Induction therapy by frequent administration of doxorubicin with four other drugs, followed by intensive consolidation and maintenance therapy for adult acute lymphoblastic leukemia: the JALSG-ALL93 study

Impact of a donor source on adult Philadelphia chromosome-negative acute lymphoblastic leukemia: a retrospective analysis from the Adult Acute Lymphoblastic Leukemia Working Group of the Japan Society for Hematopoietic Cell Transplantation

BACKGROUND

We aimed to clarify the impact of the donor source of allogeneic stem cell transplantation (allo-SCT) on Philadelphia chromosome-negative acute lymphoblastic leukemia [Ph(-) ALL] with focus on cord blood (CB).

PATIENTS AND METHODS

We retrospectively analyzed data of 1726 patients who underwent myeloablative allo-SCT for adult Ph(-) ALL. The sources of the allo-SCT were related donors (RD; N = 684), unrelated donors (URD; N = 809), and CB (N = 233).

RESULTS

Overall survival (OS) in patients after CB allo-SCT in first complete remission (CR1) was comparable with that after RD or URD allo-SCT (RD: 65%, URD: 64% and CB: 57% at 4 years, P = 0.11). CB was not a significant risk factor for relapse or non-relapse mortality as well as for OS in multivariate analyses. Similarly, the donor source was not a significant risk factor for OS in subsequent CR or non-CR (RD: 47%, URD: 39% and CB: 48% in subsequent CR, P = 0.33; RD: 15%, URD: 21% and CB: 18% in non-CR, P = 0.20 at 4 years).

CONCLUSION

Allo-SCT using CB led to OS similar to those of RD or URD in any disease status. To avoid missing the appropriate timing, CB is a favorable alternative source for adult Ph(-) ALL patients without a suitable RD or URD.

Treatment of adults with acute lymphoblastic leukemia: do the specifics of the regimen matter?: Results from a prospective randomized trial

BACKGROUND

Induction therapy for adults with acute lymphoblastic leukemia (ALL) is similar across essentially all regimens, comprised of vincristine, corticosteroids, and anthracyclines intensified with cyclophosphamide, asparaginase, or both. Given the lack of randomized data, to date, no regimen has emerged as standard. The authors previously evaluated cytarabine 3 g/m(2) daily for 5 days with mitoxantrone 80 mg/m(2) (the ALL-2 regimen) as a novel induction regimen. Compared with historic controls, the ALL-2 regimen was superior in terms of incidence of complete remission, failure with resistant disease, and activity in patients with Philadelphia chromosome (Ph)-positive ALL.

METHODS

The authors conducted a multicenter, prospective, randomized trial of the ALL-2 regimen compared with a standard 4-drug induction (the L-20 regimen). Patients also received consolidation, maintenance therapy, and central nervous system prophylaxis. The trial accrued patients from August 1996 to October 2004.

RESULTS

The median follow-up for survivors was 7 years, and the median patient age was 43 years. Responses were evaluated in 164 patients. The treatment arms were balanced in terms of pretreatment characteristics. The frequency of complete remission for the ALL-2 regimen versus the L-20 regimen was 83% versus 71% (P = .06). More patients on the L-20 arm failed with resistant disease (21% vs 8%; P = .02). Induction deaths were comparable at 9% (ALL-2) versus 7% (L-20). The median survival was similar; and, at 5 years, the survival rate was 33% alive on the ALL-2 arm versus 27% on the L-20.

CONCLUSIONS

Despite superior results of induction therapy with the ALL-2 regimen, this treatment did not improve long-term outcomes. When coupled to the reported experience of other studies in adults with ALL, the results of this randomized trial raise the possibility that ultimate outcomes in adult ALL may be independent of the specific regimen chosen. Cancer 2013. © 2012 American Cancer Society.

Allogeneic, but not autologous, hematopoietic cell transplantation improves survival only among younger adults with acute lymphoblastic leukemia in first remission: an individual patient data meta-analysis

Hematopoietic cell transplantation (HCT) and prolonged chemotherapy are standard postremission strategies for adult acute lymphoblastic leukemia in first complete remission, but the optimal strategy remains controversial. There are no randomized trials of allogeneic HCT. In the present study, updated individual patient data were collected and analyzed from studies with information on availability of matched sibling donor (used to mimic randomization) and from randomized trials of autograft versus chemotherapy. Data from 13 studies including 2962 patients, excluding Philadelphia chromosome-positive patients, showed a survival benefit for having a matched sibling donor for patients < 35 years of age (OR = 0.79; 95% CI, 0.70-0.90, P = .0003) but not for those ≥ 35 years of age (OR = 1.01; 95% CI, 0.85-1.19, P = .9; heterogeneity P = .03) because of the higher absolute risk of nonrelapse mortality for older patients. No differences were seen by risk group. There was a trend toward inferior survival for autograft versus chemotherapy (OR = 1.18; 95% CI, 0.99-1.41; P = .06). No beneficial effect of autografting was seen compared with chemotherapy in this analysis. We conclude that matched sibling donor myeloablative HCT improves survival only for younger patients, with an absolute benefit of approximately 10% at 5 years. Improved chemotherapy outcomes and reduced nonrelapse mortality associated with allogeneic HCT may change the relative effects of these treatments in the future.

