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F J Giles

Publications and source records attributed to F J Giles.

At least 37 records · Page 2Linked to original sources
PubMed2001

Expression of apoptosis proteins in chronic myelogenous leukemia: associations and significance.

BACKGROUND: The mechanisms favoring the growth advantage of Philadelphia chromosome positive cells over normal cells in chronic myelogenous leukemia (CML) are not fully elucidated but could be due partly to altered apoptosis and longer survival of CML clones. Also, little is known about the biologic characteristics of disease progression in CML. Bcl-2 expression has been demonstrated to exert an antiapoptotic effect resulting in increased cell survival. Other proteins such as Bax and Bad are proapoptotic proteins. Fas, a cell surface protein, can be triggered by an appropriate death-promoting ligand (FasL) to activate downstream caspases pivotal in initiation of programmed cell death. Although the mechanisms underlying cellular proliferative and apoptotic pathways are complex, with involvement of multiple interlocking proteins, the relative expression of pro- and antiapoptotic proteins may have an influence on disease progression. This study aimed to determine whether the changes in the cellular expression of Bcl-2, Bax, and Fas correlate with caspase-3 activity and disease progression in CML, or with response to interferon (IFN)-alpha therapy and prognosis in early chronic phase CML. METHODS: Bcl-2, Bax, and Fas expression were measured on whole cell lysates from bone marrow mononuclear cell fractions by Western blot analysis and quantitative radioimmunoassay. Caspase-3 activity was determined using the DEVD system. Specimens from 203 patients with CML were examined. These included 130 patients in early chronic phase disease (ECP; diagnosis to therapy, < or =12 months), 33 patients in late chronic phase (diagnosis to therapy, > 12 months), 27 patients in accelerated phase, and 13 patients in blastic phase. Correlations between apoptosis proteins and CML phases, risk groups in ECP, and response to IFN-alpha therapy and survival in ECP were investigated by standard statistical methods, and positive findings were assessed by multivariate analysis. RESULTS: Levels of Bcl-2, Fas, Bax, and caspase-3 activity did not correlate with disease progression. Among patients in ECP, higher Fas levels correlated with poorer risk groups (P = 0.05) and higher caspase-3 activity correlated with better risk groups (P = 0.048). With IFN-alpha therapy, major cytogenetic responses were noted in 30% of patients with high Fas and 53% with low Fas (P = 0.016) and failure to achieve a complete hematologic response (CHR) in 25% versus 2% (P = 0.0001). Survival was shorter with high Fas levels (5-year rates, 71% vs. 52%; P = 0.002), and the independent poor prognostic significance of high Fas levels was confirmed by multivariate analysis (P = 0.014). Response to IFN-alpha therapy and survival were not significantly different by different levels of Bcl-2, Bax, or caspase-3 activity. CONCLUSIONS: High Fas levels were associated with intrinsically worse disease at diagnosis, whereas high caspase-3 activity was associated with good risk disease. In ECP CML, high Fas levels were associated with significantly worse response to IFN-alpha therapy and with significantly worse survival. The influence of these cellular proteins and caspase-3 activity on apoptosis in CML is complex and merits further investigation.

Adolescent↗
PubMed2001

Rituximab dose-escalation trial in chronic lymphocytic leukemia.

