High-dose therapy with autologous haemopoietic stem cell support for Waldenstrom's macroglobulinaemia

Standard doses of alkylating agents or purine analogues effect response rat es of up to 50% in Waldenstrom's macroglobulinaemia (WM) however complete r esponses are infrequent and there are no cures. We have evaluated the feasi bility, safety and efficacy of high-dose chemotherapy with peripheral blood stem cell support in six patients aged 45-69 years (median 51.5) with WM: four patients relapsed after prior therapy inclusive of purine analogues an d two patients proceeded with transplant after minimal therapy. Four patien ts mobilized adequate numbers of stem cells; however, two patients with mor e extensive fludarabine therapy failed to mobilize and required a second at tempt at stem cell collection. Five patients were treated with melphalan 20 0 mg/m(2), including one patient who received tandem transplants and one pa tient who received melphalan 140 mg/m2 with added total body irradiation (T BI), There eras no treatment-related mortality and non-haematological toxic ities were manageable. Engraftment was prompt except in one patient with ex tensive prior use of fludarabine. All the six patients achieved at least pa rtial response (PR), including one who achieved complete response (CR), Fiv e patients are alive and four are event-free at 52+, 15+, 12+ and 2+ months post transplant. This pilot study suggests safety and efficacy of high-dos e therapy in WM and suggests that the peripheral blood stem cells should pr eferably be procured prior to extensive use of purine analogues.