Therapy of secondary acute nonlymphocytic leukemia with cytarabine

Bone Marrow Histopathology of Acute Nonlymphocytic Leukemia following Therapy for Primary Malignancies

Therapy-related acute nonlymphocytic leukemias occur with increasing frequency owing to modern aggressive antineoplastic therapies. Out of 3,138 bone marrow trephine biopsies, there were 148 cases of acute nonlymphocytic leukemias. Of these, 14 cases occurred 30–156 months following chemotherapy or radiotherapy or both for malignant disease. The male/female ratio was 0.27 (vs. 1.6 of « de novo » leukemias). Primary malignancies (7 Hodgkin's disease, 1 fibrosarcoma and 6 carcinomas) had been treated with chemotherapy+radiotherapy (10 cases), with chemotherapy alone (3 cases) or with radiotherapy alone (1 case) and were apparently cured. All therapy-related leukemias were heralded by a preleukemic cytopenic phase. Response to therapy was poor (mean survival 3.9 months). Bone marrow histopathological findings showed in 13 cases acute myelo- or monoblastic leukemia and in 1 case erythroleukemia. Out of 21 biopsies, there were increased numbers of abnormal megakaryocytes in 10, megaloblastic dyserythropoiesis in 7, and fibrosis in 13 (moderate in 11 cases and severe in 2, with dry tap). Therapy-related acute leukemia appears to be a distinct clinical-pathological entity. Bone marrow trephine biopsy is useful because of the frequency of fibrosis, the possibility of dry tap, and the characteristic histopathological findings that make diagnosis possible also in the preleukemic phase.

How I treat acute myeloid leukemia

More than one quarter of a million adults throughout the world are diagnosed annually with acute myeloid leukemia (AML). Despite considerable progress during the past 3 decades in the therapy of AML, two-thirds of young adults and 90% of older adults still die of their disease. The reported median age has increased over the past few decades, mostly because of a greater willingness of physicians to diagnose and treat older patients, and now is 72 years. The greatest challenge is in this age group. However, much improvement in therapy is needed for all adults with AML. Recent advances in allogeneic transplantation, a better understanding of prognostic factors, and development of targeted agents have only modestly improved overall outcome when large populations of patients are considered. Although an explosion in knowledge about the molecular pathogenesis of AML has outpaced treatment advances, such insights hold promise for the development of new therapies directed at specific molecular abnormalities that perturb malignant cell survival pathways. The current approach in 2010 to the management of this disease is presented through a discussion of illustrative cases.

Severe persistent cerebellar dysfunction complicating cytosine arabinoside therapy

A case of persistent cerebellar dysfunction following high-dose cytosine arabinoside (Ara-C) treatment of acute myelogenous leukemia is reported. The symptoms developed after a cumulative dose of 24 g/m2, and 6 months after the start of symptoms, the signs of cerebellar damage were unchanged. The symptoms aggravated during a subsequent low-dose therapy with Ara-C, 15 mg twice daily. This supports the presumption that this adverse effect is caused by the cumulative dose rather than by high plasma concentrations.

Toxicity and outcome of children with treatment related acute myeloid leukemia

BACKGROUND

The aim of this study was to evaluate the clinical course and outcome of children with treatment related acute myeloid leukemia (tAML) and compare them to children with primary AML (pAML).

PROCEDURE

We retrospectively reviewed the demographic, treatment, toxicity, and outcome data of children with tAML and treatment related myelodysplastic syndrome (tMDS), treated at our institution between 1975 and 2005. We compared these parameters with matched controlled children with pAML. Finally we compared overall survival (OS) for tAML with all pAML children treated at the study era in our institution.

RESULTS

Twenty-one patients with tAML (n = 19) and tMDS (n = 2) were identified. Three years event-free survival (EFS) and OS were both 14 +/- 8%. Compared to pAML patients, tAML had a higher rate of adverse cytogenetics (P < 0.008) and inferior OS (P = 0.027) but no significant difference in treatment toxicity or death. All survivors were treated with allogeneic hematopoietic stem cell transplantation (HSCT).

CONCLUSIONS

In this population based report of pediatric tAML, outcome was poor and was related to a higher probability of poor cytogenetic features rather than excessive toxicities or inability to deliver therapy. HSCT should be considered for patients with tAML. These preliminary findings should set the stage for prospective cooperative studies.

Acute myeloid leukemia

Through the hard work of a large number of investigators, the biology of acute myeloid leukemia (AML) is becoming increasingly well understood, and as a consequence, new therapeutic targets have been identified and new model systems have been developed for testing novel therapies. How these new therapies can be most effectively studied in the clinic and whether they will ultimately improve cure rates are questions of enormous importance. In this article, Dr. Jacob Rowe presents a summary of the current state-of-the-art therapy for adult AML. His contribution emphasizes the fact that AML is not a single disease, but a number of related diseases each distinguished by unique cytogenetic markers which in turn help determine the most appropriate treatment. Dr. Jerald Radich continues on this theme, emphasizing how these cytogenetic abnormalities, as well as other mutations, give rise to abnormal signal transduction and how these abnormal pathways may represent ideal targets for the development of new therapeutics. A third contribution by Dr. Frederick Appelbaum describes how AML might be made the target of immunologic attack. Specifically, strategies using antibody-based or cell-based immunotherapies are described including the use of unmodified antibodies, drug conjugates, radioimmunoconjugates, non-ablative allogeneic transplantation, T cell adoptive immunotherapy and AML vaccines. Finally, Dr. John Dick provides a review of the development of the NOD/SCID mouse model of human AML emphasizing both what it has taught us about the biology of the disease as well as how it can be used to test new therapies. Taken together, these reviews are meant to help us understand more about where we are in the treatment of AML, where we can go and how we might get there.