PURPOSE: To conduct a dose-escalation trial of rituximab in patients with chronic lymphocytic leukemia (CLL) to define the maximum-tolerated dose (MTD), to evaluate first-dose reactions in patients with high circulating lymphocyte counts, and to assess the efficacy at higher versus lower doses. PATIENTS AND METHODS: Fifty patients with CLL (n = 40) or other mature B-cell lymphoid leukemias (n = 10) were treated with four weekly infusions of rituximab. The first dose was 375 mg/m(2) for all patients; dose- escalation began with dose 2 but was held constant for each patient. Escalated doses were from 500 to 2,250 mg/m(2). RESULTS: Toxicity with the first dose (375 mg/m(2)) was noted in 94% of patients but was grade 1 or 2 in most, predominantly fever and chills. Six patients (12%) experienced severe toxicity with the first dose, including fever, chills, dyspnea, and hypoxia in all six patients, hypotension in five, and hypertension in one. Toxicity on subsequent doses was minimal until a dose of 2,250 mg/m(2) was achieved. Eight (67%) of 12 patients had grade 2 toxicity, including fever, chills, nausea, and malaise, although no patient had grade 3 or 4 toxicity. Severe toxicity with the first dose was significantly more common in patients with other B-cell leukemias, occurring in five (50%) of 10 patients versus one (2%) of 40 patients with CLL (P <.001). The overall response rate was 40%; all responses in patients with CLL were partial remissions. Response rates were 36% in CLL and 60% in other B-cell lymphoid leukemias. Response was correlated with dose: 22% for patients treated at 500 to 825 mg/m(2), 43% for those treated at 1,000 to 1,500 mg/m(2), and 75% for those treated at the highest dose of 2,250 mg/m(2) (P =.007). The median time to disease progression was 8 months. Myelosuppression and infections were uncommon. CONCLUSION: Rituximab has significant activity in patients with CLL at the higher dose levels. Severe first-dose reactions were uncommon in patients with CLL, even with high circulating lymphocyte counts, but were frequent in patients with other mature B-cell leukemias in which CD20 surface expression is increased. Efficacy of rituximab was also significant in this group of patients.

Adult↗
PubMed2001

The antiangiogenic protein kinase inhibitors SU5416 and SU6668 inhibit the SCF receptor (c-kit) in a human myeloid leukemia cell line and in acute myeloid leukemia blasts.

SU5416 and SU6668 are potent antiangiogenic small-molecule inhibitors of receptor tyrosine kinases, including those of the vascular endothelial growth factor and platelet-derived growth factor receptor families. The stem cell factor (SCF) receptor, c-kit, is structurally related to these receptors and, although not expressed on mature peripheral blood cells, is expressed in leukemic blasts derived from 60% to 80% of acute myeloid leukemia (AML) patients. The c-kit kinase inhibitory activity of SU5416 and SU6668 was evaluated in MO7E cells, a human myeloid leukemia cell line. Tyrosine autophosphorylation of the receptor, induced by SCF, was inhibited in these cells by SU5416 and SU6668 in a dose-dependent manner (inhibitory concentration of 50% [IC(50)] 0.1-1 microM). Inhibition of extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation, a signaling event downstream of c-kit activation, was also inhibited in a dose-dependent manner. Both compounds also inhibited SCF-induced proliferation of MO7E cells (IC(50) 0.1 microM for SU5416; 0.29 microM for SU6668). Furthermore, both SU5416 and SU6668 induced apoptosis in a dose- and time-dependent manner as measured by the increase in activated caspase-3 and the enhanced cleavage of its substrate poly(ADP-ribose) polymerase. These findings with MO7E cells were extended to leukemic blasts from c-kit(+) patients. In patient blasts, both SU5416 and SU6668 inhibited SCF-induced phosphorylation of c-kit and ERK1/2 and induced apoptosis. These studies indicate that SU5416 and SU6668 inhibit biologic functions of c-kit in addition to exhibiting antiangiogenic properties and suggest that the combination of these activities may provide a novel therapeutic approach for the treatment of AML.

Angiogenesis Inhibitors↗
PubMed2001

Results of the fludarabine and cyclophosphamide combination regimen in chronic lymphocytic leukemia.