The role of allogeneic hematopoietic stem cell transplantation in the therapy of patients with acute lymphoblastic leukemia

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is an effective post-remission therapy in patients with acute lymphoblastic leukemia (ALL), but is associated with significant toxicity, so the optimal timing and use of this modality remains an issue of debate. Increased advances in reduced-intensity transplant preparative regimens and alternative donors has increased the accessibility of allogeneic transplantation. A risk adapted paradigm, using minimal residual disease analysis, may help in the selection of patients at highest risk for relapse, who may benefit most from alloHSCT. In this review, we summarize the indications for allogeneic transplantation within the risk-oriented paradigm, and also explore the latest literature on reduced intensity transplant regimens, as well as alternative donor transplantation for patients with ALL.

Prognostic factors influencing clinical outcome of allogeneic hematopoietic stem cell transplantation following imatinib-based therapy in BCR-ABL-positive ALL

We investigated prognostic factors for the clinical outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) following imatinib-based therapy. Among 100 adult patients who were prospectively enrolled in the JALSG Ph+ALL202 study, 97 patients obtained complete remission (CR) by imatinib-combined chemotherapy, among whom 60 underwent allo-HSCT in their first CR. The probabilities of overall survival (OS) and disease-free survival (DFS) at 3 years after HSCT were 64% (95% CI, 49–76) and 58% (95% CI, 43–70), respectively. Prognostic factor analysis revealed that the major BCR–ABL transcript was the only unfavorable predictor for OS and DFS after HSCT by both univariate (HR, 3.67 (95% CI 1.49–9.08); P=0.005 and HR, 6.25 (95% CI, 1.88–20.8); P=0.003, respectively) and multivariate analyses (HR, 3.20 (95% CI, 1.21–8.50); P=0.019 and HR, 6.92 (95% CI, 2.09–22.9); P=0.002, respectively). Minimal residual disease status at the time of HSCT had a significant influence on relapse rate (P=0.015). Further study of the BCR–ABL subtype for the clinical impact on outcome of allo-HSCT in Ph+ALL is warranted.

Aberrant methylation and decreased expression of the RIZ1 gene are frequent in adult acute lymphoblastic leukemia of T-cell phenotype

Retinoblastoma protein-interacting zinc finger, RIZ1, is a tumor suppressor gene that is inactivated in various solid tumors. However, the role of the RIZ1 gene has not been well examined in adult acute lymphoblastic leukemia (ALL). We analyzed the expression and promoter methylation status of the RIZ1 gene in patients with newly diagnosed ALL by quantitative real-time reverse transcription polymerase chain reaction (PCR) and methylation-specific PCR, respectively. RIZ1 expression in 67 cases of ALL (mean 1.043) was decreased compared with that in normal bone marrow (mean 1.471) (p = 0.030). Methylation was detected in 11 of 71 patients (15.5%) but not in healthy controls. Methylation was associated with decreased RIZ1 expression in many ALL cases examined, but this was not statistically significant. In T-ALL, RIZ1 methylation was more frequent (63.6%) than in B-ALL (6.7%) (p < 0.0001) and the decrease of RIZ1 expression was more significant than in B-ALL (p = 0.045). 5-Aza-2'-deoxycytidine treatment of MOLT-4 cells with RIZ1 methylation induced demethylation of RIZ1 and restoration of expression. Forced RIZ1 expression in T-ALL cell lines suppressed cell growth accompanied by G2/M arrest and apoptosis. No mutations were found by PCR-single strand conformation polymorphism analysis in hotspots of the gene. These results suggest that RIZ1 is inactivated in adult ALL, and this inactivation is associated with methylation in T-ALL.

The study of resistant mechanisms and reversal in an imatinib resistant Ph+ acute lymphoblastic leukemia cell line

In this study, we established an imatinib resistant Ph+ acute lymphoblastic leukemia (ALL) cell line SUP-B15/RI in vitro and studied the mechanism of imatinib resistance. Our results showed that the BCR-ABL1 fusion gene and the mdr1 gene were 6.1 times and 1.7 times, respectively, as high as that of parental SUP-B15 cell line. We found no mutation in the Abl kinase domain of SUP-B15/RI. Furthermore, the detection of cell signaling pathway of PI3K/AKT/mTOR, RAS/RAF, NF-κB, JNK and STAT showed the up-regulation of phosphorylation of AKT, mTOR, P70S6K, and RAF, ERK, and MEK, down-regulation of PTEN and 4EBP-1, and no change in other cell signaling pathways in SUP-B15/RI. However, dasatinib and nilotinib showed partial resistance. Interestingly, bortezomib had no resistance. Imatinib combination with rapamycin had synergistic effect on overcoming the resistance. Altogether, over-expression of BCR-ABL1 and mdr1 gene were involved in the resistance mechanisms, and up-regulation of the cell signaling pathways of PI3K/AKT/mTOR, RAS/RAF in SUP-B15/RI cell line may be correlated with them. The SUP-B15/RI cell line was also resistant to the second generation tyrosine kinase, dasatinib, and nilotinib, not bortezomib. The combination of imatinib with rapamycin can partially overcome the resistance and blockade of the ubiquitin-proteasome can be also a promising pathway to overcome imatinib resistance.

Treatment of acute lymphoblastic leukemia in adolescents and young adults

Treatment approaches for adolescents and young adults with acute lymphoblastic leukemia (ALL) have evolved considerably in the past 5-7 years. One of the major changes has been the widespread adoption of pediatric-based protocols, which appears to have significantly improved survival and probably renders allogeneic hematopoietic stem cell transplantation (HSCT) unnecessary in most standard-risk patients. However, high-risk patients, such as those with BCR-ABL or MLL rearrangements or high white count presentations, should still be referred for HSCT in CR-1. Minimal residual disease positivity has also been identified as a high-risk feature. Patients with BCR-ABL-positive ALL should receive combined therapy with a tyrosine kinase inhibitor and chemotherapy prior to HSCT. The adoption of pediatric-based regimens has been associated with significant additional toxicities, including venous thromboembolism, osteonecrosis, other steroid-related changes, and neuropathy, which can potentially have a major adverse impact on the quality of life of these young ALL patients.