Biology and therapy of secondary leukaemias

Secondary leukaemias are common, accounting for more than 40% of all patients with acute myeloid leukaemia (AML) or myelodysplastic syndrome (MDS). A clinical history of exposure to haematotoxins or radiation is helpful; however, many older patients are diagnosed with leukaemia with no antecedent history of exposure. These patients' disease show a remarkably similar phenotype to classic therapy-related leukaemia. The specific cytogenetic abnormalities common to MDS, alkylating-agent-related AML and poor-prognosis AML (3q-, -5, 5q-, -7, 7q-, +8, +9, 11q-, 12p-, -18, -19,20q-, +21, t(1;7), t(2;11)), probably reflect a common pathogenesis distinct from that of other de novo AMLs, although the pathogenetic pathway has yet to be elucidated. Possibly, tumour suppressor genes are implicated and genomic instability may be a cause of multiple unbalanced chromosomal translocations or deletions. Typically, these patients are either elderly or have a history of exposure to alkylating agents or environmental exposure 5-7 years prior to diagnosis. Another distinct entity affects the mixed lineage leukaemia (MLL) gene located on 11q23. These account for about 3% of patients with therapy-related leukaemia and have a short latency period from exposure, usually to an inhibitor of topoisomerase II. Other therapy-related patients with t(8:21), inv16 or t(15;17) translocations should be treated as any other de novo AML with similar cytogenetics. In summary, the major prognostic factor is related to the pathogenetic mechanisms of the leukaemia. Cytogenetics and molecular features are a better predictor of outcome than patient history. Patients should receive standard induction therapy. However, the long-term outcome is relatively poor; the best results being obtained among patients undergoing allogeneic transplantation.

Therapy related leukemias: susceptibility, prevention and treatment

Acute leukemia is the most frequent therapy-related malignancy. Together with the increasing use of chemo- and radiotherapy, individual predisposing factors play a key role. Most of secondary leukemias can be divided in two well-defined groups: those secondary to the use of alkylating agents and those associated to topoisomerase inhibitors. Leukemias induced by alkylating agents usually follow a long period of latency from the primary tumour and present as myelodysplasia with unbalanced chromosomal aberrations. These frequently include deletions of chromosome 13 and loss of the entire or of part of chomosomes 5 or 7. The loss of the coding regions for tumor suppressor genes from hematopoietic progenitor cells is a particularly unfavourable event, since the remaining allele becomes susceptible to inactivating mutations leading to the leukemic transformation. The tumorigenic action of topoisomerase inhibitors is on the other hand due to the formation of multiple DNA strand breaks, resolved by chromosomal translocations. Among these, chromosome 11, band q23, where the myeloid-lymphoid leukemia (MLL) gene is located, is often involved. Frequent partners are chromosomes 9, 19 and 4 in the t(9;11), t(19;11) and t(4;11) translocations. Younger age, a mean period of latency of 2 years and monocytic subtypes are characteristic features of this type of leukemia. Among patients at risk for secondary leukemia, those with Hodgkin's disease are the most extensively studied, with the major impact of alkylating agents included in the chemotherapy schedule. The same is true for non-Hodgkin's lymphoma, while in multiple myeloma and acute lymphoblastic leukemia determinants are the dose of melphalan and of epypodophyllotoxin, respectively. Patients with breast, ovarian and testicular neoplasms are also at risk, in particular if trated with the association of alkylating agents and topoisomerase II inhibitors. According to the EBMT registry, in patients with lymphoma treated with high-dose therapy and autologous stem cell transplantation the cumulative risk of inducing leukemia at 5 years is 2.6%. Among treatment options, supportive therapy is indicated in older patients, while allogeneic stem cell transplantation, related or matched-unrelated, is feasible in younger patients. These data indicate the need for the identification of predisposing factors for secondary leukemia. In particular, frequent follow-up of patients at high-risk should be performed and any peripheral blood cytopenia should be considered suspicious. Whenever possible, the exclusion of drugs known to be leukemogenic from the treatment schedules should be considered, especially in young patients.

Chemotherapy of secondary leukemias

Chemotherapy of secondary leukemias is currently still considered to be associated with poor results. However, recent data suggest that the response to remission induction may substantially differ according to the previous medical history of the patients. Therapy related leukemia, arising following exposure to previous alkylating agents or radiotherapy, is often associated with chromosomal abnormalities involving chromosomes 5 and 7 and has a particularly bad response, whereas AML after exposure to epipodophyllotoxins or topoisomerase-II active agents could have a somewhat better response. Acute promyelocytic leukemia secondary to treatment of a primary malignant neoplasm seems to be associated with a better response if compared to other cytotypes of AML or to AML arising after transformation of myelodysplasia. However, here the literature data are not in full agreement, as different kinds of approaches have been applied. In fact, even if the problems encountered in treating patients with secondary leukemia are similar to those seen in patients with AML arising in a background of myelodysplasia (resistant disease and prolonged cytopenia after treatment), there are data suggesting that the use of high dose ara-C, with or without fludarabine, can circumvent resistance in a small but significant number of cases. One of the unsolved problems which still remains is how to consolidate the CR induced with high dose ara-C or with cycles based on anthracycline derivatives. In addition, another question relates to the categories of patients in whom chemotherapy may change the expected survival. Intensive post-remission chemotherapy, with or without autologous HSCT, may constitute an appropriate alternative for patients lacking a suitable sibling donor or for older patients who are in remission after chemotherapy and also able to tolerate other cycles of intensive chemotherapy. In this respect, the specific cytogenetic abnormality involved should be considered the most important prognostic factor for response and disease free survival; patients with abnormalities of chromosome 5 and 7 have a particularly low possibility of response and duration of CR. Furthermore, it is still debatable whether patients, especially the elderly, with these characteristics should go through a series of conventional treatments or just receive supportive treatment. On the other hand, patients with better prognostic factors should be entitled to further intensive treatments, taking into account possible delayed recovery and/or possible less successful collection of peripheral or marrow stem cells.

Topotecan and cytarabine is an active combination regimen in myelodysplastic syndromes and chronic myelomonocytic leukemia

PURPOSE

To evaluate the efficacy and safety of the combination of topotecan and cytarabine in patients with myelodysplastic syndromes (MDSs) and chronic myelomonocytic leukemia (CMML).

PATIENTS AND METHODS

Fifty-nine patients with MDSs and 27 with CMML were enrolled. They were either previously untreated (66%) or had received only biologic agents (14%) or chemotherapy with or without biologic agents (20%). Treatment consisted of topotecan 1.25 mg/m(2) by continuous intravenous infusion daily for 5 days and cytarabine 1. 0 g/m(2) by infusion over 2 hours daily for 5 days. Prophylaxis included antibacterial, antifungal, and antiviral agents. At a median follow-up of 7 months, all 86 patients were assessable for response and toxicity.

