High-Dose Chemotherapy and Stem Cell Transplant in Treating Patients With Newly Diagnosed Stage I, Stage II, or Stage III Multiple Myeloma

RATIONALE: Drugs used in chemotherapy, such as melphalan, use different ways to stop cancer cells from dividing so they stop growing or die. Stem cell transplant using stem cells from the patient may be able to replace immune cells that were destroyed by chemotherapy used to kill cancer cells. Giving colony-stimulating factors, such as G-CSF or pegfilgrastim, helps stem cells move from the bone marrow to the blood so they can be collected. It is not yet known which regimen is more effective in treating multiple myeloma. PURPOSE: This randomized phase II trial is studying how well high-dose chemotherapy followed by stem cell transplant works in treating patients with newly diagnosed stage I, stage II, or stage III multiple myeloma.