title: Late-onset neutropenia in patients treated with rituximab for non-Hodgkin's lymphoma.
abstract: Late-onset grade 4 neutropenia occurred in 3 (5.6%) of 54 non-Hodgkin's lymphoma patients treated with rituximab between September 2001 and March 2004. Neutropenia appeared 5 to 25 weeks after administration of cytotoxic agents in combination with rituximab and recurred 4 and 17 weeks after the first onset in 2 patients. Five episodes occurred in a total of 332 cycles of rituximab therapy. Bone marrow findings at the time of late-onset neutropenia showed neutrophil maturation arrest with or without reversible myeloid dysplasia in 3 episodes and selective depletion of the myeloid series in 1 episode. Neither circulating immune complexes nor antineutrophil antibodies were detected during the 3 episodes that we evaluated. Bone marrow cells stained CD8- and CD57-. Late-onset neutropenia resolved 5 to 7 days after granulocyte colony-stimulating factor therapy was started. Further studies are needed to determine how rituximab functions and to identify appropriate countermeasures.
authors.affiliation: First Department of Internal Medicine, Gifu University Graduate School of Medicine, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Fukuno
authors.forename: Hisashi
authors.initials: H
authors.lastname: Tsurumi
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Ando
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Kanemura
authors.forename: Hideko
authors.initials: H
authors.lastname: Goto
authors.forename: Shinobu
authors.initials: S
authors.lastname: Tanabashi
authors.forename: Kiyonao
authors.initials: K
authors.lastname: Okamoto
authors.forename: Hisataka
authors.initials: H
authors.lastname: Moriwaki
mesh_terms: D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects*; D058846:Antibodies, Monoclonal, Murine-Derived; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000009:adverse effects; D001853:Bone Marrow / Q000473:pathology; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000139:chemically induced* / Q000188:drug therapy* / Q000473:pathology; D009504:Neutrophils / Q000473:pathology; D011994:Recombinant Proteins; D000069283:Rituximab; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D000069283:Rituximab