Autologous Stem Cell Rescue With CD133+ Selected Hematopoietic Progenitor Cells in Patients With High-Risk Neuroblastoma

Researchers want to learn if a CD133+ selected autologous stem cell transplant can help to control the disease in patients with high-risk neuroblastoma. After your cells are collected, they will be treated in the cell processing lab using the CliniMACS device. This device will separate out the CD133+ cells. These selected cells will then be given back to you on the day of transplant.

If you are found to be eligible to take part in this study, you will have a small plastic tube placed in the collar bone area or the femoral vein (groin area). This is called a central venous catheter (CVC). You will sign a separate consent form for the CVC placement and the general anesthesia that is given. There may be several weeks between the collection of stem cells and the reinfusion of these cells after high-dose chemotherapy. If the CVC is placed in the femoral vein, the CVC will be removed after the stem cells are collected and a new CVC will be placed in the collar bone before you are admitted for the stem cell transplant. The CVC will be used for chemotherapy, fluids, blood products, stem cells, and other medications. The CVC will remain until it is no longer needed (usually 2-3 months).

To help move the needed stem cells from your bone marrow to your blood, a drug called granulocyte colony-stimulating factor G-CSF (filgrastim) will be injected under the skin. These injections may be given once a day for Days 2-7. You or your caregiver will be taught how to give the injections at home. After 2 days of filgrastim injections, a blood sample (about 4 teaspoons each time) will be drawn each day until you begin leukapheresis. This blood test is used to check the number of stem cells and to watch for possible side effects. You will then be instructed to either continue with the daily injections or stop. When the number of stem cells in the blood is high enough, you will go to the MD Anderson Apheresis Unit to have your stem cells collected.

The procedure to collect your stem cells is called leukapheresis. It is similar to donating platelets to a blood bank. For this procedure, the stem cells will be removed from the blood through the CVC, and the remaining blood will be given back to you through the CVC. You will have one leukapheresis procedure per day, for 1-5 days in a row, until enough stem cells are collected for the transplant. "Back-up" cells (extra cells collected during the leukapheresis procedure) will also be collected. These cells will be stored in the cell processing lab and may given back to you later if your white cell count does not recover. Each leukapheresis procedure takes about 4-6 hours. This research study will use the CliniMACS device to process the blood and separate the cells needed for transplantation. Researchers will test a small sample of the collected cells to see if any tumor cells that might be present in the blood before using the CliniMACS device are no longer present in the processed blood after using the device.

Carboplatin and etoposide are designed to interfere with the growth of cancer cells by stopping cell division, and melphalan is designed to damage the DNA (the genetic material) of cells. The combination of carboplatin, etoposide, and melphalan causes a large amount of bone marrow cells to die, which stops blood cells from being produced as normal. In order to try to restart the production of blood cells, an autologous stem cell transplant is often performed. For an autologous transplant, stem cells are removed from the blood. Usually when stem cells are collected, they are either given back to the patient as collected, or else a smaller group of cells that have a certain "marker" on their cell surface is selected (separated out) before being given back to the patient. The CliniMACS device is a machine that processes blood and separates the cells needed for transplantation. The CliniMACS device is designed to select stem cells with a different marker on the cell surface than is normally selected. The marker is called CD133+, and researchers believe that transplanting cells that have this marker will make the infused cells less likely to be contaminated with neuroblastoma cells, compared to the standard method of cell selection.