RESULTS

Complete remission (CR) was observed in 48 patients (56%; 61% with MDSs, 44% with CMML; P =.15). Similar CR rates were observed for patients with good-risk and poor-risk MDS (70% and 56%, respectively). The treatment effectively induced CR in patients with a poor-prognosis karyotype involving chromosomes 5 and 7 (CR, 71%) and secondary MDSs (CR, 72%). Fifty-four patients received one induction course, 25 patients received two, and the rest received more than two. The median number of continuation courses was two. The median overall duration of CR was 34 weeks (50 weeks for MDSs and 33 weeks for CMML). The median survival was 60 weeks for MDS and 44 weeks for CMML patients. CR and survival durations were longer in patients with refractory anemia with excess blasts (RAEB). Grade 3 or 4 mucositis or diarrhea was observed in three patients each. Fever was observed in 63%, and infections in 49% of patients. Six patients (7%) died during induction therapy.

CONCLUSION

Topotecan and cytarabine induced high CR rates in unselected patients with MDSs and CMML, particularly among patients with poor-prognosis cytogenetics and secondary MDSs. Topotecan-cytarabine is an active induction regimen in MDS and CMML patients, is well tolerated, and is associated with a low mortality rate.

Comparisons of prognostic scoring systems for myelodysplastic syndromes: a Korean multicenter study

We have conducted a multicenter collaborative retrospective analysis to evaluate clinical characteristics and to compare prognostic scoring systems of 149 Korean patients with myelodysplastic syndromes (MDS). The median age of the patients was 53 years (range 17-82 years) with high of the patients being younger than 40 years. Median survival was 22.6 months, and 25 patients (17%) progressed to acute myelogenous leukemia (AML) with a median interval of 6 months (range 1-45 months). Major independent variables assessed by multivariate analysis were FAB subtypes and bone marrow (BM) blast percentages for survival and BM blast percentages for AML transformation. To compare the various scoring systems in the prediction for survival and transformation to AML, FAB, Sanz and Bournemouth scoring systems were applied to all patients, while the international prognostic scoring system (IPSS), Lille and Toyama scoring systems were applied to 91 patients. The Sanz scoring system (P < 0.0001), FAB classification (P < 0.0001), IPSS (P < 0.001), and Toyama scoring system (P < 0.005) were highly predictive for survival showed greater discrimination than that of the other systems. For AML transformation, the IPSS (P < 0.0001), Toyama scoring system (P < 0.0001), FAB classification (P < 0.0001), and Lille scoring system (P < 0.005) successfully discriminated risk groups. Although the prognostic factors and the distribution of age were different from those in Western reports, the IPSS and Toyama scoring system were applicable for predicting survival and leukemic transformation in Korean patients with MDS.

Secondary leukemias induced by topoisomerase-targeted drugs

The major established cause of acute myeloid leukemia (AML) in the young is cancer chemotherapy. There are two forms of treatment-related AML (t-AML). Each form has a de novo counterpart. Alkylating agents cause t-AML characterized by antecedent myelodysplasia, a mean latency period of 5-7 years and complete or partial deletion of chromosome 5 or 7. The risk is related to cumulative alkylating agent dose. Germline NF-1 and p53 gene mutations and the GSTT1 null genotype may increase the risk. Epipodophyllotoxins and other DNA topoisomerase II inhibitors cause leukemias with translocations of the MLL gene at chromosome band 11q23 or, less often, t(8;21), t(3;21), inv(16), t(8;16), t(15;17) or t(9;22). The mean latency period is about 2 years. While most cases are of French-American-British (FAB) M4 or FAB M5 morphology, other FAB AML subtypes, myelodysplastic syndrome (MDS), acute lymphoblastic leukemia (ALL) and chronic myelogenous leukemia (CML) occur. Between 2 and 12% of patients who receive epipodophyllotoxin have developed t-AML. There is no relationship with higher cumulative epipodophyllotoxin dose and genetic predisposition has not been identified, but weekly or twice-weekly schedules and preceding l-asparaginase administration may potentiate the risk. The translocation breakpoints in MLL are heterogeneously distributed within a breakpoint cluster region (bcr) and the MLL gene translocations involve one of many partner genes. DNA topoisomerase II cleavage assays demonstrate a correspondence between DNA topoisomerase II cleavage sites and the translocation breakpoints. DNA topoisomerase II catalyzes transient double-stranded DNA cleavage and rejoining. Epipodophyllotoxins form a complex with the DNA and DNA topoisomerase II, decrease DNA rejoining and cause chromosomal breakage. Furthermore, epipodophyllotoxin metabolism generates reactive oxygen species and hydroxyl radicals that could create abasic sites, potent position-specific enhancers of DNA topoisomerase II cleavage. One proposed mechanism for the translocations entails chromosomal breakage by DNA topoisomerase II and recombination of DNA free ends from different chromosomes through DNA repair. With few exceptions, treatment-related leukemias respond less well to either chemotherapy or bone marrow transplantation than their de novo counterparts, necessitating more innovative treatments, a better mechanistic understanding of the pathogenesis, and strategies for prevention.

Treatment of children with epipodophyllotoxin-induced secondary acute myeloid leukemia

BACKGROUND

Secondary acute myeloid leukemia (AML) after treatment with epipodophyllotoxins is being observed with increased frequency. Therapeutic options are limited for patients with secondary AML and the role of bone marrow transplantation is unclear.

METHODS

The authors report the treatment outcome of a cohort of 17 children who developed epipodophyllotoxin-induced secondary AML after therapy for childhood acute lymphoblastic leukemia (ALL) that included etoposide but no irradiation or alkylating agents. Thirteen patients (76%) had 11q23 chromosomal abnormalities that were not present at the initial diagnosis of ALL.

RESULTS

Remission induction was attempted in 16 children, with 13 (81%) achieving a complete remission. After consolidation, 9 of these 13 patients received a bone marrow transplant (BMT): 2 with 4-hydroperoxycyclophosphamide-purged autologous marrow, 4 from a human leukocyte antigen (HLA)-identical sibling, 1 from a mismatched parental donor, and 2 from a matched unrelated donor. One additional child underwent allogeneic BMT without an attempt at reinduction. Of the 10 patients who received transplants, 2 were alive and well 27+ and 36+ months, respectively, after BMT. Of the 7 patients who did not receive a transplant, at last follow-up 1 had survived off therapy for 8 months for recurrent ALL whereas 6 died of AML.

