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Background: Between 20% and 30% of patients with advanced germ cell tumors (GCTs) fail to have durable complete response to conventional cisplatin-based induction chemotherapy. However, third-line therapy with high-dose carboplatin and etoposide plus autologous bone marrow transplantation (AuBMT) has induced durable complete response in 10%-20% of patients with cisplatin-resistant GCT.Purpose: We conducted a phase II trial of first-line therapy that included high-dose carboplatin and etoposide plus AuBMT in untreated men with advanced GCTs and unfavorable prognosis (i.e., "poor-risk" patients).Methods: Twenty-eight patients were treated with a conventional-dose, cisplatin-containing regimen (VAB-6 [cisplatin, vinblastine, bleomycin, cyclophosphamide, dactinomycin]) with or without high-dose carboplatin (1500 mg/m2) and etoposide (1200 mg/m2) plus AuBMT. Twenty-two of these patients were selected for treatment with two cycles of high-dose carboplatin and etoposide plus AuBMT when reduced clearance of serum tumor markers (alpha-fetoprotein [AFP] or human chorionic gonadotropin [HCG]), as evidenced by prolonged half-life (> 7 days for AFP and > 3 days for HCG), was observed after two cycles of conventional treatment.Results: Fifteen (56%) of 27 patients considered assessable for response achieved a complete response (12 treated with high-dose chemotherapy plus AuBMT). Sixteen (57%) are alive; 13 (46%) are free of disease at a median follow-up of 31.2 months. For 36 cycles of high-dose chemotherapy, the median duration from bone marrow infusion until a granulocyte count of 0.5/mm3 and a platelet count of 50,000/mm3 was 16 days (range, 7-41 days and 8-30 days, respectively). Analysis showed a trend toward improved survival (P = .07) in patients treated with high-dose chemotherapy in this study, compared with 68 poor-risk patients with GCT treated with conventional-dose therapy alone in two earlier studies. Toxicity was not cumulative, and recovery of blood counts after AuBMT was generally rapid.Conclusions: Inclusion of high-dose carboplatin-containing chemotherapy in treatment of poor-risk GCT patients is feasible when serum tumor marker half-life is used to predict resistance to standard cisplatin-based therapy. High-dose therapy in this setting was well tolerated.Implications: Early use of a dose-intensive regimen may increase survival compared with conventional-dose therapy alone. Further studies with standard induction therapy and intensive high-dose therapy using hematopoietic growth factor support are warranted, followed by a randomized trial comparing this strategy with standard therapy. [ABSTRACT FROM AUTHOR]

With growing epidemiologic and molecular evidence linking the pathogenesis of diabetes mellitus and oncogenesis, the role of anti-diabetic drugs as antineoplastic agents becomes a subject of intense investigation. Several trials are underway assessing the effect of adding metformin to the existing chemotherapy regimen in the treatment of cancers. This review has a focus on other commonly used drugs classified into two broad groups, incretins and thiazolidinediones. The aim of this review is to discuss the common genetic polymorphisms implicated in the pathogenesis of type 2 diabetes mellitus (type 2 DM) and how they are linked to molecular pathways involved in carcinogenesis., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Understanding of molecular regulatory pathways presents a novel therapeutic approach for the treatment of head and neck cancer. These specific check points are becoming the targeted therapeutic approach. In this review, we highlight certain major signaling mechanisms, which are involved in the pathophysiology of head and neck cancer. Also, we discuss the current ongoing trials based on the in vitro success of targeted therapies.

Our study examines factors influencing demand for contraception for spacing as well as for limiting births in India. Data on socio-economic, demographic and program factors affecting demand for contraception in India are from the National Family Health Survey, 1998--99. The recent document from the National Rural Health Mission has completely ignored the use of contraception in controlling fertility in India. Empirical results of our study suggest giving priority to and focusing attention on supply-side factors such as a regular and sustained supply of quality contraceptive methods to improve accessibility and affordability. Further, strengthening the information, education and communication (IEC) component of the reproductive and child health (RCH) package would allay misapprehensions about the side effects and health risks of contraception. Focusing attention on demand-side factors such as women's empowerment through education, gainful employment and exposure to mass-media would help reduce the unmet demand for family planning. The resulting reduction in fertility would hasten the process of demographic transition and population stabilization in India.

