Relapsed multiple myeloma.

The treatment of relapsed multiple myeloma remains a challenge for clinicians. Most salvage therapies result in transient responses, with median survival from relapse ranging from 6 to 18 months. No randomized trials comparing salvage therapies have been performed. In the absence of a "gold standard" salvage therapy, relapsed patients should be considered for clinical trials. In light of the recent observation that thalidomide alone brings about a 30% to 35% response rate with manageable toxicities, this is the most promising single agent available to treat relapsed disease. The maximum effective dose appears to be 400 mg/d; virtually all responses are evident within 2 months of starting therapy. Combination therapy of thalidomide with pulse dexamethasone or other chemotherapeutic agents has shown promise in pilot trials. Even with thalidomide-responsive disease, the response duration is brief, ranging from 3 to 6 months. Therefore, the authors recommend that patients under the age of 78 years who have acceptable physiologic organ function, chemotherapy-sensitive disease, third-party financial coverage, and adequate hematopoietic stem cells be considered for high-dose therapy with autologous hematopoietic stem cell transplant. High-dose therapy with hematopoietic stem cell transplant provides the highest response rate, response duration, and survival compared with historical controls treated with conventional therapy. Patients under the age of 70 years who have human leukocyte antigen-compatible donors should be considered for immune-based therapy using nonmyeloablative preparative regimens with allogeneic hematopoietic stem cell transplant.