Frequency and clinical significance of BCR-ABL mutations in patients with chronic myeloid leukemia treated with imatinib mesylate.

Mutations of the BCR-ABL kinase domain are a common mechanism of resistance to imatinib in chronic myeloid leukemia. We screened for mutations 171 patients failing imatinib therapy. Sixty-six mutations in 23 amino acids were identified in 62 (36%) patients not responding to imatinib. Phosphate-binding loop (P-loop) mutations were the most frequent (n=24; 36%). By multivariate analysis, factors associated with development of mutations were older age (P=0.026) prior interferon therapy (P=0.026), and accelerated phase or blast phase at time of imatinib failure (P=0.001). After a median follow-up of 38 months (range, 4-68 months) from the start of imatinib therapy, seven patients with non-P-loop and two with P-loop mutation died. By multivariate analysis, development of clonal evolution and higher percentage of peripheral blood basophils were associated with worse survival from the time of imatinib failure. Mutation status had no impact on survival. When survival was measured from the time therapy started, non-P-loop mutations together with duration of response and transformation at the time of failure to imatinib were associated with shorter survival. In conclusion, P-loop mutations were not associated with poor outcome, suggesting that the prognosis of patients who fail imatinib is multifactorial.

Significance of cytogenetic clonal evolution in chronic myelogenous leukemia.

PURPOSE: To describe the incidence and significance of clonal evolution patterns. PATIENTS AND METHODS: We analyzed 264 patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML) who developed clonal evolution between 1967 and 1993. RESULTS: The median survival time following clonal evolution was 19 months. Factors associated with worse survival (P < .01) were as follows: chromosome 17 abnormality or chromosomal translocations other than Ph, high percentage of abnormal metaphases, longer time to clonal evolution, and presence of other accelerated-phase features. A recursive partitioning technique (CART) identified different risk groups. The best group (37 patients; no chromosome 17 abnormality, abnormal metaphases < 16%, and interval to clonal evolution < or = 24 months) had an estimated median survival time of 54 months. The worst two groups included 27 patients with chromosome 17 abnormalities and > or = 36% abnormal metaphases (estimated median survival time, 6 months), and 22 patients with other accelerated features and > or = 16% abnormal metaphases (estimated median survival time, 7 months). The intermediate group had an estimated median survival time that ranged from 13 to 24 months. Prior interferon therapy evaluated within risk groups showed a significant survival advantage only in the intermediate-risk group. A multivariate analysis showed similar results, and identified the following independent poor prognostic variables: chromosome 17 abnormality, percentage of abnormal metaphases (cutoff, 24%), longer time to clonal evolution (cutoff, 24 months), other accelerated-phase features, and no prior interferon therapy. Patients with none, one, two, three, or more of the first four features had median survivals times of 51, 24, 14, and 7 months, respectively. CONCLUSION: The prognostic significance of clonal evolution in CML is not uniform and is related to the specific abnormality, time to its development, its predominance in metaphases, and the presence of other accelerated features, and it may be modified by specific therapies.

Determinants of prognosis in late chronic-phase chronic myelogenous leukemia.

PURPOSE: Since interferon alfa (IFN-A) became an established treatment in chronic myelogenous leukemia (CML), more patients are referred to tertiary centers in late chronic phase (ie, > 12 months after diagnosis). Trials conducted in this phase cannot be evaluated precisely unless the features that determine prognosis in late chronic-phase CML are identified. The purpose of this study is to define the prognostic determinants of late chronic-phase CML. PATIENTS AND METHODS: From 1980 to 1997,257 consecutive CML patients referred in late chronic phase were studied. Their clinical characteristics at the time of referral and their association with survival were investigated. A staging model was designed. RESULTS: The median survival from time of referral was 43 months. Pretreatment characteristics associated with worse outcome included older age, poor performance status, splenomegaly, low albumin level, high percentage of blasts or basophils in peripheral blood (PB) or bone marrow, longer duration of chronic phase, and poor-risk group as defined by the Synthesis model. Prior exposure to IFN-A was not associated with worse outcome. By multivariate analysis, characteristics associated with shorter survival were age of 60 years or older, time from diagnosis of 3 years or greater, performance status of 1 or greater, PB basophils of 7% or greater, spleen 10 cm or greater, PB blasts 3% or greater, and albumin level less than 4 g/dL. A model that included age, duration of chronic phase, performance status, and PB basophils was generated. Patients with no, one, two, or three or greater adverse factors had median survivals of 71, 49, 26, and 19 months, respectively. CONCLUSION: A staging model for late chronic-phase CML can stratify patients in four groups with significantly different outcomes. If confirmed in independent populations, such a model could be considered in the analysis of future trials of treatment strategies in late chronic-phase CML.