Purpose: To evaluate the occurrence of pregnancy after bone marrow transplantation (BMT)., Design: Medline literature review of reported pregnancies in the BMT population published in the English language., Results: Multiple case reports and a few series studies showed more than 250 offspring from BMT recipients., Conclusion: BMT patients receive high-dose chemotherapy and often radiation, as well. These agents are associated with gonadal dysfunction and the fertility of patients after BMT is of concern because BMT patients are often young people who wish to resume a normal quality of life, which for many patients involves the desire to have children. Our experience with the successful pregnancy of one of our BMT patients led to the investigation of reported cases that showed numerous other births. The issue of counseling BMT patients about fertility, pregnancy complications, and potential birth defects is becoming increasingly complex and warrants further investigation.

Purpose: To improve response and survival rates in patients with high-risk rhabdomyosarcoma (RMS), extraosseous Ewing's sarcoma, and undifferentiated sarcoma, we used a short course of induction with multi-agent chemotherapy, hyperfractionated radiotherapy, and surgery when possible. Consolidation was with intensive chemotherapy and autologous bone marrow transplantation (ABMT)., Patients and Methods: Twenty-six patients (21 with RMS, three with undifferentiated sarcoma, and two with extraosseous Ewing's sarcoma) were entered onto the protocol between June 1990 and March 1994. Induction consisted of ifosfamide, etoposide, doxorubicin, dactinomycin, cyclophosphomide, and vincristine, and a split course of hyperfractionated radiotherapy. Patients who attained a complete response (CR) or good partial response (GPR) received consolidation with high-dose melphalan and etoposide followed by ABMT., Results: Of 26 previously untreated patients 19 (73%) achieved a CR (n=13) or GPR (n=6) at the completion of induction and underwent ABMT. Two-year overall survival (OS) was 56% (95% confidence interval [CI], 36% to 76%) and progression-free survival (PFS) was 53% for the whole group (95% CI, 33% to 73%)., Conclusion: Consolidation of response by myeloablative chemotherapy was well tolerated. Split-course hyperfractionated radiotherapy did not increase the rate of local control. The results of this short-course therapy were comparable to previous therapies of 1 to 2 years' duration. Induction and consolidation chemotherapy, as well as radiation dose, could be further intensified, since no death due to toxicity occurred among these patients.

Mutations of the p53 tumor suppressor gene have been used as molecular genetic markers of disease and serve as a prognostic indicator in various malignancies including non-Hodgkin's lymphoma (NHL). Alterations in the p53 gene were investigated in a bone marrow sample from a NHL patient admitted for autologous bone marrow transplantation. Diffuse mixed small and large cell NHL, was initially diagnosed which eventually progressed to large cell lymphoma at relapse following poly-chemotherapy. A sequential technique of polymerase chain reaction-mediated single-strand conformational polymorphism (PCR-SSCP) of the p53 gene revealed a shift in one band of exon 6 in the bone marrow, collected at the time of initial diagnosis. No mutations were detected in exons 5, 7, 8 and 9. Direct sequencing of exon 6 detected a single base change from G to C resulting in an amino acid substitution from glycine to histidine. Results of this study and data reviewed from other publications suggest that the missense p53 mutation seen in this patient at the time of diagnosis may perhaps have been used to predict the eventual outcome of the disease. This could, therefore, serve as an important genetic disease marker particularly in bone marrow or peripheral blood samples initially collected and cryopreserved for future possible autologous transplantation.