Allogeneic hematopoietic cell transplantation for adult acute lymphoblastic leukemia (ALL) in first complete remission

BACKGROUND

Consolidation chemotherapy, autologous hematopoietic cell transplantation (HCT) and allogeneic HCT represent potential treatment alternatives for post-remission therapy in adult acute lymphoblastic leukemia (ALL), but there is genuine uncertainty regarding the optimal approach.

OBJECTIVES

To assess the effect of matched sibling donor vs. no donor status for adults with ALL in first complete remission (CR1).

SEARCH STRATEGY

We performed a search of CENTRAL, MEDLINE and EMBASE electronic databases in September 2010 along with handsearching of literature cited in relevant primary articles, search of abstracts from American Society of Hematology and American Society of Clinical Oncology meetings, as well as consultation with content experts in the field.

SELECTION CRITERIA

Review was performed by two authors, and Inclusion criteria included the following: controlled trials with donor vs. no donor comparison with assignment by genetic randomizationin adults with ALL in CR1.

DATA COLLECTION AND ANALYSIS

We extracted data on benefits (overall survival, progression-free survival) and harms (treatment-related mortality, relapse) of compared treatments. Adverse events were considered, but analysis of individual adverse events was not possible from the reported literature. We pooled summary results from each study using a random-effects model. We assessed heterogeneity. We performed subgroup analyses for disease risk categories. We performed sensitivity analyses according to methodological quality.

MAIN RESULTS

A total of 14 relevant trials were identified, consisting of a total of 3157 patients. There was a statistically significant overall survival advantage in favor of the donor versus no donor group (HR 0.86; 95% CI 0.77 to 0.97; P = 0.01), as well as significant improvement in disease-free survival in the donor group(HR 0.82; 95% CI 0.72 to 0.94; P = 0.004). Those in the donor group had significant reduction in primary disease relapse(RR 0.53; 95% CI 0.37 to 0.76; P = 0.0004) and significant increase in non-relapse mortality(RR 2.8; 95% CI 1.66 to 4.73; P = 0.001). Significant heterogeneity was detected in analysis of relapse (Chi(2) 40.51, df = 6, P < 0.00001; I(2) = 85%). In regard to methodologic quality, the majority of included studies were free of selective reporting, and performed analyses according to intention to treat. Conversely, few reported sample size calculation that informed the study design. While blinding was considered as an important domain of methodological quality, none of the studies reported on whether any of the study personnel were blinded (e.g. subjects, personnel, outcome assessors, data analysts etc). Therefore, we did not consider blinding further in the analysis of methodological quality in this review.

AUTHORS' CONCLUSIONS

The results of this systematic review and meta-analysis support matched sibling donor allogeneic hematopoietic cell transplantation as the optimal post-remission therapy in ALL patients aged 15 years or over. This therapy offers superior overall survival and disease-free survival, and significantly reduces the risk of disease relapse, but does impose an increased risk of non-relapse mortality. Importantly these data are based on adult ALL treated with largely total body irradiation-based myeloablative conditioning and sibling donor transplantation and, therefore, cannot be generalized to pediatric ALL, alternative donors including HLA (human leukocyte antigen) mismatched or unrelated donors, or reduced toxicity or non-myeloablative conditioning regimens.

A potential role of ruxolitinib in leukemia

INTRODUCTION

An increased understanding of cellular signaling pathways, like the JAK?STAT pathway, and the identification of the JAK2 V617F mutation in the classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), has generated great interest in the development of targeted JAK2 inhibitors. In a recently completed Phase I?II study, ruxolitinib, a selective orally available JAK1 and JAK2 inhibitor, has shown efficacy in patients with advanced myelofibrosis. Constitutive activation of the JAK?STAT pathway has also been implicated in other hematological malignancies suggesting a potential role of JAK kinase inhibitors in these malignancies.

AREAS COVERED

This article reviews the chemistry, pharmacodynamics, pharmacokinetics, clinical efficacy, safety and tolerability of ruxolitinib. The literature for this article was retrieved from PubMed database searches using the keywords ?ruxolitinib?, ?INCB 018424?, ?JAK2 inhibitors? and ?leukemia?.

EXPERT OPINION

The JAK?STAT signaling pathway plays a vital role in leukemogenesis. Ruxolitinib, a potent JAK1 and JAK2 inhibitor, known to decrease spleen size and alleviate constitutional symptoms in myelofibrosis, represents a potentially promising agent for the treatment of leukemias by inhibiting the JAK?STAT signaling. Further studies of ruxolitinib, in patients with acute and chronic leukemias, are now needed to establish the clinical usefulness of this promising drug.