CONCLUSIONS

These data confirm the poor prognosis of secondary AML after epipodophyllotoxin treatment for childhood ALL. Although patients with secondary AML can achieve a remission, it is usually of brief duration. Allogeneic BMT may offer the possibility of long term remission in some of these patients. More information is needed to better define the risks and benefits of epipodophyllotoxin therapy for childhood ALL.

The myelodysplastic syndromes in 1996: complex stem cell disorders confounded by dual actions of cytokines

Based upon recent studies of apoptosis, proliferation, cytokines and genic abnormalities, a new hypothesis regarding the pathology of myelodysplastic syndromes is being proposed. The transforming abnormality which affects an early progenitor hemopoietic stem cell is poorly defined so far but confers a growth advantage on this cell eventually leading to monoclonal hemopoiesis at least affecting the non-lymphoid bone marrow cells. Several cytokines confound the picture by exerting dual effects of stimulating the proliferation of immature cells while inducing the apoptosis in their maturing progeny thereby producing the clinical syndrome of cytopenias despite cellular marrows. Since a number of these offending cytokines share the same common lipid intracellular signalling pathway, interfering with the generation of specific phospholipid second messengers should hypothetically result in a dual effect as well. Alleviation of cytopenias (due to attenuation of apoptosis) should be accompanied by a decrease in the progeny of the transformed stem cell (due to suppression of proliferation) eventually allowing for resumption of polyclonal hemopoiesis.

A combination chemotherapy with low doses of cytarabine and etoposide for high risk myelodysplastic syndromes and their leukemic stage. A pilot study

BACKGROUND

Even now, no definitely effective therapy is inducted to high risk myelodysplastic syndromes (MDS) and their leukemic stage (MDS-AML) except bone marrow transplantation.

METHODS

Ten patients with high risk MDS and 6 with MDS-AML were treated with daily low doses of cytarabine (10 mg/m2/12h, infused over 2h) etoposide (50 mg/m2/day, infused over 2h).

RESULTS

Fourteen of these patients were finally evaluated among whom 6 with high risk MDS and 3 with MDS-AML (64.3%) had complete remission, and 2 with high risk MDS (14.3%) achieved partial remission after this chemotherapy for 9 to 21 days. Three of 11 responders were resistant to the prior chemotherapies with single and low dose cytotoxic agents including cytarabine, etoposide, or aclarubicin. Although all of the patients who could be assessed developed severe marrow hypoplasia after chemotherapy, the nonhematologic side effects were mild enough to be tolerated.

CONCLUSIONS

This combination chemotherapy must be effective and useful in high risk MDS and MDS-AML not only without prior chemotherapy but in cases which have been resistant to single and low dose oncostatic agent.

Therapy-related myeloid leukemia

One of the most serious possible consequences of cancer therapy is the development of a second cancer, especially leukemia. Several distinct subsets of therapy-related leukemia can be distinguished currently. These include classic therapy-related myeloid leukemia, leukemia that follows treatment with agents that inhibit topoisomerase II, acute lymphoblastic leukemia, and leukemias with 21q22 rearrangements or inv(16) or t(15;17). These types of leukemia are discussed in detail in this article.

Allogeneic marrow transplantation for myelodysplastic syndrome complicating autologous bone marrow transplantation

A patient with refractory relapsed Hodgkin's disease underwent an autologous bone marrow transplant in July 1987 and achieved remission of Hodgkin's disease. He had complete hematological recovery but developed pancytopenia 3 years post bone marrow transplantation with morphological evidence of myelodysplasia. High-dose cyclophosphamide, 200 mg/kg, chemotherapy followed by an allogeneic bone marrow transplant from a HLA-matched sibling was performed in April 1991 with complete hematological recovery. Allogeneic bone marrow transplantation was thus used successfully to treat a potential complication of autologous bone marrow transplantation.

Therapy-related acute myelogenous leukemia associated with 11q23 chromosomal abnormalities and topoisomerase II inhibitors: report of four additional cases and brief commentary

We report 4 additional cases of therapy-related acute myelogenous leukemia (t-AML) with the translocation t(9;11)(p22q23). Chemotherapy for the primary malignancy (breast carcinoma in 2, non-Hodgkin's lymphoma in 2) included agents with topoisomerase II inhibitory activity (doxorubicin in 2; doxorubicin and etoposide in 1; doxorubicin, etoposide and mitoxantrone in 1) as well as alkylators. In agreement with previous reports, the leukemia was monoblastic (FAB M5 subtype) in all 4 patients, with only 1 having prior myelodysplasia, and the latency period from primary therapy was relatively short (24-48 months). All patients received potentially curative treatment for the leukemia which included allogeneic bone marrow transplantation in 3; however, all died (3 of t-AML and 1 of lymphoma). Therapy-related AML associated with exposure to agents with topoisomerase II inhibitory activity (epipodophyllotoxins and anthracyclines) is a distinct entity, the genetic basis and optimal treatment of which remain to be determined.

A comparative analysis of alkylating agent and epipodophyllotoxin-related leukemias

This review deals with the differences between leukemias--induced by alkylating agents as opposed to a "new form" of treatment related leukemia due to prior exposure to epipodophyllotoxins the latter having a short treatment--disease onset interval, absence of a MDS phase, a monocytic component and cytogenetic abnormalities involving the 11q23 band. The link between the existence of oncogenes or tumor suppressor genes located on the involved portion of chromosome 11 and the development of epipodophyllotoxin-related leukemia still needs to be examined. Alkylating agents--induced leukemias have a longer treatment--disease onset interval, have a prior myelodysplastic syndrome, and are most frequent myeloblastic or myelomonocytic in nature. Karyotype analysis reveals partial or complete deletion of chromosomes no. 5 or 7. This form of leukemia is highly resistant to treatment in the majority of cases. Some of the possible molecular mechanisms of leukemogenesis are discussed.