Successful autologous bone marrow transplantation (ABMT) and peripheral blood stem cell transplantation depend on safe hematopoietic stem cell (HSC) cryopreservation and storage. Several successful methods for cryopreservation and storage have been established and are commonly used all over the world. However, little is known about the effects of long-term cryopreservation on the capacity to sustain a complete immunohematopoietic engraftment. Several authors have investigated stem cell viability after cryopreservation and storage for more than 5 years and reported preclinical good viabilities in terms of dye-exclusion or colony-forming capability in vitro. Only two studies using BM cryopreserved for more than 5 years for transplantation are reported, but they did not provide proof of trilineage engraftment. In February 1997 at our institution, a patient with relapsed non-Hodgkin's lymphoma underwent ABMT with BM harvested in February 1990. He achieved a granulocyte count > 500 x 10(6)/L on day 21 and a self-supporting platelet count > 20 x 10(9)/L on day 30. After day 29, his hemoglobin level was satisfactory without need of transfusion support. This successful trilineage engraftment with cryopreserved BM that had been stored for 7 years suggests that HSC are able to maintain their capability to reconstitute hematopoiesis for a long time.

In the chronic wound, the normal cascade of inflammation, granulation and reconstruction phases of healing is interrupted. Cytokines are now known to orchestrate different biochemical mediators resulting in the restoration of the healing phases. Growth factors may play a significant role in stimulating wound repair by stimulating growth and proliferation. Since growth factors stimulate a variety of functions depending on cell type and wound stage and since wound-healing defects may occur at any phase of healing, a mixed combination of growth factors would be predicted to be more effective than a single factor. Factors that may modulate the action of growth factors include electrical stimulation, weight bearing, debriding and ischemia.

Patients with non-myeloid hematologic malignancies (including Hodgkin's and non-Hodgkin's lymphomas, myeloma and acute lymphoid leukemia) or solid tumors underwent cytoreductive conditioning regimens followed by either autologous bone marrow transplantation (ABMT) (n = 343) or transplantation of peripheral blood stem cells (PBSC) with (n = 44) or without bone marrow (BM) (n = 16). In a randomized double-blind phase III multi-center trial, patients received either granulocyte-macrophage colony-stimulating factor (GM-CSF, 10 micrograms/kg/day) or placebo by daily i.v. infusion beginning 24 h after bone marrow infusion and continuing until the absolute neutrophil count (ANC) had recovered to > or = 1000/mm3, or for a maximum of 30 days. Median time to neutrophil recovery was significantly shorter in the GM-CSF group (18 vs 27 days, P < 0.001), and more GM-CSF patients had neutrophil recovery by day 30 (70 vs 48%). Median duration of hospitalization was significantly shorter in the GM-CSF group (29 vs 32 days, P = 0.02). GM-CSF significantly reduced the median time to neutrophil recovery in patients receiving bone marrow only (19 vs 27 days, P < 0.001) or PBSC with or without bone marrow (14 vs 21 days, P < 0.001). The overall incidence of adverse events was comparable in the two groups, although more patients in the GM-CSF group discontinued treatment due to adverse events (17 vs 9%, P < 0.001). No difference was noted in infection incidence or time to platelet independence. GM-CSF had no negative impact on time to relapse or long-term survival. These data indicate the positive influence of GM-CSF on neutrophil recovery and hospital stay in patients receiving ABMT for a variety of clinical indications.

Study Objective: To assess the experience with autologous bone marrow harvesting in outpatients., Design: Retrospective analysis of outpatients who underwent autologous bone marrow harvesting from 1990 to 1992., Setting: University-affiliated surgical day hospital., Subjects: 235 outpatients who underwent 264 autologous bone marrow harvests. Patients are candidates for autologous bone marrow harvesting on an outpatient basis if they are Karnofsky performance status of 80-100 and ASA status I, II or III., Measurements and Main Results: The incidence of perioperative complications and hospital admission from the Surgical Day Hospital, the duration of the harvesting procedure and postanesthesia care unit (PACU) stay, details of the postoperative pain management, and costs and charges of the outpatient procedure compared with the same procedure performed on inpatients were assessed. Mean age was 37.7 years +/- 10.5 SD; + 7.7% patients were male and 52.3% were female. The disease process included non-Hodgkin's lymph/ma (30.3%), leukemia (24.3%), metastatic breast cancer (18.4%), Hodgkin's disease (17.3%), testicular carcinoma (6.5%) and other (1.6%). The patients were ASA status II (54.5%) or ASA III (45.5%) and received general endotracheal anesthesia. Each patient had 10.7 ml/kg +/- 2.8 SD of marrow harvested over a period of 110.7 minutes + 30.4 SD and total recovery room time of 233.7 minutes +/- 85.5 SD. Of 251 harvest, only three (1.1%) required hospital admission. PACU complaints included transient hypotension and dizziness (5.3%), nausea (3.8%), vomiting (3.4%), and (1.9%) temperature elevation. 83.7% of patients were reached at home the following day and 4.1% complained of nausea and/or vomiting at home. 6.8% of patients experienced temperature elevation at home. Only 27.1% of patients took the acetaminophen with codeine that was prescribed. The reminder required no opioid at home. Outpatient charge/ inpatient charge was 51.1%, and outpatient cost/inpatient was 74.4%., Conclusion: Autologous bone marrow harvesting is an acceptable ambulatory surgical procedure that results in a very law postanesthesia complication rate. Postoperative pain is easily controlled. The outpatient setting offers cost and time advantages to the patient.

