We report here the transplantation of extensively purified "mobilized" peripheral blood CD34Thy-1 hematopoietic stem cells from 22 patients with recurrent or metastatic breast cancer. Patients were mobilized with either high-dose granulocyte colony-stimulating factor (G-CSF) alone or cyclophosphamide plus G-CSE Median purity of the stem cell product at cryopreservation was 95.3% (range, 91.1%-98.3%), and viability was 98.6% (range, 96.5%-100%). After high-dose chemotherapy with carmustine, cisplatin, and cyclophosphamide, CD34+Thy-1 cells at a median dose of 11.3 x 10(5) per kilogram (range, 4.7-163 x 10(5) per kilogram) were infused. No infusion-related toxicity was observed. Neutrophil recovery was prompt, with median absolute neutrophil count >500/microL by day 10 (range, 8-15 days) and >1000/microL by day 11 (range, 8-17 days). Median platelet recovery (>20,000/microL) was observed by day 14 (range, 9-42 days) and >50,000/microL by day 17 (range, 11-49 days). Tumor cell depletion below the limits of detection of a sensitive immunofluorescence-based assay was accomplished in all patients who had detectable tumor cells in apheresis products before processing. Although CD4+ T-cell reconstitution was slow, no unusual infections were observed. Neither early nor late graft failure was observed, and no patient required infusion of unmanipulated backup cells. At a median follow-up of approximately 1.4 years and a maximum follow-up of 2.5 years, 16 of the 22 patients remain alive, with 9 free of disease progression, and have stable blood counts. In summary, highly purified CD34+Thy-1+ cells used as the sole source of the hematopoietic graft result in rapid and sustained hematopoietic engraftment.

Central nervous system (CNS) involvement by non-Hodgkin's lymphoma (NHL) carries a poor patient prognosis whether it occurs as a primary site of disease or secondarily in patients with systemic disease. In a group of 481 patients undergoing high-dose therapy with hematopoietic cell transplantation (HCT) for NHL, 15 patients (3.1%) were identified with CNS involvement. Two patients had primary CNS lymphoma, and 13 had secondary disease. All patients received intrathecal chemotherapy, and 13 received CNS radiotherapy before transplantation. Fourteen patients received systemic chemotherapy. At the time of transplantation, both patients with primary CNS lymphoma and 8 patients with secondary disease had achieved a complete response, 3 patients had achieved a partial response, 1 had failed induction therapy, and 1 had progression of CNS disease before high-dose therapy. Fourteen patients received carmustine, etoposide, and cyclophosphamide as the preparative regimen, and 1 patient received fractionated total body irradiation instead of carmustine. The 2 patients with primary CNS lymphoma were alive and free of disease, 1 at 1,085 days after HCT and 1 at 3,704 days after HCT. The actuarial 5-year event-free survival (EFS) was 46% +/- 26%, and overall survival (OS) was 41% +/- 28%. The median EFS and OS were 2.2 and 1.5 years, respectively. Three patients experienced symptomatic memory loss or intellectual decline after therapy, 1 patient developed paraplegia, and 1 patient had a thrombotic stroke 20 months after HCT. Despite treatment-related toxicities, 7 patients responding to quality-of-life questions at approximately 1 year after HCT gave their overall quality of life a median rating of 9 out of a possible 10 (range, 6-10). High-dose therapy with autologous HCT can produce extended EFS in patients with secondary CNS lymphoma and possibly in those with primary CNS NHL.

No abstract