Chemotherapy with high-dose cytosine arabinoside and mitoxantrone for poor-prognosis myeloid leukemias

Forty-seven patients with poor-prognosis myeloid leukemias received induction therapy with high-dose cytosine arabinoside (HDara-C), 1.5-3.0g/m2 for 8-10 doses, and mitoxantrone (DHAD), 12-15 mg/m2 for 3 doses. Complete remissions were achieved in 21 [45%, 95% confidence interval (CI) 30.2-59.9%] of the patients, including 11 of 14 with acute myelogenous leukemia (AML) in first relapse (79%, 95% CI 49.2-95.3%), 4 of 8 with refractory anemia with excess blasts in transformation (RAEBiT) (50%, 95% CI 15.4-84.6%), and 4 of 6 (67%, 95% CI 22.3-95.7%) previously untreated elderly AML patients. Patients with secondary AML and advanced chronic myelogenous leukemia had a very low response rate. The incidence of reversible toxicity was low and only 3 treatment-related deaths occurred. After reinduction, 8 of 9 AML patients < or = 60 years of age were ultimately able to undergo intensive therapy and either autologous 4-hydroperoxycyclophosphamide-purged bone marrow (7 patients) or peripheral blood stem cell (1 patient) transplantation with satisfactory hematological recovery. We conclude that HDara-C and DHAD is an effective antileukemic regimen in selected AML and RAEBiT patients, and that its use may allow subsequent successful autologous BMT in appropriate patients.

Mitoxantrone and intermediate-dose cytosine arabinoside for poor-risk acute leukemias: response to treatment and factors influencing outcome

Mitoxantrone (MIT, 12 mg/m2, i.v. 5 days) and intermediate-dose cytosine arabinoside (IDAC 1 g/m2/12 h, i.v. 3 days) was given to 43 patients with poor-risk acute leukemias (AL). Moderate or severe toxicity was infrequent. The proportion of complete remissions (CR) in the main patient categories was as follows: 15/18 (85 per cent) in acute myeloid leukemia (AML) in the first relapse, 2/6 in ALL in the first relapse, 0/2 in AML in relapse after bone marrow transplantation (BMT), 2/7 in AML refractory to first-line treatment (REF-AL), and 1/6 in postmyelodysplastic (PMD-AL) plus secondary AL (S-AL). The mortality rate during induction was 23 per cent. Median duration of CR was 24 weeks. The multivariate prognostic factor analysis on CR obtention showed that data concerning treatment for the first relapse and platelet count higher than the median of the series were favourable. On the contrary, PMD-AL, S-AL and REF-AL were unfavourable situations. A percentage of marrow erythroblasts superior to the median was a favourable prognostic factor for survival. Finally, the duration of CR after MIT-IDAC was directly related to the duration of previous CR. In conclusion, MIT-IDAC was highly effective to attain CR in AML in the first relapse. However, due to the poor long-term results in these patients, additional measures are recommended after CR.

Therapy of acute myelogenous leukemia

Treatment of acute myelogenous leukemia (AML) is divided into remission induction and post-remission therapy. Remission induction is usually with cytarabine and an anthracycline. Daunorubicin is commonly used but recent data suggest idarubicin or mitoxantrone are equally effective, possibly better. High-dose cytarabine has also been used for remission induction but is not proven superior. Post-remission treatment is typically with two or more courses of drugs similar to those used for remission induction. Other studies use non-cross resistant drugs and/or high-dose cytarabine. Although some data favor use of high-dose cytarabine, no approach is clearly superior. There is considerable controversy whether persons in first remission and with an HLA-identical sibling should receive a bone marrow transplant immediately or after relapse. Although transplant results appear superior, especially in persons less than 20 years of age, the most effective strategy may be reserving transplants for persons failing chemotherapy. This strategy also applies to persons receiving autologous transplants or transplants from alternative donors, like HLA-matched related or unrelated persons.

Therapy-related acute myeloid leukemia secondary to inhibitors of topoisomerase II: from the bedside to the target genes

In the past five years, several groups have reported acute myeloid leukemia (AML) often monoblastic, as a complication of chemotherapy regimens including the epipodophyllotoxins, etoposide and teniposide. This syndrome is distinct clinically, pathologically and cytogenetically from classical therapy-related myelodysplasia and AML. There is also evidence that other topoisomerase II inhibitors, such as the intercalating agents (including doxorubicin, mitoxantrone, and actinomycin D) may be leukemogenic. Furthermore, there may be further interactions from concomitant topoisomerase II inhibitors and alkylating agents. Topoisomerase II inhibitors induce DNA cleavage and other chromosomal aberrations, including sister chromatid exchanges. These clastogenic abnormalities are not fully understood, and may be specific for each cytotoxic agent. Work is in progress to clone breakpoints such as the t(9;11) and t(8;21) and the use of the resultant DNA probes will enhance our understanding of the leukemogenic process. Given the potential diversity in patients with secondary leukemia, cytogenetic studies should be mandatory for both enhancing our knowledge base and guiding treatment in individual patients. Clinicians must also be wary of the leukemogenic potential of 'dose-intense' regimens including agents such as etoposide and doxorubicin.

Management of patients with myelodysplastic syndromes

The myelodysplastic syndromes are composed of a group of clonal hematologic neoplasms, the course of which is complicated by ineffective hematopoiesis or leukemic transformation (or both). Therapeutic results may have been misleading in the past. Most patients have been managed with supportive measures, such as transfusions of erythrocytes, administration of antibiotics, and transfusions of platelets during active bleeding episodes. These supportive measures have prolonged and improved the quality of life of patients with myelodysplastic syndromes. Vitamin supplementation (folate, vitamin B12, and pyridoxine) has seldom been rewarding. Differentiation agents such as cis-retinoic acid and 1,25-dihydroxyvitamin D3 have been of benefit in only a limited number of patients. Androgens have not been useful, although danazol, which is an attenuated androgen, has been effective in a subset of patients with the presence of cell-bound platelet antibodies. Low-dose cytarabine, which has been studied extensively because of its differentiating activity in vitro, is associated with a generally low rate of complete remission and substantial toxicity. Antileukemic therapy is generally useful in young patients with rapidly progressive disease. Several hematopoietic growth factors are currently being evaluated in clinical trials; their use in combination or in conjunction with chemotherapy may be opening new horizons for these patients. With improvements in the prevention and treatment of graft-versus-host disease, allogeneic transplantation is a viable option for patients younger than 55 years of age who have severe cytopenias.