PURPOSE: To assess the efficacy of combination therapy with fludarabine and cyclophosphamide in patients with chronic lymphocytic leukemia (CLL) based on data suggesting in vitro synergistic activity of the two agents. PATIENTS AND METHODS: A total of 128 patients with CLL were treated with fludarabine 30 mg/m(2) intravenously daily for 3 days and cyclophosphamide at either 500 mg/m(2) daily for 3 days (n = 11), 350 mg/m(2)/d for 3 days (n = 26), or 300 mg/m(2) daily for 3 days (n = 91). The cyclophosphamide dose was decreased because of myelosuppression in the early part of the study. Patients were divided into four groups based on the expectation for response to single-agent fludarabine, including previously untreated patients, patients previously treated with alkylating agents, patients successfully treated with alkylating agents and fludarabine but relapsing, and patients refractory to fludarabine with or without alkylating agents. RESULTS: Fludarabine and cyclophosphamide produced > or = 80% response rates in all patients not refractory to fludarabine at the start of therapy as well as a 38% response rate in patients who were refractory to fludarabine. The complete remission (CR) rate was 35% in previously untreated patients, which was not significantly different from the CR rate in historical control patients treated with single-agent fludarabine. However, residual disease assessed by flow cytometry occurred in only 8% of previously untreated patients achieving CR, and median time to progression has not been reached after a median follow-up of 41 months. The main complication of therapy was related to myelosuppression and infection. Neutropenia to less than 500 x 10(9)/L was noted in 48% of patients who received cyclophosphamide 300 mg/m(2). Pneumonia or sepsis occurred in 25% of patients, and fever of unknown origin occurred in another 25%. Pneumonia or sepsis were significantly more frequent in patients who were refractory to fludarabine at the start of combination chemotherapy. CONCLUSION: Fludarabine and cyclophosphamide seem to have a significant advantage over single-agent fludarabine in the salvage setting. Although the CR rate was not increased in previously untreated patients, residual disease detected by flow cytometry was rare and remission durations seemed to be prolonged in this subset. Myelosuppression and infection remain the most significant complications of therapy in CLL.

Adult↗
PubMed2001

Troxacitabine, a novel dioxolane nucleoside analog, has activity in patients with advanced leukemia.

PURPOSE: To investigate the toxicity profile, activity, and pharmacokinetics of a novel L-nucleoside analog, troxacitabine (BCH-4556), in patients with advanced leukemia. PATIENTS AND METHODS: Patients with refractory or relapsed acute myeloid (AML) or lymphocytic (ALL) leukemia, myelodysplastic syndromes (MDS), or chronic myelogenous leukemia in blastic phase (CML-BP). Troxacitabine was given as an intravenous infusion over 30 minutes daily for 5 days. The starting dose was 0.72 mg/m(2)/d (3.6 mg/m(2)/course). Courses were given every 3 to 4 weeks according to toxicity and antileukemic efficacy. The dose was escalated by 50% until grade 2 toxicity was observed, and then by 30% to 35% until the dose-limiting toxicity (DLT) was defined. RESULTS: Forty-two patients (AML: 31 patients; MDS: six patients [five MDS + one CMML]; ALL: four patients; CML-BP: one patient) were treated. Median age was 61 years (range, 23 to 79 years), and 29 patients were males. Stomatitis and hand-foot syndrome were the DLTs. The MTD was defined as 8 mg/m(2)/d. The pharmacokinetic behavior of troxacitabine is linear over the dose range of 0.72 to 10.0 m/m(2). Approximately 69% of troxacitabine was excreted as unchanged drug in the urine. Marrow hypoplasia occurred between days 14 and 28 in 73% of AML patients. Three complete remissions and one partial remission were observed in 30 assessable AML patients. One MDS patient achieved a hematologic improvement. A patient with CML-BP achieved a return to chronic phase disease. CONCLUSION: Troxacitabine has a unique metabolic and pharmacokinetic profile and significant antileukemic activity. DLTs were stomatitis and hand-foot syndrome. Troxacitabine merits further study in hematologic malignancies.

Acute Disease↗
PubMed2001

Plasma hepatocyte growth factor is a prognostic factor in patients with acute myeloid leukemia but not in patients with myelodysplastic syndrome.

