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R S Negrin

Publications and source records attributed to R S Negrin.

At least 37 records · Page 2Linked to original sources

Pulmonary toxicity syndrome in breast cancer patients undergoing BCNU-containing high-dose chemotherapy and autologous hematopoietic cell transplantation.

We performed a retrospective review to investigate pulmonary toxicity syndrome (PTS) in a cohort of breast cancer patients undergoing BCNU-containing high-dose chemotherapy (HDC). Our aim was to characterize presentation, identify risk factors, determine outcome following therapy, and find any association with differences in survival. We reviewed the data of 152 patients with stage II or III or metastatic breast cancer treated with cyclophosphamide 5625 mg/m2, cisplatin 165 mg/m2, and BCNU 600 mg/m2 followed by autologous peripheral blood hematopoietic cell transplantation. During follow-up, PTS was diagnosed when the following criteria were met: (1) presentation with typical clinical symptoms of PTS, (2) an absolute carbon monoxide diffusion capacity (DLCO) decline of 10% compared with pre-HDC DLCO, and (3) no clinical evidence of active pulmonary infection. Patients were then treated with a course of corticosteroid therapy. The incidence of PTS for all 152 patients was 59%, with a median onset at 45 days (range, 21-149 days) post-HDC. The median absolute DLCO decrement was 26% (range, 10%-73%) at diagnosis of PTS. There was no significant correlation between patient age, stage of breast cancer, pre-HDC chemotherapy regimen, pre-HDC chest wall radiotherapy, tobacco use, prior lung disease, or baseline pulmonary function test results and the development of PTS. We did observe an interesting association between PTS and the development of a noncholestatic elevation of transaminases. Of PTS patients treated with prednisone therapy for a median of 105.5 days (range, 44-300 days), 91% achieved resolution of their PTS without pulmonary sequelae. At 3 years, the overall survival (OS) of stage II or III patients who developed PTS was 84% (95% confidence interval [CI], 73%-95%); of metastatic breast cancer patients with PTS, the OS was 58% (95% CI, 38%-78%). These values were not significantly different from those of patients who did not develop PTS (91% [95% confidence interval [CI], 81%-100%] and 53% [95% CI, 32%-74%], respectively). No significant differences in disease-free or event-free survival were observed between patients with and without PTS. The incidence of PTS in breast cancer patients treated with a BCNU-containing HDC regimen can be remarkably high. Treatment with a course of corticosteroid therapy is successful in the vast majority.

Adult↗

Favorable treatment outcome in non-Hodgkin's lymphoma patients with "poor" mobilization of peripheral blood progenitor cells.

Our purpose was to evaluate the outcome and costs of high-dose chemotherapy and autologous peripheral blood progenitor cell (PBPC) transplantation in patients with the inability to mobilize sufficient numbers of PBPCs to allow rapid engraftment after PBPC transplantation. We treated 172 consecutive non-Hodgkin's lymphoma (NHL) patients with cyclophosphamide and granulocyte colony-stimulating factor followed by apheresis to collect PBPCs. The cells were separated on a Percoll gradient and purged with monoclonal antibodies and complement. The patients were categorized as "good" mobilizers if a collection of > or =2 x 10(6) CD34+ cells/kg was obtained (n = 138, 80%) or "poor" mobilizers if <2 x 10(6) CD34+ cells/kg were obtained (n = 34, 20%). With a median follow-up of 3.5 years, there is no statistically significant difference in actuarial event-free survival, overall survival, or relapse for good mobilizers compared with poor mobilizers. However, there was a trend toward increasing nonrelapse, transplantation-related mortality of 11.8% for poor mobilizers versus 3.6% for good mobilizers (P = .08) and early death from all causes including relapse within 120 days (poor 20.6% versus good 8.7%, P = .06). The total cost for bone marrow transplantation-related care was significantly higher, at $140,264 for poor mobilizers versus $80,833 for good mobilizers (P = .0001). The population of patients with NHL who mobilize PBPCs poorly into the circulation have a higher cost for posttransplant support. However, there is no significant difference in relapse, event-free survival, or overall survival for such patients compared with those who mobilize PBPCs easily.

