Evaluating the effectiveness and safety of etoposide combined with cytarabine plus G-CSF for stem cell mobilization in patients with multiple myeloma.

This study evaluated the effectiveness and safety of etoposide (Etopophos) combined with cytarabine (Cytosar-U) plus granulocyte colony-stimulating factor (G-CSF, Neupogen) in patients with multiple myeloma (MM) for stem cell mobilization. The data showed that etoposide combined with cytarabine plus G-CSF was safe and effective for the collection of stem cells for autologous stem cell transplantation (ASCT) in these patients.

MM is a type of cancer that comes from blood cells called plasma cells. Survival rates have improved in the past 15 years due to the advancements in treatment options and autologous stem cell transplantation (ASCT). ASCT involves transplanting healthy stem cells from the same patient. Getting stem cells into the blood and collecting a lot of these cells are two required processes for patients with MM undergoing ASCT.

Cyclophosphamide (CTX; Cytoxan) and G-CSF are the standard ways of getting stem cells for many years. However, this technique has been associated with side effects. Previous studies have shown that a new combination of etoposide plus G-CSF was effective in patients with MM. However, the effectiveness and safety of etoposide combined with cytarabine plus G-CSF, for the collection of stem cells in patients with MM undergoing ASCT are still unknown.

This study involved 128 patients with MM. 70 (54.7%) patients previously underwent induction treatment (treatment to kill and remove cancer cells) with lenalidomide (Revlimid). All patients received a combination of etoposide with cytarabine plus G-CSF for stem cell mobilization.

Overall, the average number of stem cells collected 28.23×10⁶ CD34+ cells/kg. All 128 patients achieved adequate collection (≥2×10⁶ CD34+ cells/kg), 121 (94.5%) patients achieved optimal collection for single ASCT (≥5×106 CD34+ cells/kg), and 114 (89.1%) patients achieved optimal collection for tandem ASCT (≥10×10⁶ CD34+ cells/kg). Tandem ASCT refers to two ASCT procedures performed within 6 months. 

Overall, 125 patients underwent ASCT as planned. The other 3 were still waiting in line to receive ASCT. 14 patients achieved a deep response (very good partial disappearance of the cancer or better) after stem cell mobilization. Previous treatment with lenalidomide did not significantly impair CD34+ cells collection.

The most common side effect was low white blood cell counts and low platelet counts. No severe infection or treatment-related deaths occurred.

This study concluded that etoposide combined with cytarabine plus G-CSF was safe and effective for the collection of stem cells in patients with MM.

This study looked back in time at medical records. The sample size was very small. This study only included patients treated at a single medical institution in China.