Hepatocyte growth factor (HGF) is a potent angiogenic factor. The aim of our study was to evaluate plasma HGF levels and their prognostic significance in patients with newly diagnosed acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). The sandwich enzyme immunoassay technique was used to quantify HGF in stored samples obtained before treatment from patients with AML (59 patients) and MDS (42 patients) treated at The University of Texas MD Anderson Cancer Center. HGF levels were significantly higher in patients with AML or MDS than in healthy individuals (P < 0.0001). Higher HGF levels in both AML and MDS correlated significantly with white blood cell (P = 0.000001 for both groups) and monocyte counts (P = 0.0004 and 0.003, respectively), and with poor performance status (P = 0.03 and 0.001, respectively). Using Cox proportional hazard model and HGF levels as a continuous variable, plasma levels of HGF correlated with shorter survival of AML (P = 0.001), but not MDS (P = 0.34) patients. No significant correlation was observed between HGF levels and complete remission rate or duration. In the multivariate analysis HGF retained its significance as prognostic factor in AML (P = 0.02), along with age (P = 0.0005).

Acute Disease↗
PubMed2001

Antiangiogenic therapy in leukemia.

Angiogenesis is a fundamental element of the physiological processes of embryogenesis and wound healing. During malignant transformation, dysregulation of angiogenesis leads to the formation of a vascular network of tumor-associated capillaries promoting survival and proliferation of the cancerous cells. Activation, migration, proliferation and differentiation of endothelial cells into mature blood vessels is driven by several cytokines and growth factors, known to be dysregulated in hematological malignancies. Thus, therapeutic interventions designed to eradicate the malignant clone should incorporate modulation of the angiogenic cascade. Antiangiogenic agents which target different components of the neovascularization process are being investigated in various solid tumors known to have increased vascularity. The role of angiogenesis in hematological malignancies, the rationale for the use of angiosuppressive therapy for these entities, and the status of novel antiangiogenic agents in clinical trials are discussed.

Angiogenesis Inhibitors↗
PubMed2001

The vascular endothelial growth factor (VEGF) signaling pathway: a therapeutic target in patients with hematologic malignancies.

Angiogenesis is an important component in the progression and metastasis of solid tumors. We now appreciate that angiogenesis is also critically involved in the pathogenesis of hematologic malignancies. Current data suggest important prognostic and therapeutic implications of angiogenesis in a variety of malignancies of the hematopoietic system, including acute and chronic leukemias, myeloproliferative diseases, multiple myeloma, non-Hodgkin's lymphomas, and Hodgkin's disease. Vascular endothelial growth factor (VEGF) is a major angiogenic factor that regulates multiple endothelial cell functions, including mitogenesis. Cellular and circulating levels of VEGF are elevated in hematologic malignancies and are adversely associated with prognosis. Angiogenesis is a very complex, tightly regulated, multistep process, the targeting of which may well prove useful in the creation of novel therapeutic agents. Current approaches being investigated include the inhibition of angiogenesis stimulants (e.g., VEGF), or their receptors, blockade of endothelial cell activation, inhibition of matrix metalloproteinases, and inhibition of tumor vasculature. Preclinical, phase I, and phase II studies of both monoclonal antibodies to VEGF and blockers of the VEGF receptor tyrosine kinase pathway indicate that these agents are safe and offer potential clinical utility in patients with hematologic malignancies.

Angiogenesis Inhibitors↗
PubMed2001

Cytarabine added to interferon improves the cost-effectiveness of initial therapy for patients with early chronic phase chronic myelogenous leukemia.