Adult↗

Four-cycle high-dose therapy with hematopoietic support for metastatic breast cancer: no improvement in outcomes compared with single-course high-dose therapy.

Multiple-cycle high-dose therapy with autologous hematopoietic progenitor cell (AHPC) support has been used to deliver dose-intensive therapy. We have used this approach as well as single-cycle high-dose therapy in treating patients with metastatic breast cancer. We present the outcomes of multiple-cycle high-dose therapies and compare them with those resulting from single-course high-dose therapies performed at a single institution. Fifty-five patients received 4 cycles of intensive chemotherapy with AHPC support. Three multicycle regimens were sequentially applied. Twenty patients were enrolled to receive 4 cycles of high-dose mitoxantrone, thiotepa, and cyclophosphamide. Nineteen subsequent patients received this regimen modified by the incorporation of paclitaxel. Sixteen patients received 2 cycles of high-dose melphalan, thiotepa, and paclitaxel and 2 cycles of mitoxantrone, thiotepa, and paclitaxel. The results of all 3 multiple-cycle therapies are compared with those of 55 contemporaneous patients with metastatic breast cancer who received a single course of high-dose cyclophosphamide and thiotepa or cyclophosphamide, cisplatin, and BCNU (carmustine) with hematopoietic cell rescue. Multiple-cycle therapy was associated with more infectious complications, increased transfusion requirements, and increased hospital admissions. However, there were no significant differences in outcomes between the groups. For 55 patients who received multiple-cycle therapy, the actuarial 3-year overall survival rate was 36% (95% confidence interval [CI] 23%-49%); freedom from progression and event-free survival were both 15% (CI 5%-25%). The median time to disease progression and median survival were 1.0 and 1.6 years, respectively. For the 55 patients who underwent a single course of high-dose therapy, the 3-year overall survival was also 36% (CI 18%-54%), whereas freedom from progression and event-free survival were both 19% (CI 7%-31%). The median time to progression and median survival were 0.8 and 2.2 years, respectively. Within the constraints of this patient population, the outcomes of 4 cycles of high-dose therapy with AHPC support were not superior to those resulting from single courses of high-dose therapy in the treatment of patients with metastatic breast cancer.

Adjuvants, Pharmaceutic↗

High-dose therapy with hematopoietic cell transplantation for patients with central nervous system involvement by non-Hodgkin's lymphoma.

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.

Actuarial Analysis↗

Toxicity of high-dose sequential chemotherapy and purged autologous hematopoietic cell transplantation precludes its use in refractory/recurrent non-Hodgkin's lymphoma.

We conducted a pilot study in 20 patients with high-risk or recurrent/refractory non-Hodgkin's lymphoma (NHL) using high-dose sequential chemotherapy (HDSC) and autologous hematopoietic cell transplantation (AHCT). After cytoreduction with standard salvage therapy, HDSC/AHCT was administered in 4 phases at 2- to 4-week intervals. Phase 1 consisted of cyclophosphamide 7 g/m2 followed by granulocyte colony-stimulating factor (G-CSF) at 10 microg/kg per day and leukapheresis upon recovery from white blood cell nadir. The hematopoietic cell product was enriched by Percoll gradient separation and purged with a B-cell or T-cell monoclonal antibody panel and complement. Phase 2 consisted of methotrexate 8 g/m2 with leucovorin rescue and vincristine 1.4 mg/m2. Phase 3 was etoposide 2 g/m2 with G-CSF 5 microg/kg per day. In phase 4, the preparative regimen of mitoxantrone 60 mg/m2 and melphalan 180 mg/m2 was administered followed by AHCT. The NHL histologies were diffuse large cell, follicular/diffuse mixed, small noncleaved cell, T-cell-rich B-cell, lymphoblastic, and peripheral T cell. The remission status was first partial remission (PR1; n = 1) or beyond first complete remission (post-CR1; n = 19). Of the 20 patients enrolled, 11 proceeded through all 4 phases. Nine were removed from the study after the first or second phase because of progressive disease (n = 5), poor hematopoietic cell mobilization (n = 1), excessive toxicity (n = 2), and chronic active hepatitis C (n = 1). Treatment-related toxicities in the remaining 11 transplant recipients were cardiomyopathy, hemorrhagic cystitis, persistent cytopenias, acute renal failure, abnormal liver function test results, and infectious complications. There were no treatment-related deaths. Eight of the 11 transplant recipients were alive, 6 without disease, at a median follow-up of 2.7 years. The estimated median 2-year event-free survival was 55%, and overall survival was 70%. We conclude that HDSC/AHCT in refractory/recurrent NHL is associated with considerable acute and chronic toxicities. Given the toxicity profile, efficacy data were not sufficiently promising to warrant further study.