Toxicity of high-dose cytosine arabinoside in the treatment of advanced childhood tumors resistant to conventional therapy. A Pediatric Oncology Group study

Experience with high-dose cytosine arabinoside (HDAC) in pediatric solid tumors is limited. Sixteen children with solid tumors resistant to conventional therapies were registered in a pilot Pediatric Oncology Group (POG) study that required the administration of HDAC at 3 g/m2 every 12 hours for four doses. There were four cases of rhabdomyosarcoma, two cases of fibrosarcoma, four cases of neuroblastoma, and one case each of germ cell tumor, Wilm's tumor, retinoblastoma, hepatocellular carcinoma, Ewing's sarcoma, and Burkitt's lymphoma. All eligible patients had advanced diseases and had previously received extensive chemotherapy. Thirteen patients received one course of HDAC and three patients received two courses of HDAC. Due to prior treatments, patients had less than normal marrow reserves. Short-term toxicity included nausea, vomiting, suppression of hemopoiesis, drug fever, and increased blood urea nitrogen (BUN), creatinine, and liver enzymes. All evaluable patients recovered from their toxicities. There were no drug-related deaths. None of the patients had neurologic problems, including the only patient with prior irradiation to the skull. With the above schedule, HDAC appears to have manageable toxicity.

Intensive antileukemic treatment of patients younger than 65 years with myelodysplastic syndromes and secondary acute myelogenous leukemia

Intensive antileukemic treatment was evaluated in 22 patients with secondary acute myelogenous leukemia (sAML) and 14 patients with myelodysplastic syndrome (MDS). Results of combination remission-induction chemotherapy were compared with 126 patients contemporarily treated for primary AML. The duration of hypoplasia, induced by remission induction chemotherapy, tended to be longer in the sAML and MDS patients when compared to de novo AML, but reached significance only for the duration of thrombocytopenia: 26 days versus 18 days (P less than 0.01). The number of hypoplastic deaths during remission-induction chemotherapy of patients with sAML and MDS was low. Four of the 36 patients treated for sAML or MDS died during hypoplastic phases induced by remission-induction chemotherapy. The complete remission (CR) rates were similar in primary AML (67%), sAML (62%), and MDS (64%). The CR rates of patients younger than 45 years were 75% for de novo AML, 75% for sAML, and 71% for MDS. Remission rates in patients older than 45 years were identical in the three subgroups but significantly (P less than 0.005) inferior to those obtained in younger patients: 56%, 50%, and 57%, in de novo AML, sAML, and MDS, respectively. The remission duration without bone marrow transplant (BMT) was significantly shorter (P less than 0.01) in MDS and sAML when compared with primary AML. Long-lasting CR in MDS and sAML was only obtained in three of the six patients treated with allogeneic BMT. Intensive antileukemic therapy could be considered in young patients with MDS and life-threatening cytopenias or patients with sAML.

Myeloid neoplasia in children treated for solid tumours

Therapy-related myeloid neoplasia developed 14 to 189 months after diagnosis of the primary malignancy in 12 out of 3365 children treated for malignant solid tumours; 6 of the 12 were in their first complete remission. The 10-year cumulative incidence of myeloid neoplasia was 1.3% (95% Cl 0.5-3.6) for the 447 patients with Hodgkin's disease, 1.3% (0.4-4.3) for the 420 with non-Hodgkin lymphoma, and 1.2% (0.3-5.2) for the 440 with neuroblastoma. This complication appeared in 1 of 180 children with brain tumours and in none of the 1878 with other malignancies. Risk of therapy-related myeloid neoplasia in patients with Hodgkin's disease was associated with recurrence of the primary malignancy, a combination of radiotherapy and chemotherapy with alkylating agents, and age greater than or equal to 12 years at diagnosis of Hodgkin's disease. Of the 8 patients who underwent chromosomal analysis of neoplastic myeloid cells, 2 showed complete loss of chromosome 7 and 4 showed t(9;11) or t(8;21) with or without del(16)(q22). The 2 patients who had received an epipodophyllotoxin had an 11q23 abnormality. The risk of therapy-related myeloid neoplasia is low in children with malignant solid tumours.

High-dose cytosine arabinoside and L-asparaginase therapy for poor-risk adult acute nonlymphocytic leukemia. A retrospective study

The effectiveness and toxicities of high-dose cytosine arabinoside with L-asparaginase (HiDAC-ASNase) were evaluated in 41 patients with "poor risk" acute nonlymphocytic leukemia (ANLL). Twenty-four patients had either refractory or relapsed primary ANLL, and 17 had ANLL secondary to prior cytotoxic chemotherapy or an underlying hematologic disorder. The overall complete remission (CR) rate was 37%. The CR rates for primary and secondary ANLL were almost identical. Furthermore, advanced age alone did not adversely influence the CR rate. The median CR duration was 302 days with no differences between primary and secondary ANLL. The induction death rate was 24%. Predictors for induction deaths included poor initial performance status, fever at the time of presentation, low cholesterol and/or albumin, and an initial bone marrow aspirate with greater than 50% blasts. These data indicate that HiDAC-ASNase is a moderately effective regimen for patients with poor prognosis ANLL including secondary ANLL.

Allogeneic bone marrow transplantation for secondary leukaemia and myelodysplastic syndrome: a survey by the Leukaemia Working Party of the European Bone Marrow Transplantation Group (EBMTG)

This retrospective survey of the EBMT Leukaemia Working Party describes 78 patients with myelodysplasia (MDS) or secondary acute myelogenous leukaemia (sAML) who received an allogeneic bone marrow transplant (BMT). The status of underlying disease at the time of transplantation was prognostic for the 2-year disease-free survival. Thirty-four patients received intensive chemotherapy prior to the conditioning for BMT. The 2-year disease-free survival was 60% for the 16 patients transplanted in complete remission. The results were significantly less favourable for those with more advanced disease who only partially responded to prior intensive chemotherapy (2-year disease-free survival: 18%) while none of those who either relapsed or were resistant to chemotherapy survived BMT for 2 years. Forty-four patients had not received any prior intensive chemotherapy. The disease-free survival at 2 years after BMT was 58 +/- 19% when a patient was transplanted for refractory anaemia (RA(S], 74 +/- 14% for refractory anaemia with excess of blasts (RAEB), 50 +/- 16% for RAEB in transformation (RAEBt), and 18 +/- 11% for secondary AML. Allogeneic BMT can therefore be considered as curative treatment for patients with MDS. Patients with sAML who have a histocompatible donor should be given chemotherapy intensive enough to induce complete remission. If this is achieved these individuals have a prognosis comparable to those with de novo AML in first remission after BMT.