The role of allogeneic stem cell transplantation for adult acute lymphoblastic leukemia

Acute lymphoblastic leukemia remains a challenging disease in adults. With modern multi-drug induction chemotherapy regimens, complete remission can be achieved in most patients. However, without additional therapy at the time of the first remission, most patients will eventually relapse. Regardless of the treatment option chosen at the time of relapse, outcomes after relapse are poor, with only around 10% of all patients surviving after relapse. Thus, decision-making at the time of achieving the first complete remission is critical. Allogeneic stem cell transplantation is highly effective at preventing relapse, but with significant treatment related toxicity. Ongoing chemotherapy in the form of consolidation and maintenance may be less effective at preventing relapse, but with lower toxicities. Thus, the superiority of allogeneic stem cell transplantation must be balanced against the lower toxicity of consolidation chemotherapy. This decision is further complicated by rapid changes in the field of hematopoietic stem cell transplantation, such as the use of reduced intensity conditioning regimens and alternative stem cell sources such as cord blood transplants. The available evidence suggests that allogeneic transplantation is a viable treatment option for patients in first complete remission, with overall survival superior to traditional consolidation and maintenance chemotherapy. However, whether transplantation based post-remission therapy is superior to modern, pediatric-based non-transplant chemotherapy regimens remains unclear.

Modern Therapy of Acute Lymphoblastic Leukemia

Although acute lymphoblastic leukemia is curable in one third of adult patients, results vary greatly on account of different clinical, immunologic, and cytogenetic/genetic characteristics. These data, along with the kinetics of response to early treatment, help establish the individual risk class with considerable accuracy, and support risk-specific treatments that should warrant optimal results with as little as possible nonrelapse mortality. Modern first-line therapy consists of standard- and high-dose chemotherapy (increasingly inspired to pediatric principles), hematopoietic stem-cell transplantation, and new targeted therapy, all integrated with the analysis of prognostic factors and the study of subclinical residual disease for key therapeutic decisions. These changes are improving long-term outcome, which in ongoing studies is expected close to 50% or greater.

Changing paradigm of the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia

In the pre-imatinib era, the treatment outcome of patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) was dismal. Complete remission was generally achieved only in about 50% to 60% of patients, and allogeneic hematopoietic stem cell transplantation (allo-HSCT), when feasible in younger patients, was virtually the sole curative modality. Imatinib has changed the situation dramatically, however, in combination with conventional chemotherapy or with corticosteroid alone, producing about 95% complete remission and thus increasing the number of patients undergoing allo-HSCT. Currently, the overall survival of patients who have undergone allo-HSCT exceeds 50%, and a considerable proportion of patients for whom allo-HSCT is not feasible are predictably curable. The next question is how to prevent relapse, which is observed not only in more than half of patients for whom allo-HSCT is not feasible but also in a considerable number of patients after allo-HSCT. Thus, improvement of postremission therapy is crucial. Whether intensive chemotherapy with currently available cytotoxic drugs contributes to the prevention of relapse is questionable, because intensive chemotherapy alone in the pre-imatinib era nearly always failed to cure this disease. Promising partners to be combined with imatinib or with a second-generation tyrosine kinase inhibitor (TKI) will be corticosteroids and vincristine. New TKIs such as dasatinib should be incorporated into the early phase of postremission therapy. Recognizing the small number of patients with Ph(+) ALL, intergroup or international studies are necessary to develop the best postremission therapy. In the near future, it is hoped that Ph(+) ALL will become one of the leukemias for which allo-HSCT is offered only for relapsed or extremely high-risk patients.

Successful treatment of necrotizing fasciitis in an upper extremity caused by Clostridium perfringens after bone marrow transplantation

We report a 47-year-old man with acute leukemia who survived a severe case of necrotizing fasciitis caused by Clostridium perfringens involving his right upper extremity. On day 5 after stem cell transplantation, progressive local tissue necrosis led to septicemia and disseminated intravascular coagulation. Early diagnosis and prompt initiation of appropriate therapy, including surgical debridement and broad-spectrum antibiotics, were crucial. A recombinant thrombomodulin might have not only resolved the coagulation problem but also prevented multiple organ failure associated with the systemic inflammatory response.

Pre-transplant imatinib-based therapy improves the outcome of allogeneic hematopoietic stem cell transplantation for BCR-ABL-positive acute lymphoblastic leukemia

A high complete remission (CR) rate has been reported in newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) following imatinib-based therapy. However, the overall effect of imatinib on the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) is undetermined. Between 2002 and 2005, 100 newly diagnosed adult patients with Ph+ALL were registered to a phase II study of imatinib-combined chemotherapy (Japan Adult Leukemia Study Group Ph+ALL202 study) and 97 patients achieved CR. We compared clinical outcomes of 51 patients who received allo-HSCT in their first CR (imatinib cohort) with those of 122 historical control patients in the pre-imatinib era (pre-imatinib cohort). The probability of overall survival at 3 years after allo-HSCT was 65% (95% confidence interval (CI), 49-78%) for the imatinib cohort and 44% (95% CI, 35-52%) for the pre-imatinib cohort. Multivariate analysis confirmed that this difference was statistically significant (adjusted hazard ratio, 0.44, P=0.005). Favorable outcomes of the imatinib cohort were also observed for disease-free survival (P=0.007) and relapse (P=0.002), but not for non-relapse mortality (P=0.265). Imatinib-based therapy is a potentially useful strategy for newly diagnosed patients with Ph+ALL, not only providing them more chance to receive allo-HSCT, but also improving the outcome of allo-HSCT.

