Trial of High Dose Melphalan/Stem Cell Transplant With or Without Bortezomib

This study seeks to enroll patients with AL amyloidosis who have been recommended for standard treatment with high-dose melphalan and stem cell transplant. Standard treatment for this disease is high-dose melphalan and stem cell transplant. The purpose of this study is to compare the safety and effectiveness of standard treatment with high-dose melphalan and stem cell transplant, compared with investigational bortezomib when used in combination with standard treatment with high-dose melphalan and stem cell transplant for AL amyloidosis. Patients enrolled in this study will receive either standard treatment with high-dose melphalan and stem cell transplant, or investigational bortezomib used in combination with standard treatment with high-dose melphalan and stem cell transplant.