Effect of prior interferon alfa therapy on the outcome of allogeneic bone marrow transplantation for chronic myelogenous leukemia.

PURPOSE: To determine whether prior interferon alfa (IFN-A) treatment affects the outcome of allogeneic bone marrow transplantation. PATIENTS AND METHODS: We analyzed the outcome of 77 patients with chronic myelogenous leukemia (CML) who received transplants from an HLA-identical donor using a total-body irradiation-containing preparative regimen. Engraftment, acute and chronic graft-versus-host disease (GVHD), survival, and disease-free survival were compared between patients who had previously received interferon (IFN+) to those who had not (IFN-). Forty-one patients were transplanted in chronic phase and 36 had more advanced CML. The IFN+ group had received IFN-A in doses of 3 to 5 x 10(6) U/m2 three times a week or more for at least 4 weeks anytime before transplantation. RESULTS: For patients in chronic phase, there were no significant differences between the IFN+ group and the IFN- group in regard to neutrophils recovery more than 1.0 x 10(9)/L (29 v 24), platelet recovery more than 50 x 10(9)/L (33 v 36), incidence of grade II to IV GVHD (23% v 28%), incidence of chronic GVHD (39% v 47%), disease-free survival (46% +/- 11% v 59% +/- 13%), relapse (9% v 11%), or 100-day transplant-related mortality (22% v 16%). In patients with more advanced stage disease, there was also no significant differences between the IFN+ group and the IFN- group in regard to these outcomes. CONCLUSION: Prior treatment with IFN-A did not adversely affect transplant outcome. Further studies are required to better understand the complementary roles of IFN-A and allogeneic bone marrow transplantation for the treatment of CML.

Treatment of chronic myelogenous leukemia in accelerated and blastic phases with daunorubicin, high-dose cytarabine, and granulocyte-macrophage colony-stimulating factor.

PURPOSE: The study was undertaken to improve the results of intensive chemotherapy in chronic myelogenous leukemia (CML) in accelerated (CML-AP) and blastic phases (CML-BP) by the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) as supportive therapy. PATIENTS AND METHODS: Forty-eight patients were treated with daunorubicin 120 mg/m2 intravenously on day 1, cytarabine (ara-C) 1.5 g/m2/d by continuous infusion over 24 hours for 4 days, and Solu-Medrol (methylprednisolone; The Upjohn Co, Kalamazoo, MI) 100 mg/d for 5 days, followed on day 5 by GM-CSF 125 micrograms/m2/d over 6 hours until recovery of granulocyte count above 2.0 x 10(3)/microliters. Twenty-four patients had CML-BP, and 24 had CML-AP. RESULTS: During remission induction, 45 patients (94%) developed febrile episodes (fever of unknown origin, 23 patients [48%]; documented infections, 22 patients [46%]). The median time to recovery of granulocyte count above 0.5 x 10(3)/microliters was 29 days and to platelet count above 30 x 10(3)/microliters, 28 days. Overall, 14 of 48 patients (29%) achieved a complete hematologic remission (CHR), and seven (15%) reverted to a second chronic phase. CHR was noted in eight of 24 patients with CML-BP (33%), and in six of 24 patients with CML-AP (25%). Cytogenetic responses were observed in 11 patients (23%), but were transient. Sixteen patients developed either fluid retention, hypotension, pleuropericardial effusions, or pericarditis, or a combination of these side effects. These side effects were severe in four patients and are likely to be disease-associated, as a similar regimen of intensive chemotherapy and GM-CSF at the same dose and schedule in acute lymphocytic leukemia was not associated with these side effects. CONCLUSIONS: The results pertinent to remission rates, induction mortality, myelosuppression profile and related complications, and overall survival were not significantly improved compared with previous experience. In summary, the results of intensive chemotherapy in CML-transformed phases remain poor, despite the addition of GM-CSF as a supportive measure.

