PHF6-altered T-ALL Harbor Epigenetic Repressive Switch at Bivalent Promoters and Respond to 5-Azacitidine and Venetoclax

PURPOSE

To assess the impact of PHF6 alterations on clinical outcome and therapeutical actionability in T-cell acute lymphoblastic leukemia (T-ALL).

EXPERIMENTAL DESIGN

We described PHF6 alterations in an adult cohort of T-ALL from the French trial Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003/2005 and retrospectively analyzed clinical outcomes between PHF6-altered (PHF6ALT) and wild-type patients. We also used EPIC and chromatin immunoprecipitation sequencing data of patient samples to analyze the epigenetic landscape of PHF6ALT T-ALLs. We consecutively evaluated 5-azacitidine efficacy, alone or combined with venetoclax, in PHF6ALT T-ALL.

RESULTS

We show that PHF6 alterations account for 47% of cases in our cohort and demonstrate that PHF6ALT T-ALL presented significantly better clinical outcomes. Integrative analysis of DNA methylation and histone marks shows that PHF6ALT are characterized by DNA hypermethylation and H3K27me3 loss at promoters physiologically bivalent in thymocytes. Using patient-derived xenografts, we show that PHF6ALT T-ALL respond to the 5-azacytidine alone. Finally, synergism with the BCL2-inhibitor venetoclax was demonstrated in refractory/relapsing (R/R) PHF6ALT T-ALL using fresh samples. Importantly, we report three cases of R/R PHF6ALT patients who were successfully treated with this combination.

CONCLUSIONS

Overall, our study supports the use of PHF6 alterations as a biomarker of sensitivity to 5-azacytidine and venetoclax combination in R/R T-ALL.

Genetic alterations and MRD refine risk assessment for KMT2A-rearranged B-cell precursor ALL in adults: a GRAALL study

KMT2A-rearranged (KMT2A-r) B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is widely recognized as a high-risk leukemia in both children and adults. However, there is a paucity of data on adults treated in recent protocols, and the optimal treatment strategy for these patients is still a matter of debate. In this study, we set out to refine the prognosis of adult KMT2A-r BCP-ALL treated with modern chemotherapy regimen and investigate the prognostic impact of comutations and minimal residual disease (MRD). Of 1091 adult patients with Philadelphia-negative BCP-ALL enrolled in 3 consecutive trials from the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL), 141 (12.9%) had KMT2A-r, with 5-year cumulative incidence of relapse (CIR) and overall survival (OS) rates of 40.7% and 53.3%, respectively. Molecular profiling highlighted a low mutational burden in this subtype, reminiscent of infant BCP-ALL. However, the presence of TP53 and/or IKZF1 alterations defined a subset of patients with significantly poorer CIR (69.3% vs 36.2%; P = .001) and OS (28.1% vs 60.7%; P = .006) rates. Next, we analyzed the prognostic implication of MRD measured after induction and first consolidation, using both immunoglobulin (IG) or T-cell receptor (TR) gene rearrangements and KMT2A genomic fusion as markers. In approximately one-third of patients, IG/TR rearrangements were absent or displayed clonal evolution during the disease course, compromising MRD monitoring. In contrast, KMT2A-based MRD was highly reliable and strongly associated with outcome, with early good responders having an excellent outcome (3-year CIR, 7.1%; OS, 92.9%). Altogether, our study reveals striking heterogeneity in outcomes within adults with KMT2A-r BCP-ALL and provides new biomarkers to guide risk-based therapeutic stratification.

Adult Low-Hypodiploid Acute Lymphoblastic Leukemia Emerges from Preleukemic TP53-Mutant Clonal Hematopoiesis

Low hypodiploidy defines a rare subtype of B-cell acute lymphoblastic leukemia (B-ALL) with a dismal outcome. To investigate the genomic basis of low-hypodiploid ALL (LH-ALL) in adults, we analyzed copy-number aberrations, loss of heterozygosity, mutations, and cytogenetics data in a prospective cohort of Philadelphia (Ph)-negative B-ALL patients (n = 591, ages 18-84 years), allowing us to identify 80 LH-ALL cases (14%). Genomic analysis was critical for evidencing low hypodiploidy in many cases missed by cytogenetics. The proportion of LH-ALL within Ph-negative B-ALL dramatically increased with age, from 3% in the youngest patients (under 40 years old) to 32% in the oldest (over 55 years old). Somatic TP53 biallelic inactivation was the hallmark of adult LH-ALL, present in virtually all cases (98%). Strikingly, we detected TP53 mutations in posttreatment remission samples in 34% of patients. Single-cell proteogenomics of diagnosis and remission bone marrow samples evidenced a preleukemic, multilineage, TP53-mutant clone, reminiscent of age-related clonal hematopoiesis.

SIGNIFICANCE

We show that low-hypodiploid ALL is a frequent entity within B-ALL in older adults, relying on somatic TP53 biallelic alteration. Our study unveils a link between aging and low-hypodiploid ALL, with TP53-mutant clonal hematopoiesis representing a preleukemic reservoir that can give rise to aneuploidy and B-ALL. See related commentary by Saiki and Ogawa, p. 102. This article is highlighted in the In This Issue feature, p. 101.