Acute Kidney Injury↗

Visualizing the kinetics of tumor-cell clearance in living animals.

Evaluation of potential antineoplastic therapies would be enhanced by noninvasive detection of tumor cells in living animals. Because light is transmitted through mammalian tissues, it was possible to use bioluminescence to monitor (both externally and quantitatively) growth and regression of labeled human cervical carcinoma (HeLa) cells engrafted into immunodeficient mice. The efficacy of both chemotherapy and immunotherapeutic treatment with ex vivo expanded human T cell-derived effector cells was evaluated. In the absence of therapy, animals showed progressive increases in signal intensity over time. Animals treated with cisplatin had marked reductions in tumor signal; 5'-fluorouracil was less effective, and cyclophosphamide was ineffective. Immunotherapy dramatically reduced signals at high effector-to-target cell ratios, and significant decreases were observed with lower ratios. This model system allowed sensitive, quantitative, real-time spatiotemporal analyses of the dynamics of neoplastic cell growth and facilitated rapid optimization of effective treatment regimens.

Animals↗

Role of natural killer cell alloreactivity in HLA-mismatched hematopoietic stem cell transplantation.

Because of the expression of inhibitory receptors (KIR) for major histocompatibility complex (MHC) class I allotypes, a person's natural killer (NK) cells will not recognize and will, therefore, kill cells from individuals lacking his/her KIR epitopes. This study investigated the role of NK cell alloreactivity in human HLA haplotype-mismatched hematopoietic stem cell transplantation and, specifically, the role of the three major NK specificities, ie, those for HLA-C group 1, HLA-C group 2, and HLA-Bw4 alleles. In 20 of 60 donor-recipient pairs, KIR epitope incompatibility and functional analyses of donor NK cell clones predicted donor NK cells could cause graft-versus-host (GVH)/graft-versus-leukemia (GVL) reactions. NK cell clones of donor origin were obtained from transplanted recipients and tested for lysis of recipient's cryopreserved pretransplant lymphocytes. Despite the absence of GVH disease, we detected high frequencies of NK clones which killed recipient's target cells. Lysis followed the rules of NK cell alloreactivity, being blocked only by the MHC class I KIR epitope which was missing in the recipient. The alloreactive NK clones also killed the allogeneic leukemia. Transplants from these KIR epitope incompatible donors had higher engraftment rates. Therefore, a GVL effector and engraftment facilitating mechanism, which is independent of T-cell-mediated GVH reactions, may be operational in HLA mismatched hematopoietic cell transplants.

Adolescent↗

Cyclosporine, methotrexate, and prednisone compared with cyclosporine and prednisone for prevention of acute graft-vs.-host disease: effect on chronic graft-vs.-host disease and long-term survival.

Graft-vs.-host disease (GVHD) is a major predictor of outcome following allogeneic bone marrow transplantation (BMT). For patients alive at day 100 after BMT, the presence or absence of chronic GVHD is one of the most important determinants of survival and quality of life. We wished to determine the effects on chronic GVHD of two regimens used for the prophylaxis of acute GVHD: cyclosporine, methotrexate, and prednisone (CSA/MTX/PSE) and cyclosporine and prednisone (CSA/PSE). One hundred forty-nine evaluable patients were entered into the acute GVHD study. As of 31 March 1997, 63 months after the last patient underwent BMT, the median survival time was 4.5 years (range 0.09-9.9). The incidence of chronic GVHD was independent of the prophylactic regimen (55 vs. 54%), and extensive chronic GVHD occurred in 25 and 24% of patients receiving CSA/MTX/PSE and CSA/PSE, respectively. Of note, the median Karnofsky performance status of both groups was 100% (range 70-100%), reflecting the low incidence of extensive chronic GVHD. Survival rates free of chronic GVHD were 52 vs. 42% (p = 0.29) for patients receiving CSA/MTX/PSE vs. CSA/PSE. The incidence of relapse was also similar in both groups of patients. These data suggest that the combinations of CSA/MTX/PSE and CSA/PSE result in comparable chronic GVHD-free survival without an increase in leukemic relapse.