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.

Collection of peripheral-blood diploid cells from chronic myelogenous leukemia patients early in the recovery phase from myelosuppression induced by intensive-dose chemotherapy.

PURPOSE: To evaluate whether intensive chemotherapy followed by peripheral stem-cell (PSC) collections during early hematopoietic recovery results in a higher percentage of diploid cell collections in patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML). PATIENTS AND METHODS: Fifty-five adults with Ph-positive CML received intensive chemotherapy with daunorubicin and high-dose cytarabine (ara-C) (DAUNO-HDAC; 26 patients) or fludarabine, high-dose ara-C, and mitoxantrone (FAM; 29 patients). Collections of the peripheral mononuclear cells were initiated when the WBC count was > or = 0.8 x 10(3)/microL. Simultaneous peripheral and marrow samples were subjected to cytogenetic studies. RESULTS: Thirty-eight of 55 patients (69%) were able to undergo the PSC collections. The rate of collection was higher in chronic phase (26 of 30 patients; 87%) than in accelerated (11 of 17; 65%) and blastic phases (1 of 8; 12%). Among the 30 patients in chronic phase, cytogenetic analyses of PSC showed cytogenetic responses (Ph-positive < 95%) in 60%, which were major (Ph < 35%) in 43% and complete (Ph = 0%) in 27%. Seven of 19 patients with simultaneous studies (37%; 23% of total) had a significantly lower percentage of Ph-positive cells in the peripheral collection compared with the marrow collection; one had the reverse phenomenon (5%; 3% of total). Cytogenetic responses were modest in both peripheral and marrow collections in CML accelerated and blastic phases. Myelosuppression-associated complications were frequent, resulting in febrile episodes in 76% of patients. CONCLUSION: PSC collection during early hematopoietic recovery from intensive chemotherapy allowed the collection of diploid-rich stem cells, mostly in chronic-phase CML. The approach could be used for in vivo purging before autologous stem-cell transplantation (ASCT).

Suppression of cytogenetic clonal evolution with interferon alfa therapy in patients with Philadelphia chromosome-positive chronic myelogenous leukemia.

PURPOSE: To investigate whether cytogenetic clonal evolution can be suppressed with interferon alfa (IFN-alpha) therapy in patients with chronic myelogenous leukemia (CML). PATIENTS AND METHODS: Ninety patients with CML and cytogenetic clonal evolution who received IFN-alpha-based regimens were analyzed. Clonal evolution was defined as the presence of karyotypic abnormalities in addition to the Philadelphia (Ph) chromosome. Patients were evaluated for the suppression of cytogenetic clonal evolution after therapy, the cytogenetic response, and survival. RESULTS: The median age of the population was 39 years (range, 15 to 70 years), median time from diagnosis to clonal evolution 14 months (range, 0 to 145 months), and median percentage of abnormal metaphases 18% (range, 4% to 100%). Fifty six patients (62%) achieved some suppression of cytogenetic clonal evolution; in 41 patients (46%), the suppression was complete. The overall median survival was 51 months, with 43% alive at 5 years. Patients who achieved a complete suppression of cytogenetic clonal evolution had a median survival of 66 months, with 51% alive at 5 years. Characteristics associated with a better response include a lower percentage of abnormal metaphases, time to cytogenetic clonal evolution of 24 months or less, and absence of other features of accelerated disease. A prognostic classification for cytogenetic clonal evolution defined three groups with complete response (CR) rates of 85%, 34%, and 0% (P < .0001) and median survival times of 58, 31, and 30 months, respectively (P=.02). CONCLUSION: Patients with cytogenetic clonal evolution can respond to IFN-alpha therapy, and this response is associated with longer survival. A previously described prognostic model separates patients into subsets with different probabilities of response to IFN-alpha and survival.