With the increasing concern over the high cost of health care, policy makers have incorporated economic analyses into phase III clinical trials as the randomized clinical trials can provide important information on the efficacy and potential cost-effectiveness of new pharmaceutical agents. Economic analyses of single-hospital experience during phase III trials of granulocyte-macrophage colony-stimulating factor (GM-CSF) as adjunct therapy for high dose chemotherapy with autologous stem cell support found significant shortening of neutropenia with GM-CSF at each hospital, but shortened hospitalization (and lower costs) at only two of three hospitals. In this study, we added data from three additional hospitals and found that the 103 patients who received GM-CSF had, on average, 5.7 days shorter durations of severe neutropenia than the 95 patients who received placebo (p < 0.0001) and 3.4 days shorter in hospitalization (p = 0.06). However, the duration of hospitalization, the primary determinant of health care costs, was shorter for GM-CSF patients in only four of the six centers and the duration of hospitalization of placebo patients was shorter at the other two centers. Careful analyses must be carried out when phase III clinical trial results are used to derive estimates of cost-effectiveness of new pharmaceutical agents. The interpretation of economic analyses of phase III clinical trials raises issues related to the perspective of the investigators, study design, collection of data on resource utilization, learning curve effects and generalizability of the results to other settings.

Although the role of hematopoietic stem-cell transplantation (HSCT) in cancer treatment is rapidly expanding, decreasing the side effects of stem-cell infusion is a major challenge. Cancer cells present in the stem-cell collection can cause relapse after autologous transplantation. In allogeneic transplantation. T lymphocytes contribute to graft-versus-host disease. Various methods of purging have been used to remove these unwanted cells, and there is some evidence that such manipulations are clinically useful. Nevertheless, the inability to detect minimal disease makes it difficult to determine whether relapse is caused by incomplete disease eradication in the patient or by the infused cells. This makes it hard to justify the clinical benefit of ex vivo purging. Researchers can focus on this issue by designing studies with minimal variation in other factors that affect the success of stem-cell transplantation.

Although clinical trials are being used to evaluate economic outcomes of new agents, there are methodological problems. Decisions based on these analyses may lead to inefficient use of medical resources. Randomized clinical trials provide important information on the efficacy of new pharmaceutical agents for cancer patients. Policy makers are likely to require both economic and clinical data in order to approve pharmaceuticals for widespread use. Clinical trials provide an opportunity to evaluate economic outcomes for new agents. However, the interpretation of economic analyses of clinical trials raises issues related to perspective of the investigators, study design, collection of data on resource utilization, and generalizability of data to other settings. In this paper, we review these issues and illustrate problems associated with analyses of economic data from a recent phase III trial of hematopoietic growth factors. Clinical results were similar in both Paris and New York in this phase III trial. However, economic results differed markedly between the hospital in Paris and the hospital in New York. While significant savings in terms of fewer days in the hospital and fewer laboratory tests and radiographs for the granulocyte-macrophage colony-stimulating factor (GM-CSF) patients were noted at the New York hospital, resource savings were not identified at the hospital in France. Caution must be used when reimbursement policies are based on economic analyses of clinical trials. Policy decisions must be based on studies that are carefully conducted, analyzed, and interpreted from both a clinical and an economic perspective.

