title: Rapidly cycled courses of high-dose alkylating agents supported by filgrastim and peripheral blood progenitor cells in patients with metastatic breast cancer.
abstract: Our purpose was to determine the feasibility of a regimen of multiple, rapidly cycled courses of high-dose alkylating agents, including paired courses of escalating doses of thiotepa, supported by peripheral blood progenitor cells and filgrastim, in patients with responding stage IV breast cancer. The regimen consisted of two courses of cyclophosphamide (3.0 g/m2/course) followed by two courses of thiotepa (500-700 mg/m2/course). All courses were supported by filgrastim. Leukaphereses were performed after each cyclophosphamide course to harvest peripheral blood progenitors (PBPs) for use as rescue following thiotepa administration. The planned interval for all courses was 14 days. Forty-two patients were enrolled. Thirty-eight received all four courses, and four did not receive the second thiotepa cycle due to poor PBP mobilization. The maximum dose of thiotepa that was administered was 700 mg/m2 x 2. At this dose, one patient developed encephalopathy, which resolved over several weeks. The median number of days to an absolute neutrophil count of 0.5 x 10(9)/liter after PBP reinfusion for cycles 1 and 2 of thiotepa were 9 (range, 7-16) and 9 (range, 8-13) days, respectively. The corresponding values for platelet recovery to >20 x 10(9)/liter were 11 (range, 8-39) and 12 (range, 10-28) days, respectively. There were no treatment-related deaths. Hospitalization was required following 28 of 84 cyclophosphamide courses and 76 of 80 thiotepa courses. Four patients developed grade III-IV mucositis. The median interval between courses of treatment was 15 (range, 13-29) days. Of 19 patients who entered the protocol with measurable disease in partial response from prior therapy, 8 (42%) achieved complete response following the high-dose therapy. Nine (21%) of 42 remain progression free at a median follow-up of 28 (range, 20-32) months. Therefore, we concluded that the administration of multiple, rapidly cycled courses of high-dose alkylating agents is feasible.
authors.affiliation: Breast and Gynecologic Cancer Medicine Service, Division of Solid Tumor Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
authors.forename: L
authors.initials: L
authors.lastname: Vahdat
authors.forename: G
authors.initials: G
authors.lastname: Raptis
authors.forename: D
authors.initials: D
authors.lastname: Fennelly
authors.forename: N
authors.initials: N
authors.lastname: Hamilton
authors.forename: L
authors.initials: L
authors.lastname: Reich
authors.forename: A
authors.initials: A
authors.lastname: Tiersten
authors.forename: M
authors.initials: M
authors.lastname: Harrison
authors.forename: C
authors.initials: C
authors.lastname: Hudis
authors.forename: M
authors.initials: M
authors.lastname: Moore
authors.forename: T J
authors.initials: TJ
authors.lastname: Yao
authors.forename: Larry
authors.initials: L
authors.lastname: Norton
authors.forename: John
authors.initials: J
authors.lastname: Crown
mesh_terms: D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage* / Q000009:adverse effects; D001943:Breast Neoplasms / Q000188:drug therapy*; D003131:Combined Modality Therapy; D003520:Cyclophosphamide / Q000008:administration & dosage / Q000009:adverse effects; D005240:Feasibility Studies; D005260:Female; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D019650:Hematopoietic Stem Cell Mobilization; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008875:Middle Aged; D011994:Recombinant Proteins; D013852:Thiotepa / Q000008:administration & dosage / Q000009:adverse effects
chemical_list: D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D003520:Cyclophosphamide; D013852:Thiotepa; D000069585:Filgrastim