Treatment of Philadelphia chromosome-positive early chronic phase chronic myelogenous leukemia with daily doses of interferon alpha and low-dose cytarabine.

PURPOSE: To evaluate the efficacy of the combination of interferon alpha (IFN-alpha) and daily low-dose cytarabine (ara-C) in the treatment of patients with early chronic-phase chronic myelogenous leukemia (CML) (within 1 year of diagnosis). Improving the degree of hematologic and cytogenetic response in patients with Philadelphia chromosome (Ph)-positive CML may improve prognosis. Both IFN-alpha and ara-C induce cytogenetic responses as single-agent therapy in CML. PATIENTS AND METHODS: One hundred forty patients with Ph-positive early chronic-phase CML received subcutaneous injections of IFN-alpha 5 megaunits/m2 daily and ara-C 10 mg daily. Their median age was 46 years; 53% had good-risk disease, 33% had intermediate-risk disease, and 14% had poor-risk disease. Their results were compared with those of patients receiving IFN-alpha with or without intermittent ara-C (7 days/mo). RESULTS: A complete hematologic response (CHR) was achieved in 92% of patients. A cytogenetic response was seen in 74%: it was major in 50% (Ph-positive < 35%) and complete in 31% (Ph-positive 0%). With a median follow-up of 42 months, the 4-year estimated survival rote was 70% (95% confidence interval, 61% to 79%). Significant side effects included fatigue (43%; grade 3/4, 11%), weight loss (19%; grade 3/4, 11%), muscle and bone aches (20%; grade 3/4, 7%), oral ulcers (4%), diarrhea (6%), and neurologic changes (27%, grade 3/4, 6%). The median dose of IFN-alpha was 3.7 megaunits/m2 daily, mainly because of reductions for myelosuppression (70% of cases); the median ara-C dose was 7.5 mg daily. Prognostic risk groups were predictive for response to the IFN-alpha plus ara-C combination. The incidence of CHR was higher with IFN-alpha plus daily ara-C compared with IFN-alpha plus intermittent ara-C and IFN-alpha alone (no ara-C) (92% v 84% v 80%, P = .01), as were the incidences of cytogenetic response (74% v 73% v 58%; P = .003) and major cytogenetic response (50% v 38% v 38%; P = .06). The median time to achievement of major cytogenetic response was significantly shorter than that for previous IFN-alpha regimens (7 v 10 v 12 months; P < .01). However, with the present follow-up, the survival and time to blastic transformation were similar. CONCLUSION: The combination of IFN-alpha plus daily low-dose ara-C seems to be promising for the treatment of CML. High rates of CHR and cytogenetic response were observed with acceptable toxicity and a lower daily dose of IFN-alpha compared with our previous studies.

Evaluation of CI-973, a platinum analogue, in refractory or relapsed acute leukemia.

The purpose of the study was to define the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of CI-973 a new platinum analogue, in patients with refractory or relapsed acute leukemia. CI-973 was given as a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 150 mg/m2 to 1350 mg/m2 per course. Thirty-six patients were treated including 18 patients with acute myelogenous leukemia (AML), four with acute lymphocytic leukemia (ALL) and 14 with chronic myelogenous leukemia in blastic phase (CML-BP). Severe gastrointestinal and renal side-effects were the dose-limiting toxicities occurring in four of five patients treated with CI-973 1200 to 1350 mg/m2 per course. At the MTD of 1000 mg/m2 per course, three of 13 patients treated (23%) had moderate to severe nausea and vomiting, three (23%) had moderate diarrhea and one had moderate mucositis. Among 21 patients treated at > or = 1000 mg/m2 (15 AML, 6 CML-BP) no objective complete or partial responses were observed. Twelve of 18 patients (66%) with evaluable marrows on day 14 showed significant suppression of marrow blasts percentage and marrow leukemic infiltrate percentage. Tests for measurement of DNA adduct formation in leukemic cells in vivo after CI-973 therapy, and in vitro following exposure of leukemic cells to CI-973 were developed. This study defined the MTD of CI-973 to be 1000 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Gastrointestinal and renal side-effects were dose-limiting. No objective responses were noted in this heavily resistant population. Correlations between CI-973-induced DNA adduct formation and individual patient response to CI-973 will help to define its role in leukemia subsets.