Donor-specific differences in long-term outcomes of myeloablative transplantation in adults with Philadelphia-negative acute lymphoblastic leukemia

We analyzed long-term outcomes of myeloablative stem cell transplantation (SCT) in 292 adults with Philadelphia (Ph)-negative acute lymphoblastic leukemia (ALL). Donors were related (RD; n=132), unrelated (URD; n=68; 30 well-matched (WM), 19 partially matched (PM), 19 mismatched (MM)) and autologous (AUTO; n=92). After a median follow-up of 85 months, the risk of relapse was higher for AUTO-SCT than for RD-SCT (P<0.001). MM-URD-SCT yielded higher risk of non-relapse mortality than RD-SCT (P=0.010). As a result, disease-free survival (DFS) at 5 years was inferior using AUTO (46.1%; P=0.010) or MM-URD (26.3%; P=0.036), whereas DFS from other donor sources was approximately equivalent (53.5% for RD, 63.3% for WM-URD and 57.0% for PM-URD). Other factors associated with poorer DFS included SCT beyond first complete remission (CR), older age and adverse cytogenetics. In a pairwise comparison of outcomes between RD-SCT and AUTO-SCT for patients in first CR, the inferiority of AUTO-SCT was observed, particularly in high-risk patients. Conversely, in standard-risk patients, AUTO-SCT yielded comparable outcomes to RD-SCT. SCT using RD, WM-URD or PM-URD may be considered the best donor sources for adult high-risk Ph-negative ALL.

Intensified consolidation therapy with dose-escalated doxorubicin did not improve the prognosis of adults with acute lymphoblastic leukemia: the JALSG-ALL97 study

We designed a treatment protocol for newly diagnosed adult acute lymphoblastic leukemia (ALL) in the pre-imatinib era, employing intensified consolidation therapy with a total of 330 mg/m² doxorubicin and adopting slightly modified induction and maintenance regimen of the CALGB 8811 study. Of 404 eligible patients (median age 38 years, range 15-64 years), 298 (74%) achieved complete remission (CR). The 5-year overall survival (OS) rate was 32%, and the 5-year disease-free survival (DFS) rate was 33%. Of 256 Philadelphia chromosome (Ph)-negative patients, 208 (81%) achieved CR and the 5-year OS rate was 39%, and 60 of them underwent allogeneic-hematopoietic stem cell transplantation (allo-HSCT) from related or unrelated donors during the first CR, resulting in 63% 5-year OS. Of 116 Ph-positive patients, 65 (56%) achieved CR and the 5-year OS rate was 15%, and 22 of them underwent allo-HSCT from related or unrelated donors during the first CR, resulting in 47% 5-year OS. In Ph-negative patients, multivariate analysis showed that older age, advanced performance status and unfavorable karyotypes were significant poor prognostic factors for OS and higher WBC counts for DFS. The present treatment regimen could not show a better outcome than that of our previous JALSG-ALL93 study for adult ALL.

Allogeneic hematopoietic stem cell transplantation for adult acute lymphocytic leukemia

Allogeneic hematopoietic stem cell transplantation (alloHCT) is the single most potent treatment modality to prevent relapse in adults with acute lymphocytic leukemia, but its optimal use and timing remains a matter of intense debate and research. There is general agreement that patients with clinical features of high risk for relapse should undergo alloHCT in first complete remission. However, newer studies suggest that even patients without these risk factors may benefit. Monitoring of minimal residual disease may improve risk stratification and may complement or replace conventional risk features. Prognosis in relapsed and refractory patients is dismal, and alloHCT should be performed as soon as possible. AlloHCT also offers the only reasonable chance for cure in Philadelphia chromosome-positive acute lymphocytic leukemia; the role of imatinib is not yet clearly defined. Recent developments in unrelated-donor transplantation and reduced-intensity conditioning allow the beneficial effects of alloHCT to reach a considerably wider patient population.

Treatment of Philadelphia-chromosome-positive acute lymphoblastic leukemia with imatinib in combination with chemotherapy

The presence of the Philadelphia chromosome (Ph) is associated with a very poor prognosis in acute lymphoblastic leukemia (ALL). Although hematologic complete remission (CR) is achieved in 50% to 80% of adult patients by intensive chemotherapy in multicenter studies, long-term outcome is dismal, with overall survival of approximately 10%. Currently, allogeneic hematopoietic stem cell transplantation (allo-SCT) is thought to be the only curative therapeutic modality for this leukemia in adults, but the long-term survival rates are about 40% or less, far from satisfactory. Imatinib mesylate, a recently introduced specific tyrosine kinase inhibitor of BCR-ABL, in combination with chemotherapy, resulted in more than 90% hematologic CR in adult Ph-positive ALL, including molecular CR in more than 50% of patients. The higher CR rate and less frequent relapse gave more patients a chance to receive SCT. Patients who did not qualify for allo-SCT because of the lack of a suitable donor, advanced age, or underlying medical conditions apparently showed better survival than historical control patients treated with chemotherapy alone. Although longer follow-up is required to determine the effect on survival, imatinib in combination with chemotherapy clearly has a major potential to improve the treatment of Ph-positive ALL and may cure a substantial proportion of patients without SCT.

Allogeneic stem cell transplantation for adult Philadelphia chromosome-negative acute lymphocytic leukemia: comparable survival rates but different risk factors between related and unrelated transplantation in first complete remission

To identify factors to improve the outcomes of related and unrelated allogeneic stem cell transplantations (allo-SCT) for Philadelphia chromosome-negative acute lymphocytic leukemia (Ph(-) ALL) in the first complete remission (CR1), we retrospectively analyzed 1139 Ph(-) ALL patients using the registry data, particularly the details of 641 patients transplanted in CR1. Overall survival was significantly superior among patients transplanted in CR1, but no significant difference was observed between related and unrelated allo-SCTs (related vs unrelated: 65% vs 62% at 4 years, respectively; P = .19). Among patients transplanted in CR1, relapse rates were significantly higher in related allo-SCT compared with unrelated allo-SCT, and multivariate analysis demonstrated that less than 6 months from diagnosis to allo-SCT alone was associated with relapse. On the other hand, nonrelapse mortality (NRM) was significantly higher in unrelated allo-SCT compared with related allo-SCT, and multivariate analysis demonstrated that 10 months or longer from diagnosis to allo-SCT, human leukocyte antigen mismatch, and abnormal karyotype were associated with NRM. In conclusion, our study showed comparable survival rates but different relapse rates, NRM rates, and risk factors between related and unrelated allo-SCTs. After a close consideration of these factors, the outcome of allo-SCT for adult Ph(-) ALL in CR1 could be improved.