Favorable cytogenetic abnormalities in secondary leukemia

The authors report on five patients with secondary leukemia (SL) and one of the "specific" chromosomal rearrangements usually encountered in de novo acute nonlymphoblastic leukemia: inv(16), t(15;17), t(8;21), and t(9;11). They were characterized by solid tumor as the primary malignancy in four of five cases, absence of preleukemic phase in all cases, and myelodysplastic features in one of five cases only. All patients achieved complete remission (CR) with aggressive chemotherapy. Only two relapsed, but follow-up is still limited in the three remaining cases. Cytogenetic analysis is important in all younger patients with SL, especially if unusual features (such as absence of preleukemic phase or myelodysplastic features) are found. Aggressive chemotherapy appears to be indicated in those patients if a "specific" rearrangement is found.

AML associated with previous cytotoxic therapy, MDS or myeloproliferative disorders: results from the MRC's 9th AML trial

The outcome of treatment with standard first line therapy of 66 patients with acute myeloid leukaemia (AML) secondary to preceding chemotherapy (Group 1), a myelodysplastic state (Group 2) or a myeloproliferative disorder (Group 3) was analysed in relation to the preceding disorder, the cytogenetic pattern where available, and the cytology and cytochemistry of blood and bone marrow. The complete remission (CR) rate for the secondary AMLs was 36% (24/66), with 24% (16/66) dying in the induction period and 39% (26/66) having resistant disease. The CR rate was 25% (5/20) for Group 1, 42% (15/36) for Group 2, and 40% (4/10) for Group 3. Even after allowance for the generally older age of the secondary AML patients, they still had a significantly poorer CR rate than the de novo AMLs (P = 0.0004). The lower CR rate was chiefly due to resistant disease. Despite this, overall survival was not significantly worse for the secondary AML patients (P = 0.15). For the 36% that achieved remission, remission duration appeared similar to that of de novo cases. Of 62 cases with adequate cytology, 38 (61%) had evidence of erythroid and/or megakaryocytic dysplasia with a CR rate of 32% (12/38). The CR rate of these multineage leukaemias was not significantly different from that of the 24 (39%) who showed granulocyte/monocyte precursor involvement only, 42% (10) of whom achieved CR. The presence of features of differentiation within blast cells such as Auer rods or sudanophilia (greater than 50% positive blasts) was associated with a higher remission rate 47% (18/38) than that of poorly differentiated cases 17% (3/18) (P = 0.04) and thus appeared to be a more important determinant of CR achievement than was lineage involvement. Cases with a normal karyotype had a 33% (7/21) CR rate, while those with chromosomal abnormalities had a 37% (9/24) CR rate. Only 12 of the 45 cases with adequate cytogenetic analysis showed deletions or monosomies involving chromosomes 5 or 7, and seven of these were in Group 1.

Double autologous bone marrow transplantation for acute myelogenous leukemia in a patient treated for Hodgkin's disease

A 30-year-old man developed acute myelogenous leukemia nearly 3 years after treatment of Hodgkin's disease with radiation and three chemotherapy combinations. Remission was induced with one cycle of high-dose Ara-C therapy. Three cycles of consolidation chemotherapy were given. The patient then had two autologous bone marrow transplants, the first after conditioning with 5 Gy total body irradiation, the second after Melphalan 140 mg/m2. The procedures were well tolerated, although hematological reconstitution was very slow after the second autotransplant. The patient has been disease-free for over 4 years. Such patients may be more vulnerable to transplant-related complications because of their previous exposure to chemotherapy and radiation, which may damage several organs including the bone marrow. This report demonstrates that patients with secondary acute myelogenous leukemia may tolerate a double autotransplant procedure and achieve durable remissions.

Non-cardiogenic pulmonary edema complicating intermediate and high-dose Ara C treatment for relapsed acute leukemia

Infection, hemorrhage and adult respiratory distress syndrome (ARDS) are pulmonary complications occurring after remission induction therapy for acute leukemia. The aim of this study was to analyze the incidence of these causes by serial roentgenogram, clinical, microbiological and laboratory tests in 21 patients (pts) with relapsed acute leukemia (18 X myeloid, 3 X lymphoblastic), an AML-pt (acute myeloid leukemia) suffering from secondary leukemia, and three pts with primary refractory leukemia following treatment with intermediate (IM) and high-dose cytosine arabinoside (HD-Ara C), in combination with amsacrine (AMSA)(n = 19), etoposide (VP 16) (n = 5) or Mitoxantrone (n = 1). Eleven out of 25 pts developed pulmonary complications, one of them with massive hemoptysis and roentgenographic signs of pulmonary bleeding, one suffering from protracted shock after a tumor lysis syndrome, two pts showing symptoms of a cardiogenic pulmonary edema complicating severe Candida pneumonia in one case and legionnaires' disease in the other. Seven of the eleven pts had a non-cardiogenic pulmonary edema with respiratory failure 1-14 days after cessation of induction or consolidation therapy. In six of the seven, there were no signs of cardiogenic, infectious or metabolic reasons, including fluid overload, for the pulmonary edema, one had as a contributing factor a Candida infection of the lung. Three of the seven patients recovered, four died (two following IM and two after HD-Ara C). Other adverse side effects, clearly attributable to HD-Ara C, included delirious state (n = 3), generalized erythema (n = 3), acute pancreatitis (n = 2), acute abdomen (n = 1) and conjunctivitis in almost all patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute myeloblastic leukaemia in the elderly

Acute myeloblastic leukaemia (AML) is a disease of the elderly with a median age at presentation in the seventh decade and a peak incidence in the U.K. of greater than 20 patients per 100,000 population per yr between the ages of 80 and 84. Most major AML trials are carried out on a younger population of patients with low recruitment of the elderly. The results in older patients are much worse than younger patients and often no better than the natural history of the disease. These poor results may be partly due to poor tolerance of treatment in the elderly, but are also due to intrinsic differences between AML in the elderly and AML in younger patients. These problems all justify randomised, prospective trials designed specifically for elderly patients to test prognostic scoring and various levels of intensity of therapy.