Acute Disease↗

Impact of admission body weight and chemotherapy dose adjustment on the outcome of autologous bone marrow transplantation.

We performed a retrospective analysis of 473 consecutive adult patients undergoing autologous bone marrow transplantation for hematologic malignancies between 1988 and 1995. The analysis examined whether significant deviation from ideal body mass index is associated with a decrease in event-free survival (EFS), an increase in nonrelapse mortality (NRM) including late toxicities and second malignancies, or relapse. Chemotherapy dosing in underweight and overweight patients is administered based on the relationship of admission body weight (ABW) to ideal body weight (IBW). Doses were adjusted for obesity; however, the adjustment did not obviate increased risk for NRM. Patients were categorized into five groups according to the relationship of ABW to age-adjusted body mass index (aBMI) as a percent of actual BMI, as follows: group I, 70-79%; group II, 80-99%; group III, 100-119%; group IV, 120-139%; and group V, 140-199% aBMI. When body weight was expressed as percent BMI adjusted for age, there was a significantly increased risk for NRM in groups I and IV (p = 0.03 and 0.02, respectively). A trend toward greater NRM in group V (p = 0.10) was also noted. Multivariate analysis confirmed that the risk of NRM for extremely underweight and overweight patients is almost three times that of patients close to ideal body weight. Age-adjusted BMI was an independent predictive factor for NRM but not associated with increased relapse. We determined that dose adjustment could be safely used without significant increase of relapse. In patients with significant deviation of BMI from aBMI, dose adjustment and possible weight normalization should be considered.

Adolescent↗

Long-term follow-up of 23 patients with Philadelphia chromosome-positive acute lymphoblastic leukemia treated with allogeneic bone marrow transplant in first complete remission.

Between 1984 and 1997, 23 consecutive patients with Philadelphia chromosome-positive acute lymphoblastic leukemia in first complete remission were treated with allogeneic bone marrow transplants from HLA-matched siblings. All patients but one were conditioned with fractionated total body irradiation (1320 cGy) and high-dose etoposide (60 mg/kg). One patient received high-dose cyclophosphamide instead of etoposide, and another patient received both drugs. Nine patients died following BMT, two from relapsed leukemia, and seven from transplant-related causes. The 3-year probabilities of disease-free survival and relapse are 65% and 12%, respectively. For patients transplanted after 1992, these probabilities are 81% (48-95%, 95% confidence interval) and 11% (2-50%), respectively. The relatively low relapse rate in this group of patients compared to published reports may reflect the enhanced anti-leukemic activity of etoposide in combination with FTBI compared to other conditioning regimens. The enhancement in overall survival for patients transplanted after 1992 may reflect improvements in supportive care, in particular, the prophylaxis of serious fungal and viral infections.

Adult↗

Noninvasive assessment of tumor cell proliferation in animal models.

Revealing the mechanisms of neoplastic disease and enhancing our ability to intervene in these processes requires an increased understanding of cellular and molecular changes as they occur in intact living animal models. We have begun to address these needs by developing a method of labeling tumor cells through constitutive expression of an optical reporter gene, and noninvasively monitoring cellular proliferation in vivo using a sensitive photon detection system. A stable line of HeLa cells that expressed a modified firefly luciferase gene was generated, and proliferation of these cells in irradiated severe combined immunodeficiency (SCID) mice was monitored. Tumor cells were introduced into animals via subcutaneous, intraperitoneal and intravenous inoculation and whole body images, that revealed tumor location and growth kinetics, were obtained. The number of photons that were emitted from the labeled tumor cells and transmitted through murine tissues was sufficient to detect 1x10(3) cells in the peritoneal cavity, 1x10(4) cells at subcutaneous sites and 1x10(6) circulating cells immediately following injection. The kinetics of cell proliferation, as measured by photon emission, was exponential in the peritoneal cavity and at subcutaneous sites. Intravenous inoculation resulted in detectable colonies of tumor cells in animals receiving more than 1x10(6) cells. Our demonstrated ability to detect small numbers of tumor cells in living animals noninvasively suggests that therapies designed to treat minimal disease states, as occur early in the disease course and after elimination of the tumor mass, may be monitored using this approach. Moreover, it may be possible to monitor micrometastases and evaluate the molecular steps in the metastatic process. Spatiotemporal analyses of neoplasia will improve the predictability of animal models of human disease as study groups can be followed over time, and this method will accelerate development of novel therapeutic strategies.