Outcome after relapse of acute lymphoblastic leukemia in adult patients included in four consecutive risk-adapted trials by the PETHEMA Study Group

BACKGROUND

About one half of adults with acute lymphoblastic leukemia are not cured of the disease and ultimately die. The objective of this study was to explore the factors influencing the outcome of adult patients with relapsed acute lymphoblastic leukemia.

DESIGN AND METHODS

We analyzed the characteristics, the outcome and the prognostic factors for survival after first relapse in a series of 263 adult patients with acute lymphoblastic leukemia (excluding those with mature B-cell acute lymphoblastic leukemia) prospectively enrolled in four consecutive risk-adapted PETHEMA trials.

RESULTS

The median overall survival after relapse was 4.5 months (95% CI, 4-5 months) with a 5-year overall survival of 10% (95% CI, 8%-12%); 45% of patients receiving intensive second-line treatment achieved a second complete remission and 22% (95% CI, 14%-30%) of them remained disease free at 5 years. Factors predicting a good outcome after rescue therapy were age less than 30 years (2-year overall survival of 21% versus 10% for those over 30 years old; P<0.022) and a first remission lasting more than 2 years (2-year overall survival of 36% versus 17% among those with a shorter first remission; P<0.001). Patients under 30 years old whose first complete remission lasted longer than 2 years had a 5-year overall survival of 38% (95% CI, 23%-53%) and a 5-year disease-free survival of 53% (95% CI, 34%-72%).

CONCLUSIONS

The prognosis of adult patients with acute lymphoblastic leukemia who relapse is poor. Those aged less than 30 years with a first complete remission lasting longer than 2 years have reasonable possibilities of becoming long-term survivors while patients over this age or those who relapse early cannot be successfully rescued using the therapies currently available.

Adult acute lymphoblastic leukemia: concepts and strategies

Acute lymphoblastic leukemia (ALL), a clonal expansion of hematopoietic blasts, is a highly heterogeneous disease comprising many entities for which distinct treatment strategies are pursued. Although ALL is a success story in pediatric oncology, results in adults lag behind those in children. An expansion of new drugs, more reliable immunologic and molecular techniques for the assessment of minimal residual disease, and efforts at more precise risk stratification are generating new aspects of adult ALL therapy. For this review, the authors summarized pertinent and recent literature on ALL biology and therapy, and they discuss current strategies and potential implications of novel approaches to the management of adult ALL. Cancer 2010. (c) 2010 American Cancer Society.

Outcome of allogeneic bone marrow transplantation from unrelated donors for adult Philadelphia chromosome-negative acute lymphocytic leukemia in first complete-remission

The indication of allogeneic stem cell transplantation (allo-SCT) for Philadelphia chromosome-negative acute lymphocytic leukemia [Ph(-) ALL] from unrelated donors is not established. To assess its potency of unrelated patients in first complete-remission (CR1) transplanted from unrelated donors and the potential prognostic factors affecting the probability of survival, we retrospectively analyzed a total of 41 adult Ph(-) ALL patients in CR1 who underwent unrelated bone marrow transplantation at 6 transplantation centers of the Nagoya Blood and Marrow Transplantation Group between 1993 and 2006. The median age of the 41 patients was 28 years (range, 18-51 years). HLA was matched in 33 transplants, with mismatches in 8 (HLA-A allele mismatch:1, HLA-DR serological mismatch: 2, HLA-DRB1 mismatch: 5). Leukemia-free survival (LFS) at 3 and 6 years from allo-SCT was 60.3 and 47.7%, respectively. LFS at 5 years was 62.1% for those transplanted from HLA-matched donors. LFS was significantly lower with HLA-mismatched donors due to higher transplantation-related mortality. Relapse was observed in 3 patients. Our study suggested that unrelated allo-SCT could improve LFS of patients with a potential graft-versus-leukemia effect. Unrelated allo-SCT for Ph(-) ALL patients in CR1 could be more beneficial by reducing TRM, such as selecting a HLA-matched donor.

Hematopoietic stem cell transplantation for adults with acute lymphoblastic leukemia

PURPOSE OF REVIEW

The long-term survival for patients with adult acute lymphoblastic leukemia (ALL) has not significantly changed over the past two decades and, as opposed to pediatric ALL, it is less than 40% despite high initial complete remission rate. These observations raise several important issues regarding the pathobiology of adult leukemic stem cells, the ability of adults to tolerate intensive treatment and the best postremission approach.

RECENT FINDINGS

Progress has been made in understanding the biology of adult ALL and its prognostic significance. The follow-up of minimal residual disease status, adopting protocols from childhood ALL to young adults and use of targeted therapy may improve long-term survival. Transplantation for standard-risk ALL in first remission proved to be beneficial in a large cooperative group study. Limited data on the use of alternative donor transplantation as well as reduced intensity protocols are now available for consideration in specific groups of patients.

SUMMARY

Data suggest that the best antileukemic treatment should be applied in first remission and type of treatment should be based on individualized risk stratification, while incorporating recent information on alternative donors and reduced intensity approaches to transplantation.