Results of decitabine therapy in the accelerated and blastic phases of chronic myelogenous leukemia.

The aim of the study was to evaluate the activity of decitabine, a hypomethylating agent, in the treatment of patients with chronic myelogenous leukemia (CML) in transformation. Thirty-seven patients with CML in blastic (20 patients) or accelerated phases (17 patients) were treated. Their median age was 52 years; 36 had Philadelphia chromosome-positive disease. Decitabine was given at 100 mg/m2 over 6 h every 12 h x 10 doses (1000 mg/m2) to 13 patients, and at 75 mg/m2 over 6 h every 12 h x 10 doses (750 mg/m2) to 24 patients. In blastic phase, two patients (10%) achieved a complete hematologic response (one with Ph suppression), and three (15%) had a hematologic improvement (marrow CR, platelets <100 x 10[3]/microl), for an overall response rate of 25%. In accelerated phase, six patients (35%) returned to a second chronic phase (two with Ph suppression), one (6%) had a hematologic improvement, and two (12%) had a partial hematologic response, for an overall response rate of 53%. Prolonged myelosuppression was the most significant side-effect. The median time to recovery of granulocytes above 500/microl was 48 days, and to recovery of platelets above 30 x 10(3)/microl, 31 days. Febrile episodes occurred in 25 patients (68%) including documented infections in 17 patients (46%). Decitabine has promising activity in CML. The most significant side-effect is prolonged myelosuppression. Decitabine may show activity in other myeloid disorders such as acute myeloid leukemia and myelodysplastic syndrome, as well as in other hematologic malignancies, alone or with other drug combinations. Its value in the context of stem cell support should also be investigated.

The hyper-CVAD regimen improves outcome in relapsed acute lymphoblastic leukemia.

Sixty-six adults with refractory acute lymphocytic leukemia received salvage therapy with the 'hyper-CVAD' regimen, consisting of eight courses of alternating intensive chemotherapy with growth factor support, followed by oral maintenance chemotherapy. Their outcome was compared with 63 prognostically similar historical control patients treated with high-dose Ara-C plus mitoxantrone with or without GM-CSF. Overall, the complete response rates were similar in the treatment and control groups (29 of 66 (44%) vs 24 of 63 (38%)). There were more patients in the current study with primary resistant disease (10 of 66 (15%) vs one of 63 (2%), P = 0.006), and conversely fewer patients with secondary resistance (19 of 66 (29%) vs 28 of 63 (44%), P = 0.06). Recovery of granulocyte counts above 500/microl was significantly faster in the current study when compared to high-dose Ara-C-treated patients who were given GM-CSF (20 vs 25 days, P = 0.04). Survival was prolonged in the hyper-CVAD-treated patients, with most of the benefit seen in first salvage patients (42 vs 20 weeks, P = 0.016). When only first salvage patients were considered, there was a significant difference in disease-free survival in favor of hyper-CVAD (52 vs 20 weeks, P = 0.008). The hyper-CVAD regimen is a more effective and less toxic salvage regimen for relapsed acute lymphocytic leukemia than high-dose Ara-C-based regimens.

Serum beta-2 microglobulin levels are a significant prognostic factor in Philadelphia chromosome-positive chronic myelogenous leukemia.