The French Chronic Myeloid Leukemia Study Group prospective randomized study results indicate that the addition of cytarabine to alpha interferon (IFN-alpha) increases the rate of major cytogenetic response and prolongs survival in patients with early chronic phase chronic myelogenous leukemia (CML). The French group study design permitted a single crossover to include or discontinue cytarabine or interferon. Endpoints were overall survival, complete hematologic remission (CHR) at six months, and major cytogenetic response at 12 months. We modified a published Markov model that compared IFN-alpha alone to IFN-alpha plus cytarabine and included the possibility of crossover as in the French study. The model permits allogeneic and autologous stem cell transplantation (SCT), and follows cytogenetic response and acceleration of CML through death. Treatment response, toxicity, and survival are drawn from the French Chronic Myeloid Leukemia Study Group population of 810 patients on an intention-to-treat model. Survivals are extended to 62 months based on currently available follow-up. Costs from a United States oncology specialty institution, and state utilities from previous research and a quality-adjusted Time Without Symptoms or Toxicity analysis of the subject study were discounted at 3% per annum. At the median cohort age of 50, cytarabine offers 21 months of added median survival to IFN-alpha, which itself is superior to conventional chemotherapy by 21 months. Cost-effectiveness estimates for cytarabine added to IFN-alpha range from $7,000 per quality-adjusted life year (QALY) to $35,000 per QALY, under all plausible assumptions superior to IFN-alpha alone. The model is sensitive to the quality of life on therapy, as well as to remission rate with additive cytarabine, although the cost-effectiveness calculations are robust over the entire range of clinical assumptions. Based on data from the French study, cytarabine added to IFN-alpha substantially improves the cost-effectiveness of initial therapy for early chronic phase CML.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Results of therapy with interferon alpha and cyclic combination chemotherapy in patients with philadelphia chromosome positive chronic myelogenous leukemia in early chronic phase.

The objective of the study was to investigate the toxicity and efficacy of cyclic combination therapy offered to patients with Ph-positive CML having a sub-optimal response to IFN-alpha. Patients in early chronic phase CML were treated with IFN-alpha at 5MU/m(2) daily. Patients who did not achieve cytogenetic response after 6 months of IFN-alpha therapy, or Ph-suppression to less than 35% Ph-positive cells (partial cytogenetic response) after 12 months of therapy were offered cyclic intensive chemotherapy every 6 months, with IFN-alpha maintenance between cycles. The initial 3 cycles included daunorubicin, vincristine, cytosine arabinoside (ara-C) and prednisone (DOAP). Later cycles were given with cyclophosphamide replacing daunorubicin (COAP). Of 74 patients treated, 61 (82%) achieved complete hematologic response (CHR): 51 (69%) had a cytogenetic response, which was major (Ph < 35%) in 31 (42%), and complete in 23 (31%). Fifty-five patients (74%) achieved CHR by 6 months of therapy, 38 (69%; 51% of total) with a cytogenetic response - 13 (24%) had a major cytogenetic response. Seventeen patients received at least 1 course of DOAP therapy. Median survival of the overall cohort of patients was 120 months. With a median follow-up of 145 months (103+ to 155+ months), 40 patients (54%) have died. The median duration of cytogenetic response was 35 months (range 3 to 149+ months) and the estimated 10-year cytogenetic response rate was 37%. A durable complete cytogenetic response was observed in 16 patients (20%) with a median duration of 139+ months (range 12+ to 149+ months), 11 of them (15%) are now off IFN-alpha therapy for a median of 57+ months (range 12+ to 128+ months). The projected 10-year survival was 50% for the study group versus 35% for 208 patients who received other IFN-alpha based regimens at the MD Anderson Cancer Center (p<.01). In conclusion, the addition of intensive chemotherapy may improve survival in patients with CML who have not obtained an adequate cytogenetic response on an IFN-alpha-based regimen.

Actuarial Analysis↗
PubMed2001

Fractionated cyclophosphamide, vincristine, liposomal daunorubicin (daunoXome), and dexamethasone (hyperCVXD) regimen in Richter's syndrome.