Allogeneic hematopoietic cell transplantation (allogeneic HCT) for treatment of pediatric Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL)

BACKGROUND

Allogeneic hematopoietic cell transplant (HCT) with best available donor for children with Philadelphia positive (Ph+) acute lymphoblastic leukemia (ALL) has previously been considered standard practice. Since the introduction of imatinib into the treatment of this disease, the role of allogeneic HCT is more uncertain.

PROCEDURE

We investigated the impact of remission status, graft source, and imatinib use on transplant outcomes for 37 children with Ph+ ALL who received an allogeneic HCT at the University of Minnesota between 1990 and 2006. The median age at HCT was 7.47 (range; 1.4-16.4) years. Thirteen patients received imatinib therapy pre- and/or post-HCT (imatinib group) and 24 patients, received either no imatinib (n = 23) or only post-HCT relapse (n = 1) (non-imatinib group).

RESULTS

There was no difference in disease-free survival (DFS) or relapse between the imatinib and non-imatinib groups at 3 years (62%/15% vs. 53%/26%; P = 0.99; 0.81, respectively). There was no significant difference in transplant outcomes between matched related donor or unrelated donor (umbilical cord blood or matched unrelated marrow) recipients whereas patients receiving allogeneic HCT in first remission (CR1) had superior DFS and less relapse compared to patients transplanted in >or=CR2 (71%/16% vs. 29%/36%; P = 0.01; P = 0.05).

CONCLUSIONS

Based on this retrospective analysis at a single institution, the use of imatinib either pre- and/or post-transplant does not appear to significantly impact outcomes for children with Ph+ ALL and allogeneic HCT with the best available donor should be encouraged in CR1.

Concurrent intensive chemotherapy and imatinib before and after stem cell transplantation in newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia. Final results of the CSTIBES02 trial

BACKGROUND

Imatinib, given concurrently or alternating with chemotherapy, has improved the response and survival of patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) but relapses are still frequent. The aim of this study was to evaluate the feasibility and results of giving imatinib concurrently with intensive chemotherapy, stem cell transplantation and post-transplant imatinib maintenance therapy in patients with newly diagnosed Ph(+) ALL.

DESIGN AND METHODS

This was a phase II study of patients with newly diagnosed Ph(+) ALL given standard chemotherapy, together with imatinib (400 mg/day) until stem cell transplantation, followed by imatinib maintenance therapy for all patients regardless of the molecular status of the disease.

RESULTS

Of the 30 patients included, 27 (90%) achieved complete remission, one was resistant to treatment and two died during induction therapy. The percentages of major and complete molecular responses were 86% and 21% after induction, and 81% and 65% after consolidation, respectively. Similar results were observed assessing minimal residual disease by flow cytometry. Of the 27 patients who achieved complete remission, 21 underwent stem cell transplantation (16 allogeneic, 5 autologous). Imatinib (400 mg/day) could be administered after transplantation for a median of 3.9 months in 12 patients, although it was interrupted in 10 patients (in 2 cases because of side effects of the drug). Nine patients relapsed, four before and five after stem cell transplantation and eight patients died of transplant-related causes. With a median follow-up of 4.1 years, the probabilities (95% CI) of disease-free and overall survival were 30% (15% to 45%) and 30% (16% to 45%), respectively.

CONCLUSIONS

These results confirm that imatinib is an effective first-line treatment for adult Ph(+) ALL when given concurrently with chemotherapy, making stem cell transplantation feasible in a high proportion of patients. However, post-transplantation imatinib administration was limited, mainly because of transplantation-derived complications rather than drug-specific toxicity.

Implications of the European Organisation for Research And Treatment Of Cancer (EORTC) guidelines on the use of granulocyte colony-stimulating factor (G-CSF) for lymphoma care

Febrile neutropenia (FN) is a potentially life-threatening complication of myelosuppressive chemotherapy. The European Organisation for Research and Treatment of Cancer (EORTC) guidelines recommend use of primary granulocyte colony-stimulating factor (G-CSF) prophylaxis if the overall FN risk to a patient is >or=20%, or if a reduction in chemotherapy dose intensity correlates with a poorer outcome. Many of the regimens used for treatment of lymphoma, including R-CHOP (rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisolone), are associated with an FN risk of approximately 20% or higher. Individual patient factors that may increase the risk of FN such as advanced age or advanced disease should be taken into account when assessing the need for G-CSF support. Predictive models are being developed to facilitate individual risk assessment. Additional anti-infective prophylaxis may be indicated in some settings. There is now much evidence for the benefits of G-CSF in reducing the incidence of FN and facilitating delivery of chemotherapy, including dose-escalated and dose-dense (interval-reduced) regimens. If given according to guidelines, G-CSF has the potential to reduce FN and related morbidity. Furthermore, by facilitating delivery of planned chemotherapy, use of G-CSF may potentially influence survival in the curative setting. Implementation of the EORTC guidelines will lead to a greater proportion of patients receiving G-CSFs, but the costs involved should be at least partly offset by a reduction in FN and its associated costs, including those of hospitalization.

Favorable outcomes with alemtuzumab-conditioned unrelated donor stem cell transplantation in adults with high-risk Philadelphia chromosome-negative acute lymphoblastic leukemia in first complete remission

BACKGROUND

Approximately 40% of adults with Philadelphia chromosome-negative acute lymphoblastic leukemia achieve long-term survival following unrelated donor hematopoietic stem cell transplantation in first complete remission but severe graft-versus-host disease remains a problem affecting survival. Although T-cell depletion abrogates graft-versus-host disease, the impact on disease-free survival in acute lymphoblastic leukemia is not known.