Our objective was to investigate the prognostic significance of serum beta-2 microglobulin (B2M) levels among patients with chronic myelogenous leukemia (CML). All patients with Philadelphia chromosome-positive early chronic phase CML (i.e., within 1 year of diagnosis) treated with IFN alpha-based therapy at the M. D. Anderson Cancer Center between 1980 and 1997, in whom pretreatment B2M levels were available, were investigated. Two hundred one patients were evaluable. Their median B2M was 2.2 mg/dl (range, 1.1-20 mg/dl). Serum B2M levels were associated with other variables of prognostic significance, including age, spleen size, WBC count, percentage of peripheral and marrow blasts, and percentage of marrow basophils. Patients with B2M levels >2.9 mg/dl (ie., the upper quartile of the distribution) had a significantly lower rate of major cytogenetic response compared to those in the lower three quartiles (20 versus 52%; P < 0.01). They also had a shorter survival, with a 5-year survival rate of 48%, compared with 75% for those in the lower quartiles (P = 0.01). High B2M levels (>2.9 mg/dl) could identify a group of patients with an adverse outcome within patients in stage I disease (P = 0.02). Results for patients in stages 2-4 were inconclusive because of the small number of patients in these groups. We conclude that serum B2M levels are an important, and probably independent, prognostic factor for patients with CML in early chronic phase treated with IFN-based therapy.

Tallimustine, an effective antileukemic agent in a severe combined immunodeficient mouse model of adult myelogenous leukemia, induces remissions in a phase I study.

Despite progress in leukemia therapy, only 20-30% of patients with acute myelogenous leukemia (AML) are cured. 1-beta-D-arabinofuranosylcytosine- and topoisomerase II-reactive drugs are the primary therapeutic agents used. The aim of this study was to evaluate the potential activity of tallimustine in leukemia. In this study, we first investigated the efficacy and toxic effects of tallimustine, a distamycin-A derivative, in a human leukemia model in severe combined immunodeficient (SCID) mice. On the basis of its dramatic activity in this preclinical study, a Phase I study of tallimustine at a starting dose of 300 microgram/m2/day for 3 days every 3-4 weeks was conducted in patients with refractory or relapsed leukemia. In SCID mice grafted with a human myelomonocytic leukemia cell line, tallimustine resulted in complete remission of disease in most mice at tolerable dosages ranging from 0.86 to 3.0 mg/kg/day for 3 days and was combined effectively and safely with a 2-day schedule of high-dose ara-C. In the Phase I study, 26 patients with refractory or relapsed leukemia were treated. The maximum tolerated dose was 900 microgram/m2/day for 3 days every 3-4 weeks. This dose was 3 times higher than the maximum tolerated dose in solid tumors and was limited by severe mucositis. Magnesium and potassium wasting were also observed, but other side effects (fatigue and gastrointestinal) were minor. Two (8%) patients with AML achieved complete remission and two achieved hematological improvement with persistent thrombocytopenia. The results of this study indicate that tallimustine has promising activity in AML. Future studies may combine tallimustine with other agents known to be active against AML, and investigate its activity in other hematological malignancies. The recommended Phase II single-agent dose of tallimustine is 750-900 microgram/m2/day for 3 days, and combination studies may start at 50-66% of this dose schedule. The SCID mouse model of human leukemia may be promising in the preclinical evaluation and selection of potential antileukemic agents.

Significance of FHIT expression in chronic myelogenous leukemia.