Approximately 3 to 5% of patients with chronic lymphocytic leukemia (CLL) develop an aggressive large cell non Hodgkin's lymphoma (NHL) known as Richter's syndrome (RS). RS has a poor prognosis and a response rate of < 10% with fludarabine-based or other cytotoxic combination regimens. The aim of this study was to evaluate the efficacy and toxicity of the hyperCVXD regimen in RS. Twenty-nine patients, median age 61 years (36-75) 23 males, were treated. Prior diagnosis was CLL in 26 patients, NHL in 2, and Prolymphocytic leukemia in 1. Treatment consisted of fractionated cyclophosphamide, vincristine, daunoXome and dexamethasone. Six patients (20%) died while receiving study therapy, 4 (14%) during the first cycle of whom 2 had started therapy with overt pneumonia. Grade 4 granulocytopenia occurred in all 95 cycles of therapy with a median time to recovery of 14 days. Twenty three (24%) cycles were complicated by fever, and 15 (15%) by pneumonia. Sepsis was documented in 8 (8%) cycles, and neuropathy in 5 (5%) of cycles. Twenty three patients had a platelet count < 100 x 10(9)/l prior to therapy: a greater than 50% decrease in platelet count over pre-therapy level occurred in 79% of first cycles, overt bleeding occurred in 4 (4%) of all cycles. Eleven of 29 (38%) patients achieved complete remission (CR), 4 of whom have relapsed after 5, 6, 9, and 12 months of remission. Two of 11 CR patients presented with RS without any prior CLL therapy. One patient had a partial remission. Thus the overall response rate was 12/29 (41%). Overall median survival was 10 months, 19 months in patients who achieved CR, 3 months in those who did not (p = 0.0008). A landmark analysis performed at 2 months from start of therapy comparing patients alive in CR versus patients alive but not in CR showed a median survival of 19 months versus 6 months, respectively (p 0.0017). In conclusion the hyper CVXD regimen has a relatively high response rate, significant toxicity and a moderate impact on survival in RS.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

High expression of the receptor tyrosine kinase Tie-1 in acute myeloid leukemia and myelodysplastic syndrome.

The tyrosine kinase receptor Tie-1 has been shown to play a role in angiogenesis and hematopoiesis. We evaluated the level of expression and clinical significance of Tie-1 protein in acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). We used western blot analysis to confirm and radioimmunoassay to quantify Tie-1 protein expression in bone marrow samples obtained from untreated patients having AML (66 patients) or MDS (29 patients). Samples obtained from these patients contained significantly higher levels of Tie-1 protein than did control samples (P < 0.001). Also, Tie-1 levels were significantly higher in AML patients than MDS patients (P < 0.0001). Tie-1 levels did not correlate with complete remission or survival duration in patients having either disease. These data suggest that Tie-1 expression is increased in AML and MDS but that the level of expression does not influence the response to current therapy. The role of Tie-1 overexpression in the reported increased vascularity in the bone marrow of AML and MDS patients requires further investigation.

Acute Disease↗
PubMed2001

Cost-Effectiveness of interferon alfa-2b added to chemotherapy for high-tumor-burden follicular non-Hodgkin's lymphoma.

