Clinical Outcomes in t(4;14) Multiple Myeloma: A Chemotherapy-Sensitive Disease Characterized by Rapid Relapse and Alkylating Agent Resistance

Abstract
Purpose To determine whether primary drug resistance or rapid relapse explains the poor prognosis seen in t(4;14)-positive multiple myeloma (MM). Patients and Methods A total of 131 patients treated with high-dose therapy (HDT) were assessed, of whom 19 were t(4;14) positive. We examined the presentation features, chemotherapy responsiveness at presentation and to salvage therapies at relapse, and overall survival outcomes. Results t(4;14)-positive patients had a predominance of the immunoglobulin A isotype (52.6%) but otherwise baseline characteristics were indistinguishable. After treatment with vincristine, doxorubicin, and dexamethasone or dexamethasone alone, 17 (89.7%) of the 19 patients achieved a partial response and 11 patients (57.9%) demonstrated an additional 50% reduction in paraprotein after HDT. Thus, t(4;14)-positive patients are chemotherapy sensitive; however, early progression was common, with 26% of patients progressing before HDT and a median progression-free survival after HDT of onl...