Primary systemic amyloidosis (AL) is characterized by widespread deposition of amyloid fibrils, derived from monoclonal immunoglobulin light chains as a result of a clonal plasma cell dyscrasia. In the last decade, high-dose melphalan and autologous stem cell transplantation (HDM/SCT) has been shown to induce hematologic and clinical remissions and prolong survival in patients with AL amyloidosis. Moreover, the treatment outcomes following HDM/SCT are related to whether or not a complete hematologic response, defined as disappearance of the underlying monoclonal gammopathy from serum and urine by immunofixation electrophoresis and of clonal plasma cell dysrasia by bone marrow biopsy, is achieved. The median survival of patients who achieve a hematologic complete response (CR) is greater than 8 years compared to 5.2 years for those who do not achieve a CR. Experience with tandem cycles of high-dose chemotherapy in multiple myeloma have shown that hematologic CR increases following tandem cycles of treatment from 24% to 43%.