Bone marrow CD34+ cell count is predictive for adequate peripheral progenitor cell collection.

Several studies have investigated the influence of clinical and biological variables on mobilisation of peripheral blood progenitor cells (PBPCs). The aim of this study was to evaluate the role of steady-state bone marrow (BM) CD34+ cells as a predictive parameter of PBPC yield. We studied 90 patients with multiple myeloma (MM) (41 patients), non-Hodgkin's lymphoma (NHL) (25 patients) or acute myeloid leukaemia (AML) (24 patients), mobilised with chemotherapy and growth factor. The median time from first treatment to mobilisation was 5 months. Only one patient was previously exposed to alkylating agents. The median BM CD34+ count at mobilisation was 833 microl(-1) (range: 1.4-15.540) corresponding to 1.51% of mononuclear cells (range: 0.02-8.6). Sixty-six patients (73%) reached the optimal target of 4 x 10(6) kg(-1) CD34+ cells with 1 (18 patients), 2 (42 patients) or 3 leukaphereses (6 patients). Eleven patients (12%) mobilised less than 4 x 10(6) kg(-1) CD34+ cells and 13 (15%) failed mobilisation. Among the laboratory and clinical parameters evaluated at the time of mobilisation, only BM CD34+ count was a predictive factor for adequate collection (P = 0.04), particularly in MM patients (P = 0.003). In this setting, a BM concentration of CD34+ cells lower than 66 microL(-1) was associated with a higher probability of inadequate collection.

A combination of dexamethasone, cyclophosphamide, etoposide, and cisplatin is less toxic and more effective than high-dose cyclophosphamide for peripheral stem cell mobilization in multiple myeloma.

BACKGROUND AND OBJECTIVES: The purpose of this study was to compare the efficacy and toxicity of two regimens for peripheral blood stem cell (PBSC) mobilization in multiple myeloma (MM) patients. DESIGN AND METHODS: From 1995 to 2001, 116 patients were enrolled in two high-dose programs including autologous transplantation, adopting two mobilizing regimens: 61 patients were mobilized with high-dose cyclophosphamide (HD-Cy) at 4 g/m2 (group I), and 55 patients with DCEP (dexamethasone, cyclophosphamide, etoposide, and cisplatin) (group II), both followed by granulocyte colony-stimulating factor (G-CSF 5 mg/Kg/day) started 48 hours after chemotherapy. RESULTS: The median number of CD34+ cells harvested was similar in the two groups (5.9 vs 5.82x106 cells/kg). The target of at least 4x106 cells/kg was reached in a higher percentage of patients in the DCEP group (75 vs 59%) (p=0.05). The proportion of poor mobilizers (<2x106 CD34+ cells/kg) was 21% with HD-Cy and 13% with DCEP (P=NS). In group I, 10 patients (16%) required packed red cell transfusions, 5 patients (8%) platelet support, and the majority of patients (87%) had a neutrophil count below 500/mL, whereas none did so in group II (p=0.0009, p=0.01, p=0.0009, respectively). Neutropenia-related fever occurred in 18% of patients in group I versus 0% in group II (p=0.0005). WHO grade >II extra-hematologic toxicities (microhematuria, cystitis, infections) were seen in 8 patients (13%) of group I vs 0 in group II (p=0.007). INTERPRETATION AND CONCLUSIONS: DCEP is a better tolerated and more effective regimen than HD-Cy for peripheral stem cell mobilization in MM patients assigned to high-dose therapy programs.

Advantages of using thalidomide for the management of refractory myeloma patients.

A group of 11 heavily pretreated patients receiving low-dose thalidomide was compared with a similar group of 10 patients with refractory myeloma treated with a convention-al oral chemotherapy. This study shows that thalidomide is not only effective in controlling the neoplastic clone but more-over, thanks to its low toxicity, allows out-patient management of these subjects.