Comparing two ways of collecting stem cells to improve treatment of multiple myeloma

This study looked at two different ways of getting stem cells from the blood to improve the treatment of patients with multiple myeloma (MM). This study showed that the use of cyclophosphamide (CTX; Cytoxan) with granulocyte-colony stimulating factor (G-CSF; Neupogen) had the best outcomes.

MM is the second most common blood cancer in the USA. Survival rates have improved in the past 15 years thanks to advancements in MM treatment and autologous stem cell transplantation (ASCT). ASCT is a process where the patient’s own stem cells are taken from their blood. 

Getting stem cells into the blood and collecting a lot of these cells are two required processes for patients with MM undergoing ASCT. CTX and a protein called granulocyte-colony stimulating factor (G-CSF) or G-CSF on its own are the standard ways of getting stem cells. CTX and G-CSF to get stem cells have been used for years. However, this technique has been questioned because of side-effects noted by patients receiving this treatment. Trying G-CSF on its own reduced the harmful reaction to chemotherapy. It is important to compare the safety and effectiveness of G-CSF alone or in combination with CTX for the collection of stem cells in patients with MM undergoing ASCT.

This study analyzed the results of 18 other studies with a total of 2,770 patients with MM. Patients received either CTX and G-CSF or G-CSF alone to collect stem cells for ASCT.

11 studies with 1,619 patients showed that CTX and G-CSF combination was 2.8 times more successful at getting stem cells than using G-CSF on its own. 9 studies with 969 patients underwent ASCT after getting stem cells. Patients given CTX and G-CSF after ASCT were 41% more likely to respond to this treatment compared to G-CSF alone.

Patients in the CTX and G-CSF group were 65% more likely to survive at 3 years without any complications related to the MM than those getting G-CSF alone. However, patients in the CTX and G-CSF combination group were 26.49 times more likely to need hospital admission during stem cell collection compared to G-CSF alone. These patients also had significantly more fever as a side effect compared to those who had G-CSF alone.

This study showed that CTX and G-CSF combination was the best way of getting stem cells for ASCT in patients with MM.

The chosen studies that this study focused on were small-scale clinical trials. More large-scale clinical trials are needed in the future to give a better global representation.