Loss or reduced expression of the fragile histidine triad (FHIT) gene, a tumor suppressor gene localized at chromosome 3p14.2, is common in several solid and hematological cancers and has been associated with tumor progression and worse prognosis. The role of the FHIT gene in the pathogenesis of chronic myelogenous leukemia (CML) or its progression from a chronic phase to the accelerated and blastic phases is not known. The aim of this study was to evaluate whether Fhit protein expression is altered in CML, and whether it plays any role in CML progression, disease responsiveness to therapy, or prognosis. A total of 195 patients with Philadelphia chromosome-positive CML were evaluated, including 129 patients in early chronic phase (time from diagnosis to study, 12 months or less), 30 patients in late chronic phase, and 36 patients in the accelerated and blastic phases. The levels of cellular Fhit protein expression were determined using Western blot analysis and solid-phase RIA and compared to the levels in 31 normal marrows. The median Fhit expression in normal marrows was assigned a value of 1, and the levels in CML samples were normalized to the median of the normal control. Fhit levels in CML samples were evaluated in relation to CML phase and patient characteristics and prognosis in the early chronic phase. The median Fhit value in CML samples was 0.89 (range, 0.34-2.62). Eight of the 195 (4%) CML samples showed Fhit levels <0.5 and lacked detectable Fhit protein by Western blot. There was no difference in the levels of Fhit expression by different CML phases. In early chronic phase, reduced Fhit expression tended to be associated with leukocytosis (P = 0.04) and lower platelet counts (P = 0.01), but not with poorer-risk groups. No differences in response to IFN-alpha therapy or in survival were observed by different Fhit levels. Lack of Fhit protein expression was detected in 4% of CML cases, and reduced expression occurred in a subpopulation of patients. However, reduced Fhit expression is not associated with progression, response to therapy, or prognosis in CML.

High doses of cyclophosphamide, etoposide and total body irradiation followed by autologous stem cell transplantation in the management of patients with chronic myelogenous leukemia.

Eighteen patients with chronic myelogenous leukemia (CML) in chronic (9 patients) or advanced phases (9 patients) underwent autologous bone marrow transplantation (BMT) with a preparative regimen using high doses of cyclophosphamide, etoposide and total body irradiation (CY-VP16-TBI): cyclophosphamide 60 mg/kg daily on days 1 and 2; VP16 250 mg/m2 twice daily on days 1-3 and TBI 1020 cGy in six fractionated doses on days 5-7. Autologous marrow cells were reinfused on day 8. Three of the 8 patients in late chronic phase Philadelphia (Ph) chromosome-positive CML (37%) achieved a cytogenetic response, with Ph suppression to 25%, 29% and 44% Ph-positive metaphases, respectively, and lasting for 11, 1 and 3 months, respectively. The median duration of chronic phase following BMT was 26+ months (range 2-33+ months). One patient with Ph-negative, BCR-rearranged, chronic phase CML had a decrease of the BCR-rearranged band to 10% of pretreatment levels, which persisted for 6 months. None of the 9 patients with advanced CML phases (5 in second chronic, 1 in blastic, 3 in accelerated) achieved meaningful cytogenetic responses. Their median survival was 7 months from the time of BMT. Toxicities were mostly related to myelosuppression, particularly thrombocytopenia. Febrile episodes developed in 16 patients (89%). Treatment-related deaths occurred in 2 patients (11%). In summary, autologous BMT using a TBI-containing regimen had acceptable toxicity. Future investigations will evaluate the additional benefit of purged autologous stem cell transplantation in patients with chronic phase CML.

Fludarabine and arabinosylcytosine therapy of refractory and relapsed acute myelogenous leukemia.

There is a strong association between ability of leukemia blasts to accumulate ara-CTP, the active metabolite of ara-C, and response to ara-C in patients with relapsed or refractory AML. Ara-C dose rates in excess of 0.5 g/m2/h do not produce further ara-CTP formation. In contrast, when given 4 h prior to ara-C at this dose rate, fludarabine, at doses that are free of neurotoxicity in CLL, enhances ara-CTP accumulation. This led us to administer fludarabine and ara-C to 59 patients with AML in relapse or unresponsive to initial therapy. Fludarabine was given at 30 mg/m2 once daily for 5 doses and ara-C at 0.5 g/m2/h for 2-6 h daily for 6 doses. Doses of fludarabine preceded those of ara-C by 4 h. Results with fludarabine and ara-C (FA) were compared with those of patients treated at M.D. Anderson with high-dose ara-C (HDAC) or intermediate-dose ara-C (IDAC). The complete remission rate with FA was 21/59 (36%) and the actuarial median CR duration 39 weeks. FA produced significantly higher remission rates than HDAC or IDAC in patients with initial remissions > 1 yr (14/20 vs 9/23 vs 6/18, p < 0.05). Response rates were similar for all three treatments in patients with initial remissions < 1 yr or with primary refractory disease. The regimen was well tolerated; one patient developed peripheral neuropathy. This low level of toxicity encourages combination with other antileukemia agents.

