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Background: The clinical relevance of tumor cell purging of hematopoietic progenitor cell grafts has yet to be conclusively determined. Therefore, in addition to the demonstration that a method for graft purification is capable of removing an adequate number of tumor cells, it is critical that the procedure has as benign an impact upon the hematopoietic repopulating potential of the graft as possible. We evaluated tumor cell depletion, recovery of CD34[sup +] cells and post transplant engraftment kinetics as accepted measures of the effectiveness of an immunomagnetic bead (positive and positive/negative) purging methodology. Methods: The patients received either positive selection (CD34 selection alone) or a combination of positive and negative (CD34 selection followed by breast cancer cell depletion) using the Isolex 300 (automated and semiautomated) devices. Immunocytochemistry was used to determine the degree of breast cancer cell contamination before and after the selection procedures to determine the efficacy of the procedure. CD34 enumeration was employed to evaluate the recovery and purity of the CD34-selected cellular products and engraftment indices (days to absolute neutrophil count (ANC) recovery and platelet count (Plt) recovery and transfusion requirements) were evaluated to determine the safety of the procedure. Results: A total of 130 aphereses was performed on 101 patients. Ten pairs of collections were pooled before selection to increase the likelihood of achieving CD34 dose goals after selection. In all, 100 positive selections and 20 positive/negative selections were performed. Of the 10 (10.4%) ICC-positive preselection samples, 2 products showed persistent contamination after processing. The majority of patients (85.4%) required one selection procedure to achieve an adequate CD34[sup +] selected cell dose. Median CD34[sup +] cell recovery was > 50% for positive selection procedures and > 60% for the positive/negative procedures. The dose of CD34[sup +] cells infused ranged from 0.76 × 10[sup 6] CD34[sup +] cells/kg to 27.7 × 106 CD34[sup +] cells/kg. There were no significant delays in neutrophil or platelet recovery or infections between any of the treatment groups. Discussion: CD34 selection alone or in combination with negative selection can result in a significant reduction of contaminating tumor cells in the peripheral blood progenitor cell autograft. Although there was one engraftment failure with the CD34-positive selected cells, transplantation of the selected products after high-dose chemotherapy for metastatic breast cancer did not result in a clinically significant delay in the hematopoietic reconstitutive capacity of the autografts. [ABSTRACT FROM AUTHOR]

We analyzed the safety and efficacy of Mylotarg (gemtuzumab ozogamicin, an antibody-targeted chemotherapy consisting of a humanized anti-CD33 antibody linked to calicheamicin, a potent antitumor antibiotic) in the treatment of 101 patients > or =60 years of age with acute myeloid leukemia (AML) in untreated first relapse in three open-label trials. Mylotarg is administered as a 2-h intravenous infusion at 9 mg/m(2) for two doses with 14 days between doses. The overall remission rate was 28%, with complete remission (CR) in 13% of patients and complete remission with incomplete platelet recovery (CRp) in 15%. Median survival was 5.4 months for all patients and 14.5 months and 11.8 months for patients achieving CR and CRp, respectively. CD33 antigen is present on normal hematopoietic progenitor cells; thus, an expected high incidence of grade 3 or 4 neutropenia (99%) and thrombocytopenia (99%) was observed. The incidences of grade 3 or 4 elevations of bilirubin and hepatic transaminases were 24% and 15%, respectively. There was a low incidence of grade 3 or 4 mucositis (4%) and infections (27%) and no treatment-related cardiotoxicity, cerebellar toxicity, or alopecia. Mylotarg is an effective treatment for older patients with CD33-positive AML in first relapse and has acceptable toxicity.

Allogeneic donor leukocytes can be used after nonmyeloablative conditioning to exploit their graft-versus-tumor (GVT) activity in the setting of reduced conditioning-regimen toxicity. This approach may be particularly useful for patients who relapse after autologous stem cell transplantation (SCT). However, GVT activity, toxicity, and ability to establish mixed chimerism may differ in patients who were heavily pretreated prior to SCT compared with patients treated earlier in the course of their disease. We have performed a series of studies of nonmyeloablative allogeneic transplantation and present data on the subset of 14 patients treated for relapse after autologous SCT: 4 patients received no conditioning and unstimulated donor leukocyte infusions (DLI), 10 patients received conditioning with fludarabine and cyclophosphamide followed by unstimulated or granulocyte-colony-stimulating factor (G-CSF)-stimulated allogeneic peripheral blood stem cells (PBSCs), 4 patients received no graft-versus-host disease (GVHD) prophylaxis, and 10 patients received cyclosporine GVHD prophylaxis. All but 1 patient had sustained donor chimerism at least 30 days after allogeneic cell therapy (ACT), and 8 patients had more than 80% donor chimerism after ACT. Acute GVHD developed in 11 patients (grade III-IV, n = 6). Aplasia was more frequent in the patients receiving unstimulated PBSCs, despite the development of mixed chimerism. There were 6 complete responses and 4 partial responses; response was independent of conditioning and growth-factor stimulation of the donor graft. Five patients died of treatment-related causes and 4 patients died from progressive disease. Four patients remained alive 27 to 194 weeks (median, 66 weeks) after ACT. Prior autologous SCT may define a subset of patients at particularly high risk for GVHD and other toxicity after ACT. However, these data show that ACT with either DLI or G-CSF-stimulated blood cells results in direct GVT activity in some patients with Hodgkin's disease, myeloma, and non-Hodgkin's lymphoma, even after relapse from autologous SCT. Most patients developed donor chimerism with minimal conditioning. Alternative prophylactic regimens that control GVHD while maintaining GVT are needed to improve outcomes in these heavily pretreated patients.

