Detection of malignant B cells in peripheral blood stem cell collections after chemotherapy in patients with multiple myeloma.
Autologous transplantation after high-dose chemo or radiotherapy is now frequently used for the treatment of patients with multiple myeloma (MM). The collection of peripheral blood stem cells (PBSC) has a theoretical advantage over autologous bone marrow collection as the malignant plasmacytic contamination is believed to be lower. However, the extent of B cell contamination in PBSC has not been extensively investigated. Using an immunoglobulin heavy chain gene 'fingerprinting' technique at diagnosis and during apheresis after one cycle of chemotherapy we detected a monoclonal population in 44% of PBSC samples (9 positives in 22 studied). There was no correlation between contamination and sex, age, Durie and Salmon classification, C-reactive protein and albumin. A significant correlation was observed with beta 2 microglobulin serum level (P = 0.02). Twenty one patients were grafted and up to the present, with a mean follow-up of 12 months, 6 patients have relapsed including 4 patients with contaminating B cells. Our results suggest that PBSC contamination, defines a 'poor risk' group of patients, with poor prognosis. However, we could not exclude reinitiation of the disease by plasmacyte stem cells after grafting.
Dreyfus
F
F
Department of Haematology and Blood Bank, Hôpital Cochin, Paris.
Ribrag
V
V
Leblond
V
V
Ravaud
P
P
Melle
J
J
Quarre
M C
MC
Pillier
C
C
Boccaccio
C
C
Varet
B
B
D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001402:B-Lymphocytes / Q000276:immunology / Q000473:pathology*; D002999:Clone Cells; D003131:Combined Modality Therapy; D016172:DNA Fingerprinting; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007136:Immunoglobulins / Q000235:genetics / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood* / Q000628:therapy
D007136:Immunoglobulins