Animals↗

A feasibility study of multiple cycle therapy with melphalan, thiotepa, and paclitaxel followed by mitoxantrone, thiotepa, and paclitaxel with autologous hematopoietic cell support for metastatic breast cancer.

Dose-intensive chemotherapy appears to be important in the treatment of patients with recurrent solid tumors. Expanding upon our prior experience, we report the results of our most recent approach to administering dose-intensive therapy using four cycles of moderately high-dose chemotherapy with hematopoietic cell support for patients with metastatic breast cancer. This outpatient therapy includes high-dose melphalan, thiotepa, and paclitaxel for two cycles followed by mitoxantrone, thiotepa, and paclitaxel for two cycles, with each cycle supported with autologous peripheral blood progenitor cells (PBPCs). Between December 1994 and June 1996, 16 patients with recurrent or refractory breast cancer were enrolled in this prospective study. They had received a median of two previous chemotherapy regimens, with a median of nine prior cycles of chemotherapy. For mobilization of autologous PBPCs, patients received cyclophosphamide, 4 g/m2, followed by granulocyte colony-stimulating factor (G-CSF). PBPCs were collected by apheresis. Each day's collection was divided into four equal fractions, and each fraction was infused after each cycle of combination therapy. Cycles 1 and 2 consisted of melphalan, 80 mg/m2, thiotepa, 300 mg/m2, and paclitaxel, 200 mg/m2. Cycles 3 and 4 were comprised of mitoxantrone, 30 mg/m2, and thiotepa and paclitaxel at the same doses as in the first two cycles. The cyclophosphamide infusion was administered in the hospital, whereas all subsequent infusions of chemotherapy and PBPCs were performed on an outpatient basis. The first seven patients were randomized to receive alternate cycle G-CSF or placebo on day +1 of each cycle. Including the initial pulse of cyclophosphamide, 67 (84%) of a planned 80 total courses of chemotherapy were delivered. Of the planned 64 cycles of high-dose combination chemotherapy, 52 cycles (81%) were delivered. Treatment was discontinued for progressive disease (one patient) or morbidity (five patients). Twelve of 16 patients completed at least three cycles of therapy. Nine patients completed all four cycles. One death resulted from fungal sepsis. In 20 cycles delivered to the first seven patients, day +1 G-CSF versus placebo was administered, with a median WBC recovery of 10 versus 13 days, respectively (P = 0.048 in cycle 1). The median duration of response was almost 9 months, and the median survival was 18 months after therapy. With a median follow-up of 1.5 years and longest follow-up of 4.2 years, two patients continue to be without evidence of disease. The 3-year event-free survival, freedom from progression, and overall survival are 19%, 20%, and 31%, respectively. This four-cycle regimen of high-dose combination therapy supported with hematopoietic progenitor cells is feasible, but it is associated with a range of posttransplant complications. The efficacy of such a treatment would have to be substantially superior to that of other currently available therapies, including single autologous transplant procedures, to justify the prolonged period of treatment, multiple episodes of pancytopenia, and associated toxicities, including infectious risks. G-CSF administration after each PBPC infusion appears to accelerate time to neutrophil recovery but does not affect red cell or platelet engraftment.

Adult↗

Expansion of Philadelphia chromosome-negative CD3(+)CD56(+) cytotoxic cells from chronic myeloid leukemia patients: in vitro and in vivo efficacy in severe combined immunodeficiency disease mice.