Phase I study of arabinosyl-5-azacytidine (fazarabine) in adult acute leukemia and chronic myelogenous leukemia in blastic phase.

Fazarabine has demonstrated a broad spectrum of antitumor activity in experimental models including P388 and L1210 cell lines. Previous phase I clinical trials using a 3-day continuous infusion schedule of Fazarabine have shown myelosuppression to be the dose limiting toxicity in solid tumors. Based on this clinical and preclinical experience we designed a phase I study to determine the toxicity, maximum tolerated dose (MTD), and antileukemic efficacy of Fazarabine using a 3-day continuous infusion schedule in patients with refractory or relapsed acute leukemia or chronic myelogenous (CML) in blastic phase. Adults with a diagnosis of acute leukemia or blastic phase CML who were refractory or had relapsed on salvage chemotherapy were entered on study. Fazarabine was administered as a continuous infusion over 3 days every 3 to 4 weeks. The initial dose was 2 mg/m2/hour x 72 hours. Results showed that the MTD was 425 mg/m2/hour infused over 72 hours every 3 to 4 weeks. At this dose level neurotoxicity and fluid overload were the dose limiting toxicities. Among 71 patients treated, we observed one complete remission, one partial remission and one hematologic improvement. No obvious dose response relationship could be determined. In conclusion, Fazarabine has not shown a beneficial effect in the therapy of acute leukemia. Since 71 patients and 20 dose levels were required to determine the MTD of Fazarabine, a reassessment of our phase I study designs should be considered to provide patients with better potential toxic: therapeutic benefits in such trials.

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.

Unexpected high incidence of severe toxicities associated with alpha interferon, low-dose cytosine arabinoside and all-trans retinoic acid in patients with chronic myelogenous leukemia.

Preclinical data have shown that all-trans retinoic acid (ATRA) with interferon-alpha (IFN-alpha) can exert significant suppressive effects on Philadelphia-chromosome (Ph)-positive cells. The aim of this study combining IFN-alpha, low-dose cytosine arabinoside (ara-C) and ATRA was to increase the proportion of patients achieving a major cytogenetic response, in comparison with a group of 140 patients previously treated with IFN-alpha plus low-dose ara-C. Forty three patients with Ph-positive CML in early chronic phase were treated with IFN-alpha 5 MU/m2 s.c. daily, low-dose ara-C 10 mg s.c. daily and ATRA 45 mg/m2 orally daily, for 7 consecutive days every other week. Overall, 76% of patients achieved a complete hematologic response (CHR). A cytogenetic response was in observed 59% (major in 38% and complete in 17%). Compared with patients treated with IFN-alpha and low-dose ara-C, those receiving additional ATRA had a lower CHR rate (p. 014), but other response rates were similar. Severe toxicities were common with the triple regimen (64%), mostly related to ATRA therapy. Two patients experienced pseudotumor cerebri; two patients had leukocytosis during the week on ATRA treatment, decreasing during the week off (one suffered a severe asthma-like reaction followed by pulmonary edema, resembling ATRA syndrome). Six patients had other unusual side-effects: aseptic necrosis of the hip (1 patient), ataxic syndrome (1 patient), paranoid syndrome (2 patients), syncopal episodes (1 patient), pure red cell aplasia (1 patient). In conclusion the results of IFN-alpha and low-dose ara-C combined with ATRA in patients with early CML-chronic phase were disappointing, due to excessive toxicity. Whether different ATRA dose schedules may result in fewer side-effects and improve hematologic and cytogenetic response remains to be determined.