PRC2 loss of function confers a targetable vulnerability to BET proteins in T-ALL

T-cell acute lymphoblastic leukemia (T-ALL) is a group of aggressive hematological cancers with dismal outcomes that are in need of new therapeutic options. Polycomb repressor complex 2 (PRC2) loss-of-function alterations were reported in pediatric T-ALL, yet their clinical relevance and functional consequences remain elusive. Here, we extensively analyzed PRC2 alterations in a large series of 218 adult T-ALL patients. We found that PRC2 genetic lesions are frequent events in T-ALL and are not restricted to early thymic precursor ALL. PRC2 loss of function associates with activating mutations of the IL7R/JAK/STAT pathway. PRC2-altered T-ALL patients respond poorly to prednisone and have low bone marrow blast clearance and persistent minimal residual disease. Furthermore, we identified that PRC2 loss of function profoundly reshapes the genetic and epigenetic landscapes, leading to the reactivation of stem cell programs that cooperate with bromodomain and extraterminal (BET) proteins to sustain T-ALL. This study identifies BET proteins as key mediators of the PRC2 loss of function-induced remodeling. Our data have uncovered a targetable vulnerability to BET inhibition that can be exploited to treat PRC2-altered T-ALL patients.

DNMT3A mutation is associated with increased age and adverse outcome in adult T-cell acute lymphoblastic leukemia

The prognostic implications of DNMT3A genotype in T-cell acute lymphoblastic leukemia are incompletely understood. We performed comprehensive genetic and clinico-biological analyses of T-cell acute lymphoblastic leukemia patients with DNMT3A mutations treated during the GRAALL-2003 and -2005 studies. Eighteen of 198 cases (9.1%) had DNMT3A alterations. Two patients also had DNMT3A mutations in non-leukemic cell DNA, providing the first potential evidence of age-related clonal hematopoiesis in T-cell acute lymphoblastic leukemia. DNMT3A mutation was associated with older age (median 43.9 years vs. 29.4 years, P<0.001), immature T-cell receptor genotype (53.3% vs. 24.4%, P=0.016) and lower remission rates (72.2% mutated vs. 94.4% non-mutated, P=0.006). DNMT3A alterations were significantly associated with worse clinical outcome, with higher cumulative incidence of relapse (HR 2.33, 95% CI: 1.05-5.16, P=0.037) and markedly poorer event-free survival (HR 3.22, 95% CI: 1.81-5.72, P<0.001) and overall survival (HR 2.91, 95% CI: 1.56-5.43, P=0.001). Adjusting for age as a covariate, or restricting the analysis to patients over 40 years, who account for almost 90% of DNMT3A-mutated cases, did not modify these observations. In multivariate analysis using the risk factors that were used to stratify treatment during the GRAALL studies, DNMT3A mutation was significantly associated with shorter event-free survival (HR 2.33, 95% CI: 1.06 – 4.04, P=0.02). Altogether, these results identify DNMT3A genotype as a predictor of aggressive T-cell acute lymphoblastic leukemia biology. The GRAALL-2003 and -2005 studies were registered at http://www.ClinicalTrials.gov as #NCT00222027 and #NCT00327678, respectively.

Intensified Therapy of Acute Lymphoblastic Leukemia in Adults: Report of the Randomized GRAALL-2005 Clinical Trial

Purpose

To evaluate randomly the role of hyperfractionated cyclophosphamide (hyper-C) dose intensification in adults with newly diagnosed Philadelphia chromosome–negative acute lymphoblastic leukemia treated with a pediatric-inspired protocol and to determine the upper age limit for treatment tolerability in this context.

Patients and Methods

A total of 787 evaluable patients (B/T lineage, 525 and 262, respectively; median age, 36.1 years) were randomly assigned to receive a standard dose of cyclophosphamide or hyper-C during first induction and late intensification. Compliance with chemotherapy was assessed by median doses actually received during each treatment phase by patients potentially exposed to the full planned doses.

Results

Overall complete remission (CR) rate was 91.9%. With a median follow-up of 5.2 years, the 5-year rate of event-free survival (EFS) and overall survival (OS) was 52.2% (95% CI, 48.5% to 55.7%) and 58.5% (95% CI, 54.8% to 61.9%), respectively. Randomization to the hyper-C arm did not increase the CR rate or prolong EFS or OS. As a result of worse treatment tolerance, advanced age continuously affected CR rate, EFS, and OS, with 55 years as the best age cutoff. At 5 years, EFS was 55.7% (95% CI, 51.8% to 59.4%) for patients younger than 55 years of age versus 25.8% (95% CI, 19.9% to 35.6%) in older patients (hazard ratio, 2.16; P < .001). Patients ≥ 55 years of age, in whom a lower compliance to the whole planned chemotherapy was observed, benefited significantly from hyper-C, whereas younger patients did not.