Laboratory studies have suggested that hematopoietic growth factors (GF), combined with cytosine-arabinoside (Ara-C) can enhance cytotoxic effects of this agent against acute myeloid leukemia (AML) cells. While clinical trials based on this growth factor/chemotherapy combination (GF/CT) are progressing with discordant results, further information regarding the underlying mechanisms have been reported supporting this rationale and requiring additional investigation. To assess the role of cytokinetic changes in the GF/CT strategy and to evaluate if chemotherapeutic agents regimens other than Ara-C, when combined with GF, can enhance their cytotoxic effects, we have primed AML blasts with two cytokine combinations and then exposed these cells to the S-phase specific agent Ara-C as well as to the phase non-specific drug daunorubicin (DNR) and to the alkylating agent 4-hydroperoxycyclophosphamide (4-HC). The two cytokine combinations used for priming AML blasts were: (i) interleukin-3 (IL-3) + granulocyte-macrophage colony-stimulating factor (GM-CSF) + granulocyte colony-stimulating factor (G-CSF); and (ii) GM + G-CSF. Cytokinetic analysis in ten AML samples and clonogenic growth of leukemic colonies (CFU-L) in methylcellulose were used to detect proliferative and cytotoxic effects on AML samples. We report that in AML clonogenic cell growth can be stimulated by cytokines in 50% of the samples (4/8), and that Ara-C sensitization clearly occurs in two out of these four samples. Among the different cytokine combinations tested, the one containing IL-3 was the most effective through a cytokinetic mechanism consistent with recruitment (averaged G0 decrease p = 0.04; S-phase increase p = 0.005). Furthermore we observed increased cytotoxicity also to the phase non-specific drugs DNR and 4-HC, which may be mediated by other mechanisms recently described. We conclude that GF/CT combinations may also be beneficial in regimens containing drugs other than Ara-C, used for AML treatment, including bone marrow transplantation conditioning regimens.

We describe the excretion of Ascaris lumbicoides, an intestinal roundworm, in the emesis of an asymptomatic patient undergoing total body irradiation. This suggests that Ascaris is sensitive to irradiation.

Human CD34+ hematopoietic cells were purified using the avidin-biotin immunoabsorption technique. The selected population showed 78.6 +/- 3% CD34+ cells and the overall recovery of CD34+ cells, CFU-GM and BFU-E from the starting population was 34 +/- 5%, 71 +/- 4% and 67 +/- 2%, respectively. Hematopoietic progenitor cell purification also resulted in 3 log of normal T cell depletion from the bone marrow (BM) by immunofluorescence analysis. Moreover, when unseparated BM cells were mixed with the CD34- lymphoma cell lines D430B and Raji, the removal of greater than 3 log of tumor cells from the enriched CD34+ cell fraction was demonstrated. To increase the neoplastic cell purging, several immunotoxins (IT) containing the ribosome-inactivating protein (RIP) saporin and directed toward the lymphoid-associated antigens CD30 and CD2 were prepared. Our experiments showed only a minimal toxicity of the immunoconjugates on colony-forming cells (CFC) derived from purified CD34+ cells. Conversely, all the ITs were very effective in inhibiting protein synthesis and growth of normal and neoplastic lymphoid cells. Further experiments demonstrated that the sequential combination of CD34+ cells purification and IT treatment resulted in 5 or more log of tumor cell purging with no additional loss of BM progenitor cells.