UNLABELLED: Recent data from GELF (Groupe d'Etude des Lymphomes Folliculaires) have shown that the addition of interferon alfa-2b (IFN) to a doxorubicin-containing regimen (CHVP: cyclophosphamide, doxorubicin, teniposide and prednisone) prolongs both progression-free survival and overall survival in high-tumor-burden follicular non-Hodgkin's lymphoma. This gain must be weighed against the incremental toxicity and cost of IFN over CHVP alone and the objective here was, to determine the marginal cost-effectiveness of additive IFN in the specific setting of high-tumor-burden follicular non-Hodgkin's lymphoma. Meta-analysis of GELF trial results employing a Markov model was used with three health states: No Progression, Progressive Disease, and Death. Treatment response, survival and toxicity data are drawn from the GELF study. The current study is based on the final analysis of 242 patients (J Clin Oncol 1998;16:2332-2338), with a six year median follow-up for overall survival (median overall survival: not reached for CHVP + IFN vs 5.6 years for CHVP Only, p = 0.008). MEASUREMENTS: Quality of life data (utilities) are taken from studies with similar dosing of IFN, from Q-TwiST (quality adjusted time without symptoms or toxicity) analysis of the GELF data and from a panel of experts gathered to develop treatment models for high-tumor-burden follicular non-Hodgkin's lymphoma. Costs and quality-adjusted years of life saved were discounted at 3% per annum. SETTING: Costs determined for university medical centers in the United States. Results showed that, at the median cohort age of 52, IFN add 9.9 quality-adjusted months at an added cost of $13,900 (marginal cost-effectiveness of $16,900 per quality-adjusted life year, or QALY). A more complex, two-stage model approximates the actual cohort survival curves much better than a simple, one-stage model, but both models yield essentially the same marginal cost-effectiveness. Sensitivity analysis to quality of life on IFN shows marginal cost-effectiveness ranging from $15,200/QALY (no penalty for IFN) to $21,300/QALY (20% quality adjustment, greater than that reported). The model is quite insensitive to the probability of IFN toxicity. The model is moderately sensitive to the efficacy of IFN in delaying progression, particularly in the first 18 months (pProgI), but the marginal cost-effectiveness does not rise to $50,000/QALY until pProgI increases 220% from the baseline. Although the model is moderately sensitive to the cost of IFN (cIFN), marginal cost-effectiveness is below $50,000/QALY for values of cIFN below $2580/month (baseline cIFN = $850/month, corresponding to a marginal cost-effectiveness of $16,900/QALY in the baseline case). If the model is modified to reflect the 14% overall survival advantage at five years found in trials utilizing more intensive initial chemotherapy (including the GELF trial), then the marginal cost-effectiveness drops to $11,900/QALY in the baseline case. In condusion, based on data from the GELF study, low-dose interferon alfa-2b is cost-effective when added to CHVP therapy in the treatment of high-tumor-burden follicular non-Hodgkin's lymphoma. The analysis is robust: the model employs very conservative assumptions, and additive IFN remains cost-effective over wide ranges of variables in sensitivity analyses. The marginal cost-effectiveness is best expressed as being in the range of $12,000/QALY to $17,000/QALY in the baseline case. A simple Markov model can be used to describe treatment regimens with distinct periods of therapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Leukapheresis reduces early mortality in patients with acute myeloid leukemia with high white cell counts but does not improve long- term survival.

PURPOSE: Current published data on therapeutic leukapheresis in hyperleucocytic AML does not define the impact on survival from this procedure. Between 1992 and 1999 we saw 146 patients with newly-diagnosed AML (APL excluded) and an initial WBC count > 50 x 10(9)/L of whom 71 underwent leukapheresis at the discretion of their treating doctors. We compared outcome (early mortality, CR, and overall survival) rates in the patients who were and were not pheresed. After accounting for covariates relevant to these outcomes, including age, performance status, and cytogenetics, there was evidence (p = .006) that pheresis reduced 2-week mortality rate and a suggestion (p = .06) that this resulted in a higher CR rate. However there was no evidence that pheresis lengthened longer-term or overall survival; if anything the suggestion was the converse (p = .06). These data may reflect the fact that the patients chosen to have pheresis were prognostically unfavorable as defined by variables that were not captured in our data set, since the alternative explanation i.e. that pheresis per se shortens overall survival seems less likely. Whether the above justifies the use of pheresis in the absence of evidence from a randomized trial is doubtful, but it seems likely that any long-term benefit to be derived from this procedure must await further advances in anti-leukemia therapy.

Acute Disease↗
PubMed2000

Therapeutic choices in younger patients with chronic myelogenous leukemia.

BACKGROUND: Allogeneic stem cell transplantation (SCT) and interferon (IFN)-alpha therapy have significantly improved the prognosis of patients with Philadelphia (Ph) chromosome positive chronic myelogenous leukemia (CML). Both therapies may be suitable for younger patients. The authors reviewed current data to assist in prioritizing these modalities in an individual patient. METHODS: The authors reviewed and summarized current data on outcomes of SCT and IFN-alpha therapy in patients with early chronic phase CML. RESULTS: Several disease-, patient-, and physician-related factors affect outcomes with both modalities. Interferon-alpha does not induce myelofibrosis. The course of CML is predictable in most patients; sudden emergence of blastic phase; disease is unusual. There is no significant adverse impact of delaying SCT for the 12 months usually necessary to assess cytogenetic response to an IFN-alpha-based regimen. Interferon-alpha may be discontinued some months before SCT and is not associated with an adverse impact on post-SCT outcomes. CONCLUSIONS: An individualized risk assessment-based approach is of value in prioritizing SCT and IFN-alpha in younger patients with chronic phase CML. The authors recommend a risk-based therapy algorithm based on the expected SCT associated 1-year mortality for an individual patient.

