DCEP (Dexamethasone, Cyclophosphamide, Etoposide, Cisplatin) Followed by High-Dose G-CSF Is a Highly Efficient and Safe Regimen for Stem Cell Mobilization for Multiple Myeloma.

High dose chemotherapy with autologous stem cell rescue remains a standard therapy for multiple myeloma patients who can tolerate it. A mobilizing regimen for multiple myeloma should ideally allow for a high yield of CD34⁺ cells, provide anti-myeloma activity, be well tolerated, and have predictable kinetics regarding initiation of collection of stem cells. Higher numbers of infused autologous CD34⁺ cells allow for more rapid engraftment and lower incidence of transplant-related morbidity and mortality. The goal for patients with myeloma is to harvest enough CD34⁺ cells to provide at least two autologous transplants. Previous mobilization regimens utilized G-CSF alone or high-dose cyclophosphamide with G-CSF. However, high-dose cyclophosphamide (4–7g/m²) has only modest efficacy against myeloma and is associated with significant morbidity and up to 1–2% treatment-related mortality. DCEP (dexamethasone, cyclophosphamide, etoposide, cisplatin) is a well established regimen with good efficacy as salvage treatment for myeloma. Additionally, the use of DCEP with G-CSF for mobilization in myeloma has previously been reported to provide an average yield of approximately 6x10⁶ CD34⁺ cells. We report our experience with DCEP and high-dose G-CSF in mobilizing 88 multiple myeloma patients since 2006. Our regimen consisted of 40 mg dexamethasone IV over 15 minutes x 4 days, cyclophosphamide 500 mg/m², etoposide 40 mg/m² (capped at 75 mg), and cisplatin 15 mg/m² (capped at 25 mg), all continuous IV infusions over 24h x 4 days, with G-CSF starting 24–48h after completion of chemotherapy, administered SQ at 5 mcg/kg x 6 days followed by 10 mcg/kg daily until pheresis is completed. Over 80% of our patients were ready to initiate collection on day 14. Our goal for collection is 10–12x10⁶ CD34⁺ cells to allow for two or three transplants using at least 4x10⁶ CD34⁺ cells per transplant. Yields were excellent with a mean yield of 27x10⁶ CD34⁺ cells, with a range of 7.3–130.5x10⁶ CD34⁺ cells. 37/88 (42%) of patients required only one day of pheresis, with a mean yield of 34x10⁶ CD34⁺ cells. 38/88 (43%) of patients required two days of pheresis. Only 15% of patients required more than two days of pheresis. Only 3 patients yielded fewer than 10x10⁶ CD34⁺ cells (3%), and none yielded fewer than 5x10⁶ CD34⁺ cells. In conclusion, this regimen is highly efficacious, offers excellent stem cell yields and predictable collection kinetics, can be administered on an outpatient basis, and is safe and well tolerated.