Toxicity of high dose Ara-C in children and adolescents

The toxicity of high dose cytosine arabinoside (Ara-C) in 23 leukemic children aged 1.5 years to 16 years 11 months was evaluated. The group included 11 children with acute lymphoblastic leukemia (ALL), nine with acute nonlymphoblastic leukemia (ANLL), two with chronic myelocytic leukemia (CML) in blastic crisis, and one with Burkitt's lymphoma. Toxicity consisted of bone marrow suppression in all patients, with a mean nadir time of 11 days for platelets and granulocytes. All patients experienced nausea and vomiting; 12 of 23 had drug induced fever; seven of 23 conjunctivitis; five of 23 mucositis; four of 23 diarrhea, and one of 23 elevated transaminase with hyperbilirubinemia. Adverse reactions were mild and reversible in all patients. No serious neurologic toxicity was seen. The toxicity observed in four patients with prior cranial irradiation was not any different from nonirradiated patients. The only life-threatening effect was neutropenia, the consequences of which were generally well controlled with antibiotic therapy. While this agent was effective in induction of remission in AML patients resistant to standard doses of Ara-C, it had no significant effect in a very small number of patients with relapsed ALL and CML in blast crisis. Side effects of high dose Ara-C though relatively substantial are manageable enough to warrant wider scale efficacy trials of this agent in childhood leukemias and solid tumors.

Iatrogenic and idiopathic acute myelogenous leukemia: a comparison of clinical features and treatment complications

We have compared the clinical and laboratory features as well as treatment complications observed in 6 patients with iatrogenic acute myelogenous leukemia (I-AML) with those of 26 patients with idiopathic acute myelogenous leukemia (AML). I-AML patients were significantly younger and their disease appeared less virulent on admission than in the AML patients. Following identical chemotherapy, hemorrhagic complications and the need for platelet support were found to be similar for both groups. Major infections, including systemic candidiasis and Gram-negative septicemias, occurred 3 times more frequently among I-AML than AML patients. More marked suppression and delayed regeneration of the bone marrow also occurred in I-AML patients. These observations and other factors, such as post-splenectomy state and inherent immune deficiency among surgically staged lymphoma patients as well as radiation induced immunologic impairment, may have contributed to the increased propensity to develop infection observed in this group of patients. Five of the 6 I-AML and 17 of the 26 AML patients achieved remission. We attribute the satisfactory outcome in our I-AML patients to treatment in a protective environment and availability of facilities for hematologic supportive care.

Treatment-related leukemia in Hodgkin's disease: a multi-institution study on 75 cases

Hematological and cytogenetic characteristics of 75 cases of therapy-related acute non lymphoid leukemia (t-ANLL) occurring in Hodgkin's disease (HD) are analysed in this multi-institution study. Combined radio and chemotherapy had been given in 88 per cent of patients, either as adjuvant (44 per cent) or as salvage modality (44 per cent). Radiotherapy alone and chemotherapy alone had been given in 3 per cent and 9 per cent respectively. Eighty per cent of patients were in remission of HD and 71 per cent off-therapy while developing leukemia. The median latent time from remission of HD to leukemia was 34 months. The myeloblastic variety of leukemia accounted for 43 per cent of total cases; the myelomonocytic and monocytic for 17 per cent and 4 per cent, the promyelocytic and erythroblastic variants for 5 per cent and 7 per cent of t-ANLL. Twenty four per cent of cases were unclassifiable; one of these was TdT-positive. Dysplastic features of erythrocytic line were invariably present with circulating erythroblasts; defects of granulocytes, circulating megathrombocytes and micromegakaryocytes were also present. Bone marrow hypoplasia and marked fibrosis were documented in 47 per cent and 30 per cent of cases. Preleukemia heralded overt leukemia in 73 per cent of cases; 37 per cent had refractory anemia with no excess of blasts; 16 per cent of preleukemias were unclassifiable. Cytogenetics revealed chromosome abnormalities in 83 per cent of cases; 72 per cent presented chromosome 5 and/or 7 monosomy or partial deletion (5q- or 7q-) of the long arm (94 per cent in the combined modality therapy group). In 3 cases, a pure monosomy 7 was observed; in none 5q-alone. Response rate to conventional therapy was 14 per cent; low and high-dose cytarabine were of little benefit. Long-term CR (28 + and 16 + months) was achieved in 2 cases with allogeneic bone marrow transplantation (BMT) as first-line therapy. A better knowledge of t-ANLL in HD and new therapies, including BMT, may improve the prognosis of this late complication of intensive HD treatment.

In-vitro studies on phosphorylation and dephosphorylation of cytosine arabinoside in human leukemic cells

The cytotoxic effect of cytosine arabinoside (ara-C) depends on the capacity of cells to form and retain intracellularly the phosphorylated metabolite cytosine arabinoside triphosphate (ara-CTP). In this study accumulation and cellular retention of ara-CTP have been measured in vitro in the bone marrow cells of 69 patients with acute leukemia. Cells were incubated with 3H-ara-C and the amount of ara-CTP formed was determined after separation of the nucleotides by thin-layer chromatography. Phosphorylation of ara-C to ara-CTP appeared to be a saturable process. The Km-equivalents varied between 1.1 and 16.2 microM ara-C. Maximal ara-CTP formation ranged from 12 to 125 pmol ara-CTP/10(6) cells in 30 min. The phosphorylation activity did not correlate with the percentage of S-phase cells. The intracellular half-life time of ara-CTP measured in vitro ranged from 53 to 210 min. Phosphorylation of ara-C was comparable in patients with acute myeloid leukemia (n = 51) and in patients with acute lymphoblastic leukemia (n = 18). Ara-CTP elimination appeared slower in lymphoblasts than in myeloblasts. The average intracellular ara-CTP level in relapsed patients (n = 34) appeared higher than in previously untreated patients (n = 52). The less favourable outcome of second remission induction therapy with conventional doses of ara-C compared to the first remission induction treatment is not explained by an alteration in the intracellular metabolism of ara-C.