biological features associated with this severe outcome and the impact of novel agents are unknown. We report a series of 102 consecutive patients with t(4;14) MM. The median age was 56 years. The isotype was IgA in 42%, and the median serum β(2)-microglobulin was 2.3 mg/L. FGFR3 expression was lacking in 20 (19%) cases. Monoclonal gammopathy of undetermined significance (MGUS) or smoldering MM (sMM) was found in 26 patients (25%). Seven (27%) became symptomatic in a median time of 9 months. Fifty-six of 76 patients with symptomatic MM received high-dose therapy (HDT). The overall response rate (ORR) was 93% (22% CR, 44% VGPR), and the median progression-free survival (PFS) was 12 months. Twenty-four (37%) patients experienced aggressive relapse. Post-second-line ORR was 51% and the median PFS was 7 months, with a trend for longer PFS in patients treated with a bortezomib-based regimen. Median overall survival after HDT was 31 months. t(4;14) is detected in patients with MGUS/sMM and this does not require immediate chemotherapy. Patients with t(4;14) MM have a high ORR after HDT, contrasting with a short PFS and aggressive relapses, and, despite novel agents, still have a poor prognosis.