DESIGN AND METHODS

We analyzed the outcome of 48 adults (median age 26 years) with high-risk, Philadelphia-chromosome-negative acute lymphoblastic leukemia undergoing T-cell depleted unrelated donor-hematopoietic stem cell transplantation (67% 10 of 10 loci matched) in first complete remission reported to the British Society of Blood and Marrow Transplantation Registry from 1993 to 2005.

RESULTS

T-cell depletion was carried out by in vivo alemtuzumab administration. Additional, ex vivo T-cell depletion was performed in 21% of patients. Overall survival, disease-free survival and non-relapse mortality rates at 5 years were 61% (95% CI 46-75), 59% (95% CI 45-74) and 13% (95% CI 3-25), respectively. The incidences of grades II-IV and III-IV acute graft-versus-host disease were 27% (95% CI 16-44) and 10% (95% CI 4-25), respectively. The actuarial estimate of extensive chronic graft-versus-host disease at 5 years was 22% (95%CI 13-38). High-risk cytogenetics at diagnosis was associated with a lower 5-year overall survival (47% (95% CI 27-71) vs. 68% (95% CI 44-84), p=0.045).

CONCLUSIONS

T-cell depleted hematopoietic stem cell transplantation from unrelated donors can result in good overall survival and low non-relapse mortality for adults with high-risk acute lymphoblastic leukemia in first complete remission and merits prospective evaluation.

Heritable T-cell malignancy models established in a zebrafish phenotypic screen

T cell neoplasias are common in pediatric oncology, and include acute lymphoblastic leukemia (T-ALL) and lymphoblastic lymphoma (T-LBL). These cancers have worse prognoses than their B cell counterparts, and their treatments carry significant morbidity. While many pediatric malignancies have characteristic translocations, most T lymphocyte-derived diseases lack cytogenetic hallmarks. Lacking these informative lesions, insight into their molecular pathogenesis is less complete. Although dysregulation of the NOTCH1 pathway occurs in a substantial fraction of cases, many other genetic lesions of T cell malignancy have not yet been determined. To address this deficiency, we pioneered a phenotype-driven forward-genetic screen in zebrafish (Danio rerio). Using transgenic fish with T lymphocyte-specific expression of enhanced green fluorescent protein (EGFP), we performed chemical mutagenesis, screened animals for GFP⁺ tumors, and identified multiple lines with a heritable predisposition to T cell malignancy. In each line, patterns of infiltration and morphologic appearance resembled human T-ALL and T-LBL. T cell receptor analyses confirmed their clonality. Malignancies were transplantable and contained leukemia-initiating cells (LIC), like their human correlates. In summary, we have identified multiple zebrafish mutants that recapitulate human T cell neoplasia and show heritable transmission. These vertebrate models provide new genetic platforms for the study of these important human cancers.

Chemotherapy of acute leukemia in adults

BACKGROUND

General therapeutic options for adult patients with acute leukemia are reviewed and specific new treatment strategies are described.

OBJECTIVE

Treatment results and controversial issues on current and future antileukemic strategies are discussed.

METHODS

Data in this review came from the published literature.

RESULTS/CONCLUSION

In the past years, striking new developments have been noticeable in the treatment of adult acute leukemia. However, the overall outcome of adult acute leukemia remains poor, particularly in older patients. Intensive chemotherapy remains the standard for leukemia treatment but several approaches using new cytotoxic agents seem promising. Therapeutic targeting of specific biologic abnormalities present in the leukemia cell population might, in a near future, improve outcome of adult leukemia patients.

Level of DNA topoisomerase IIalpha mRNA predicts the treatment response of relapsed acute leukemic patients

The DNA topoisomerase IIalpha (Topo IIalpha) is known as a target enzyme for many chemotherapeutic agents. We investigated the Topo IIalpha mRNA expression by real-time RT-PCR in 37 paired samples at diagnosis and at relapse of acute leukemic patients in relation to drug sensitivity and clinical outcome. The Topo IIalpha levels in leukemic blasts at relapse were significantly higher than that at diagnosis, especially in ALL. The increase in the Topo IIalpha level at relapse was significant in cases which could not achieve a second remission, but not significant in cases which achieved a second remission. These results suggest that the change of Topo IIalpha expression in leukemic blasts at relapse may predict therapeutic responsiveness.

Recent advances in the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia

The advent of imatinib, a selective inhibitor of the ABL tyrosine kinase, has revolutionized the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Combined with chemotherapy, imatinib exerts remarkable efficacy in patients with newly diagnosed disease with a complete remission (CR) rate of 95% and a survival rate of 55% at 3 years. Profound eradication of leukemia cells not only provides patients with a better chance for receiving allogeneic hematopoietic stem cell transplantation during first CR but also contributes to durable CR even without transplantation. Despite such improvement, however, relapse does occur, mainly owing to acquisition of resistance. Growing comprehension of the molecular mechanisms of resistance to imatinib has led to the development of novel BCR-ABL inhibitors that yield higher affinity for BCR-ABL and/or potent inhibitory activity against other target molecules such as SRC family kinases. The second-generation ABL kinase inhibitors, namely dasatinib and nilotinib, are already showing clinical activity in patients with imatinib-resistant Ph+ ALL, and other novel agents are undergoing preclinical and early clinical evaluation. Further improvement in treatment results will be achieved by identifying each patient's disease profile based on information obtained before and during treatment and by optimizing subsequent treatment accordingly.