We have developed culture conditions for the efficient expansion of cytotoxic effector cells from peripheral blood mononuclear cells (PBMNCs) by the timed addition of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and the monoclonal antibody (MoAb) OKT3. These cells, termed cytokine-induced killer (CIK) cells, are composed primarily of T cells, and the population of cells with the greatest cytotoxic activity is an otherwise rare population of CD3(+)CD56(+) cells that expand dramatically under these culture conditions. CIK cells were expanded from PBMNCs from 13 patients with chronic myeloid leukemia (CML). These cultures contained a variable number of T cells at the start of the culture (median 44%, range 1% to 64%), yet after 21 to 28 days of culture, virtually all of the cells were CD3(+) T cells (median 97%, range 90% to 99%). The CD3(+)CD56(+) subset of cells expanded significantly (median 25-fold, range 2.2- to 525-fold). CIK cells from all patients showed cytotoxicity against the tumor cell lines OCI-LY8 and K562. In four patients the expanded CIK cells suppressed colony growth of autologous CML blast cells and myeloid progenitor cells. Allogeneic CIK cells from normal donors also suppressed CML colony growth but did not inhibit growth of normal hematopoietic colonies. Twelve of the 13 cultures were exclusively composed of Philadelphia (Ph)-negative cells and one culture had 1 out of 20 Ph-positive metaphases after 4 weeks in culture. Intracellular cytokine production was assayed by fluorescence-activated cell sorter (FACS), and the expanded T-cell cultures produced IL-2, IFN-gamma, and tumor necrosis factor-alpha (TNF-alpha), but not IL-4. Both the CD4(+) and CD8(+) subsets secreted this cytokine profile. To test the in vivo activity of the expanded CIK cells, CML was engrafted into severe combined immunodeficiency disease (SCID) mice using matrigel. After 4 weeks, 4 x 10(7) autologous CIK cells were injected intravenously by tail vein injection into groups of mice, and the animals were sacrificed after a total of 18 weeks. Bcr-abl was detected in the bone marrow or spleen of 5 out of 6 control mice and only 2 out of 13 mice who received the autologous CIK cells (P = .02). In an additional series of animals, the mice did not engraft with CML but instead developed large human Epstein-Barr virus-associated lymphomas by 12 weeks. The mice who received autologous CIK cells at 4 weeks had either no tumor (5) or small tumors (5), whereas all 10 mice that received CIK cells at week 8 developed lymphomas; however, these were not as large as in the 10 control mice who did not receive CIK cells (P = . 03). This study shows that CIK cells, which are Ph chromosome-negative, can be expanded from patients with CML and have potent in vitro and in vivo efficacy against autologous tumor cells.

Animals↗

A multicenter study of platelet recovery and utilization in patients after myeloablative therapy and hematopoietic stem cell transplantation.

An observational study was conducted at 18 transplant centers in the United States and Canada to characterize the platelet recovery of patients receiving myeloablative therapy and stem cell transplantation and to determine the clinical variables influencing recovery, determine platelet utilization and cost, and incidence of hemorrhagic events. The study included 789 evaluable patients transplanted in 1995. Clinical, laboratory, and outcome data were obtained from the medical records. Variables associated with accelerated recovery in multivariate models included (1) higher CD34 count; (2) higher platelet count at the start of myeloablative therapy; (3) graft from an HLA-identical sibling donor; and (4) prior stem cell transplant. Variables associated with delayed recovery were (1) prior radiation therapy; (2) posttransplant fever; (3) hepatic veno-occlusive disease; and (4) use of posttransplant growth factors. Disease type also influenced recovery. Recipients of peripheral blood stem cells (PBSC) had faster recovery and fewer platelet transfusion days than recipients of bone marrow (BM). The estimated average 60-day platelet transfusion cost per patient was $4,000 for autologous PBSC and $11,000 for allogeneic BM transplants. It was found that 11% of all patients had a significant hemorrhagic event during the first 60 days posttransplant, contributing to death in 2% of patients. In conclusion, clinical variables influencing platelet recovery should be considered in the design and interpretation of clinical strategies to accelerate recovery. Enhancing platelet recovery is not likely to have a significant impact on 60-day mortality but could significantly decrease health care costs and potentially improve patient quality of life.

Antigens, CD34↗

Engraftment of chronic myeloid leukemia in SCID mice.