The human cytotoxic T-cell line TALL-104 displays antitumor effects in animals with implanted and spontaneous malignancies. A Phase I trial was conducted to determine toxicity of TALL-104 cell therapy in women with metastatic refractory breast cancer. Fifteen patients with metastatic infiltrating ductal (n = 12), lobular (n = 2), or medullary (n = 1) carcinoma received escalating doses of lethally irradiated TALL-104 cells (three patients/group received 10(6), 3 x 10(6), 10(7), 3 x 10(7), and 10(8) cells/kg) for 5 consecutive days (induction course). Patients without progressive disease received monthly maintenance 2-day infusions at the same dose level. Mild grade I/II toxicity developed in 11 patients regardless of cell dose. One grade IV toxicity consequent to hepatic tumor necrosis occurred in a patient given 10(8) cells/kg, 3 weeks after the induction course. Nine patients progressed within 1 month from induction, and five patients had stable disease for 2-6 months. One patient (at 3 x 10(7)/kg) had improvement of liver metastases and ascites, and a second patient (at 10(6)/kg) experienced a dramatic relief in bone pain. Increases in blood natural killer cell activity and levels of IFN-gamma, interleukin-10, and activation markers (soluble interleukin-2 receptor and soluble intercellular adhesion molecule-1) were often seen. Only one patient developed anti-HLA class I antibody responses against TALL-104 cells; specific CTL activity developed in three patients during induction and in four patients during the maintenance boosts. In conclusion, TALL-104 cells were well tolerated by patients with metastatic breast cancer at the doses and regimen tested. The clinical responses observed in this preliminary trial demonstrate that further investigation of TALL-104 cell therapy is warranted.

In this prospective, multicenter, phase 2 study, multiple myeloma (MM) patients with primary resistant disease or recurrent chemosensitive disease, in chemoresistant relapse, or in second or subsequent remission were treated with high-dose chemoradiotherapy followed by autologous peripheral blood stem cell (PBSC) rescue. PBSCs were collected using granulocyte-macrophage colony-stimulating factor (GM-CSF) 5 microg/kg per day subcutaneously for 3 days. Patients underwent high-dose chemoradiotherapy consisting of melphalan (140 mg/m2 x 1 day), cyclophosphamide (60 mg/kg per day x 2 days), methylprednisolone (2 g/d x 7 days), and total body radiation (150 cGy bid x 3 days) followed by peripheral blood stem cell reinfusion (> or = 1.2 x 10(9) mononucleated cells per kg) and GM-CSF support (5 microg/kg per day) and were evaluated for response, survival, and toxicity. Thirty-six patients, median age 53.4 years, completed the study. The mean pretransplantation cumulative melphalan dose was 464 +/- 72 mg. Excluding the 3 patients (8.3%) who failed to engraft, the median times to engraftment and platelet recovery were 10 days (range, 8-39 days) and 17 days (range, 7-67 days), respectively. Four patients (11.1%) died of complications related to the regimen (main causes of death, sepsis and acute respiratory distress syndrome) within the first 100 days. Twenty-two patients (61.1%) achieved complete response (CR), 8 (22.2%) partial response, and 2 (5.5%) no response. Two patients developed myelodysplastic syndrome after achieving CR. For all 36 patients, the probability of overall survival at 5 years was 27.3%. Median survival was 31 months (range, 0.3-81 months) in all patients and 42 months (range, 3.4-81 months) in those with CR. The probabilities of overall and disease-free survival at 5 years for the 22 patients who achieved CR were 43.6% and 15.7%, respectively. This high-dose chemotherapy regimen coupled with PBSC rescue is associated with a high CR rate and is capable of inducing long-term survival in a subset of heavily pretreated patients with primary resistant or recurrent MM.

Background: High-dose chemotherapy with autologous stem-cell transplantation is used increasingly in the treatment of poor-prognosis primary breast cancer. Because these patients may be cured with standard multimodality therapy, it is important to address both the efficacy of transplantation, and its effect on the delivery of standard treatments including local radiation therapy., Patients and Methods: Patients with high risk primary breast cancer were treated with high-dose cyclophosphamide and thiotepa and stem-cell transplant following surgery and conventional-dose adjuvant chemotherapy. Outcome, including sites of failure and delivery of local radiation therapy, was assessed for 103 patients., Results: Overall and disease-free survival rates at 18 months were 83% (+/- 4%) and 77% (+/- 4%) respectively. Twenty patients (19.4%) received radiation therapy prior to transplant. Of the remaining 83, 77 received radiation therapy after transplant. Overall, 5 (19.2%) of 26 first sites of recurrence were local alone. For patients receiving radiation prior to transplant, 3 of 7 (43%, 95% CI: 6%-80%) sites of first recurrence were local, while 2 of 19 (10.5%, 95% CI: 0%-24.5%) sites of first recurrence were local alone in patients receiving post-transplant radiation or no radiation., Conclusion: Transplantation does not appear to significantly compromise the delivery or outcome of local radiation therapy for primary breast cancer.