Emergence of drug resistance with conventional cytotoxic therapy is a major challenge towards the curability of many cancers, especially in patients undergoing autologous BMT with ex-vivo purged hematopoietic support. We have explored the potential role of photoradiation therapy in purging hematopoietic stem cells of various hematological malignancies. Benzoporphyrin derivative, monoacid ring A (BPD-MA), dihematoporphyrin ether (DHE), and MC-540 were evaluated for the "ex-vivo" purging of residual tumor cells from autologous bone marrow (BM) grafts. BPD-MA and DHE photosensitizing activity was tested against two human large cell lymphoma cell lines and colony forming-unit leukemia (CFU-L) derived from patients with acute myelogenous leukemia (AML). In mixing experiments four log elimination of tumor cell lines was observed after 1 hr of incubation with BPD-MA or DHE followed by white light exposure. By comparison, using the same concentration of BPD-MA or DHE, the mean recovery of normal BM progenitors was 4-5.2% for granulocyte-macrophage colony forming unit (CFU-GM) and 5-9.8% for burst forming unit erythroid (BFU-E). The T lymphoblastic leukemia cell line CEM and its vinblastine (VBL)-resistant subline CEM/VBL100, along with the acute promyelocyte leukemia cell line HL-60 and its vincristine (VCR)-resistant subline HL-60/VCR, were also tested. Our results demonstrated the preferential cytotoxicity of BPD-MA and DHE toward neoplastic cell lines and CFU-L from AML patients. In addition, DHE was slightly more effective in purging tumor cells expressing the p-170 glycoprotein.(ABSTRACT TRUNCATED AT 250 WORDS)

Availability of hematopoietic growth factors (GC-SF, GM-CSF, erythropoietin, etc.) has started a new arena of dose-intensification. The use of such growth factors has resulted in faster hematopoietic recovery of cancer patients and now offers several new treatment modifications. These include: (1)dose-intensification without hematopoietic stem cell support, (2) speedier hematopoietic recovery after hematoablative therapy and stem cell transplantation (allogeneic or autologous); (3) use of combination of growth factors, and (4) improvement in the delivery of anti-microbial drugs which are toxic towards hematopoietic cells (Gancyclovir, Bactrim, etc.). The above treatment strategies are under active clinical trials and can provide improved, cost-effective methods of treating patients with cancer.

The success of autologous stem cell transplantation using bone marrow or peripheral blood stem cells depends not only on in vivo irradication of the disease by cytotoxic therapy but also on complete hematopoietic engraftment with no risk of relapse from the infused cells. Various methods are available for removing (purging) such contaminants. Purging techniques were developed by use of various in vitro models utilizing cell lines and fresh cancer cells. Once effective conditions were developed, they were advanced onto clinical trials. Various approaches for purging have been used. Subgroups of leukemia and lymphoma have now shown clinical benefit by the use of purged stem cells. Emphasis is now being placed on utilizing the information already obtained by the pre-clinical investigators on designing better clinical trials.

The lymphokine-activated killer (LAK) phenomenon is generally referred to as nonspecific, i.e., major histocompatibility complex (MHC)-unrestricted cytotoxicity against tumor cells generated by ex vivo culture of human peripheral blood lymphocytes with interleukin 2 (IL-2). In this study, we selectively purified and depleted cell subpopulations such as natural killer (NK) cells, T-lymphocytes and monocytes from fresh human peripheral blood by negative selection. While highly purified NK cells could be induced to acquire potent LAK activity in five-day culture with IL-2, the presence of T-lymphocytes and monocytes in NK cultures was needed in order to induce a significant expansion of cytotoxic effector cells over the culture period. Neither T cells nor monocytes by themselves were able to generate LAK cells in a standard five-day IL-2 culture. However, when added to highly purified NK cells prior to IL-2 incubation, a proportion of CD3+ T-lymphocytes was found to gain LAK-like killing activity. Monocytes, when cultured with IL-2 in the presence of NK cells and T-lymphocytes, did not appear to acquire LAK activity but were able to induce a dramatic increase in cytotoxic lymphocyte recovery after five days with IL-2. In summary, we could demonstrate that peripheral blood T-lymphocytes and monocytes are potent regulators of NK-dependent lymphokine (IL-2)-activated killing.