Chronic myeloid leukemia (CML) is a clonal disorder of primitive hematopoietic stem cells characterized by a reciprocal translocation between chromosomes 9 and 22. Animal models of CML would be useful to study the biology and potential therapies in this disease. Mice with severe combined immunodeficiency (SCID) which will accept human xenografts have been useful in the study of a variety of human malignancies. CML has been difficult to establish in SCID mice possibly due to the lack of a functioning human stroma and relevant cytokines. To facilitate engraftment we injected cells in matrigel which is a soluble extract of basement membranes; is liquid below 22 degrees C and gels at 37 degrees C. CD34+ myeloid blast crisis cells (2 x 10(6)) were mixed in matrigel and injected subcutaneously into 10 SCID mice. All mice developed large tumours which spread to the mouse BM and spleen. However the percentage of human cells in the mouse BM and spleen was variable and ranged from 1 to 50 per cent. In contrast chronic phase (CP) CML cells mixed in matrigel did not form subcutaneous tumours and spread to the BM and spleen was detectable by PCR and not macroscopically. Groups of mice were injected with matrigel containing 1-20 x 10(7) MNC (2-20 x 10(5) CD34+ cells) from five patients with CP CMP. Bcr-abl sequences were detected by RT-PCR in the peripheral blood (PB) of 38/84 (45 per cent) mice at 3-10 weeks following injection of the CML cells but rarely at later time points. In addition, 33/75 (44 per cent) of mice sacrificed between 7 and 35 weeks following injection of CML cells were bcr/abl positive in the bone marrow and 17/70 (24 per cent) were positive in the spleen. Bcr-abl positive human CFU-GM colonies were also cultured from the murine bone marrow of several mice indicating that hematopoietic progenitor cells were able to migrate from the matrigel and engraft in murine hematopoietic organs. Engraftment of CP-CML was more successful in mice given higher numbers of CD34+ cells. Histological examination revealed that myeloid cells grow locally in the matrigel for several weeks, during which time the matrigel is infiltrated by blood vessels which may allow for the migration of CML progenitors to the murine bone marrow. This model system may be useful for studying the role of immunotherapy after allogeneic and autologous bone marrow transplantation.

Adult↗

CD34 enumeration.

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Antigens, CD34↗

Minimal residual disease.

A major limitation in the treatment of malignant disorders is the accurate and sensitive detection of minimal residual disease. It is clear that routine radiographic and pathologic studies are extremely important, however, lacking in sensitivity. Clearly, the goal of minimal residual disease detection is to make individual treatment decisions such that those patients who require more aggressive approaches are treated promptly and to avoid toxic and expensive treatments for those patients who do not require them. To reach this goal two milestones are required. The first is to develop and standardize sensitive and specific tools to detect minimal residual disease. The second is to determine whether these tools in fact predict clinical outcome. This review is divided into two parts. In the first section, recent advances in the detection of minimal residual disease will be discussed. This will be followed by studies reported in the past year that have attempted to determine whether those assays are reliable and predict clinically relevant endpoints.

Clinical Trials as Topic↗

Granulocyte colony-stimulating factor-induced comobilization of CD4- CD8- T cells and hematopoietic progenitor cells (CD34+) in the blood of normal donors.

The feasibility of transplantation of HLA-matched hematopoietic progenitor cells from the blood of normal donors given granulocyte colony-stimulating factor (G-CSF) has been reported recently. In the current study, the changes in T-cell subsets as well as CD34+ cells were determined in one blood volume leukapheresis products of six normal individuals given G-CSF. Examination of the T-cell subsets in the leukapheresis products showed three different patterns: one in which a discrete population of CD4- CD8- alphabeta T cells was found in addition to the typical CD4+ and CD8+ T cells in the unfractionated as well as in high- and low-density cells; a second in which the discrete population of CD4- CD8- alphabeta T cells was predominant only in the low-density fractions; and a third in which a discrete population of CD4- CD8- T cells was not observed. The median yield of CD4- CD8- T cells was about fourfold to fivefold higher than the calculated number present in one blood volume (5L) from normal individuals. The ratios of CD34+ cells to CD4+ and CD8+ T cells, and of CD4- CD8- T cells to CD4+ and CD8+ T cells, were highest in the low-density fractions. These fractions suppressed the mixed leukocyte, and may ameliorate graft-versus-host disease as compared with unfractionated cells.

Adult↗