Adult↗
PubMed2000

Homoharringtonine and low-dose cytarabine in the management of late chronic-phase chronic myelogenous leukemia.

PURPOSE: : To evaluate the efficacy and toxicity profiles of a combination regimen of homoharringtonine (HHT) and low-dose cytarabine (ara-C) in patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML) who had experienced treatment failure with interferon alfa (IFNalpha) therapy. PATIENTS AND METHODS: One hundred five patients were treated: 100 in chronic phase (15 with cytogenetic clonal evolution) and five in accelerated phase. Their median age was 52 years; all had been treated unsuccessfully with IFNalpha; 94% were in late chronic phase; 43% had been exposed to ara-C and 11% had been exposed to HHT. Patients received HHT 2.5 mg/m(2) by continuous infusion daily for 5 days and ara-C 15mg/m(2) daily in two subcutaneous injections for 5 days every 4 weeks. The outcome of the 100 patients in chronic phase was compared with a previous study group of 73 patients treated with HHT alone. RESULTS: Overall, the complete hematologic response (CHR) rate in chronic phase was 72%; the cytogenetic response rate was 32% (major response, 15%; complete response, 5%). Toxicities were acceptable, mostly related to moderate diarrhea (3%), headaches (3%), cardiovascular events (3%),and myelosuppression-associated complications (3% to 14%). With a median follow-up period of 25 months, the estimated 4-year survival rate was 55%. Response rates were identical with HHT plus ara-C versus HHT alone, but the survival was significantly longer with the combination after accounting for differences in the study groups and by multivariate analysis. CONCLUSION: The combination regimen of HHT and ara-C is effective and safe in patients with CML who have experienced treatment failure with IFNalpha and needs to be investigated together with IFNalpha as part of front-line CML therapy. The addition of ara-C did not improve the response rates but may have improved survival, perhaps through suppression of clones related to disease transformation.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Expression of thrombopoietin and its receptor (c-mpl) in chronic myelogenous leukemia: correlation with disease progression and response to therapy.

BACKGROUND: Chronic myelogenous leukemia (CML) represents a paradigm of the stepwise increment in disease aggressiveness, resistance to therapy, and transformation. Thrombopoietin (TPO) and its receptor, c-mpl, support the proliferation of multiple types of immature hematopoietic progenitor cells, and induce clonal growth of leukemic cells. The authors investigated whether TPO or c-mpl overexpression might correlate with progression of CML, disease aggressiveness, or response to therapy. METHODS: Expression of c-mpl and TPO was measured in bone marrow samples from 208 patients with CML by Western blot analysis and solid-phase plate radioimmunoassay (used for quantification). Samples obtained from individuals without evidence of hematologic abnormalities were used as controls. RESULTS: There were no significant differences in TPO or c-mpl expression among patients in different phases of CML or between patients with Philadelphia chromosome positive and negative CML. When TPO and c-mpl levels were analyzed in relation to prognostically important host and disease characteristics in early chronic phase CML, platelet and white blood cell counts demonstrated significant differences in both TPO and c-mpl expression, but age and spleen size demonstrated significant differences in TPO expression only. Responses to interferon (INF)-alpha-based therapy and survival were not influenced by TPO or c-mpl levels. CONCLUSIONS: TPO or c-mpl overexpression did not correlate with different CML phases, suggesting that they were not involved in CML progression from early to advanced phase. Neither TPO nor c-mpl overexpression was particularly evident in any risk group, suggesting lack of correlation between their expression and disease aggressiveness. This was supported by the finding of similar response to IFN-alpha-based therapy and survival regardless of the level of TPO or c-mpl expression.

Adolescent↗