In this paper we attempt to improve upon the methods of hematopoietic stem cell expansion. We evaluate the effects of recombinant human stem cell factor (SCF or c-kit ligand) alone and also in combination with recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin 3 (IL-3), on cell proliferation and differentiation in human long term bone marrow cultures (LTBMC). Weekly addition of 5 ng/ml of SCF with 25% serum containing media resulted in increased recovery of total nonadherent cells, granulocyte-macrophage colony forming units (CFU-GM), and burst-forming units erythroid (BFU-E) at week 1, but the number of bone marrow (BM) progenitor cells fell below the level of untreated control cultures at weeks 3 (BFU-E) and 4 (CFU-GM). At week 8, when the cultures were terminated, the CFU-GM recovery was markedly reduced in flasks supplemented with SCF compared with the controls (p < 0.002). Moreover, SCF treatment induced the early disappearance of BFU-E. When LTBMC were supplemented with the combination of SCF plus GM-CSF (100 U/ml) and IL-3 (5 ng/ml), synergistic activity of the CSFs was observed at week 1. The number of BM colony forming cells (CFC) rapidly declined below the level of growth factor-free controls, leading to the early exhaustion of the culture when SCF was combined with GM-CSF. By comparison, GM-CSF and IL-3 alone induced a statistically significant increase above the controls (no growth factor) in the number of nonadherent cell colonies of CFU-GM and BFU-E. Analysis of adherent layer cells from cultures supplemented with SCF showed increased cellularity, no adipogenesis, and early disappearance of myeloid progenitors while the percentage of CFU-GM in S phase, assessed by cytosine arabinoside (Ara-C) suicide assay, was 9.2 +/- 5% SD versus 27.7 +/- 10% SD in control (no growth factor) samples (p < 0.01). SCF increased the number of fibroblast colony forming units (CFU-F) and also showed a synergistic activity (9.6-fold increase) when combined with IL-3. These findings suggest that SCF, GM-CSF and IL-3 exert their activity on different cell populations within the hematopoietic system. Further investigations are needed to optimize the use of SCF in supporting hematopoiesis.

Thirty patients with cisplatin-refractory germ cell tumor were treated with high-dose carboplatin, etoposide, and cyclophosphamide and autologous bone marrow transplantation. The total dose of carboplatin was 1500 mg/m2, etoposide 1200 mg/m2, and cyclophosphamide was increased by increments from 60 to 150 mg/kg. Twenty-five cycles of treatment, given to 17 patients, did not include granulocyte-colony stimulating factor (G-CSF). Nineteen cycles of high-dose chemotherapy, given to 13 patients at the 2 highest dose levels of cyclophosphamide, included G-CSF. The dose of cyclophosphamide was escalated to 150 mg/kg/cycle without prohibitive toxicity. The use of G-CSF resulted in a shorter duration of neutropenia (P = 0.07); the median number of days until the recovery of an absolute granulocyte count > 0.5 was 25 without G-CSF and 14 with G-CSF. The most frequent nonhematological toxicity was hepatic, and there were 2 (7%) treatment-related deaths. Thirteen (43%) patients achieved a complete response, and 8 are alive and free of disease (27%); 7 are in continuous complete response (23%), and 1 after resection of a solitary site of disease following a relapse after high-dose chemotherapy. Five patients had pharmacology studies performed to determine the area under the curve (AUC) of free and total platinum, carboplatin, etoposide, cyclophosphamide, and phosphoramide mustard. There was a decrease in the AUC of cyclophosphamide and an increase in the AUC of phosphoramide mustard, the "active" metabolite, with successive days of treatment. The interpatient variability of the AUC of cyclophosphamide/phosphoramide mustard that was demonstrated was most likely a result of each individual's metabolic capacity. The measured AUC of carboplatin and/or free platinum closely approximated the predicted AUC of carboplatin calculated by renal function in 3 of the 5 patients. In summary, cyclophosphamide administered at a dose of 50 mg/kg x 3 days was achieved with acceptable toxicity, and no further dose escalation is planned. High-dose carboplatin, etoposide, and cyclophosphamide achieved a 23% continuous complete response proportion (27% alive, free of disease) when used as third-line therapy in germ cell tumor patients refractory to cisplatin + ifosfamide-based chemotherapy. Ongoing studies are addressing the role of high-dose carboplatin-containing chemotherapy in previously untreated patients with poor prognostic features or as a part of first-line salvage.