Conclusion

No significant benefit was associated with the introduction of a hyper-C sequence into a frontline pediatric-like adult acute lymphoblastic leukemia therapy. Overall, tolerability of an intensive pediatric-derived treatment was poor in patients ≥ 55 years of age.

Rituximab in B-Lineage Adult Acute Lymphoblastic Leukemia

BACKGROUND

Treatment with rituximab has improved the outcome for patients with non-Hodgkin's lymphoma. Patients with B-lineage acute lymphoblastic leukemia (ALL) may also have the CD20 antigen, which is targeted by rituximab. Although single-group studies suggest that adding rituximab to chemotherapy could improve the outcome in such patients, this hypothesis has not been tested in a randomized trial.

METHODS

We randomly assigned adults (18 to 59 years of age) with CD20-positive, Philadelphia chromosome (Ph)-negative ALL to receive chemotherapy with or without rituximab, with event-free survival as the primary end point. Rituximab was given during all treatment phases, for a total of 16 to 18 infusions.

RESULTS

From May 2006 through April 2014, a total of 209 patients were enrolled: 105 in the rituximab group and 104 in the control group. After a median follow-up of 30 months, event-free survival was longer in the rituximab group than in the control group (hazard ratio, 0.66; 95% confidence interval [CI], 0.45 to 0.98; P=0.04); the estimated 2-year event-free survival rates were 65% (95% CI, 56 to 75) and 52% (95% CI, 43 to 63), respectively. Treatment with rituximab remained associated with longer event-free survival in a multivariate analysis. The overall incidence rate of severe adverse events did not differ significantly between the two groups, but fewer allergic reactions to asparaginase were observed in the rituximab group.

CONCLUSIONS

Adding rituximab to the ALL chemotherapy protocol improved the outcome for younger adults with CD20-positive, Ph-negative ALL. (Funded by the Regional Clinical Research Office, Paris, and others; ClinicalTrials.gov number, NCT00327678 .).

Cerebral venous thrombosis in adult patients with acute lymphoblastic leukemia or lymphoblastic lymphoma during induction chemotherapy with l-asparaginase: The GRAALL experience

Central nervous system (CNS) thrombotic events are a well-known complication of acute lymphoblastic leukemia (ALL) induction therapy, especially with treatments including l-asparaginase (l-ASP). Data on risk factors and clinical evolution is still lacking in adult patients. We report on the clinical evolution of 22 CNS venous thrombosis cases occurring in 708 adults treated for ALL or lymphoblastic lymphoma (LL) with the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-induction protocol, which included eight L-ASP (6,000 IU/m(2) ) infusions. The prevalence of CNS thrombosis was 3.1%. CNS thrombosis occurred after a median of 18 days (range: 11-31) when patients had received a median of three l-ASP injections (range: 2-7). Patients with CNS thrombosis exhibited a median antithrombin (AT) nadir of 47.5% (range: 36-67%) at Day 17 (range: D3-D28), and 95% of them exhibited AT levels lower than 60%. There were no evident increase in hereditary thrombotic risk factors prevalence, and thrombosis occurred despite heparin prophylaxis which was performed in 90% of patients. Acquired AT deficiency was frequently detected in patients with l-ASP-based therapy, and patients with CNS thrombosis received AT prophylaxis (45%) less frequently than patients without CNS thrombosis (83%), P = 0.0002). CNS thrombosis was lethal in 5% of patients, while 20% had persistent sequelae. One patient received all planned l-ASP infusions without recurrence of CNS thrombotic whereas l-ASP injections were discontinued in 20 patients during the management of thrombosis without a significant impact on overall survival (P = 0.4).

Toward a NOTCH1/FBXW7/RAS/PTEN-based oncogenetic risk classification of adult T-cell acute lymphoblastic leukemia: a Group for Research in Adult Acute Lymphoblastic Leukemia study

PURPOSE

The Group for Research in Adult Acute Lymphoblastic Leukemia (GRAALL) recently reported a significantly better outcome in T-cell acute lymphoblastic leukemia (T-ALL) harboring NOTCH1 and/or FBXW7 (N/F) mutations compared with unmutated T-ALL. Despite this, one third of patients with N/F-mutated T-ALL experienced relapse.

PATIENTS AND METHODS

In a series of 212 adult T-ALLs included in the multicenter randomized GRAALL-2003 and -2005 trials, we searched for additional N/K-RAS mutations and PTEN defects (mutations and gene deletion).

RESULTS

N/F mutations were identified in 143 (67%) of 212 patients, and lack of N/F mutation was confirmed to be associated with a poor prognosis. K-RAS, N-RAS, and PTEN mutations/deletions were identified in three (1.6%) of 191, 17 (8.9%) of 191, and 21 (12%) of 175 patients, respectively. The favorable prognostic significance of N/F mutations was restricted to patients without RAS/PTEN abnormalities. These observations led us to propose a new T-ALL oncogenetic classifier defining low-risk patients as those with N/F mutation but no RAS/PTEN mutation (97 of 189 patients; 51%) and all other patients (49%; including 13% with N/F and RAS/PTEN mutations) as high-risk patients. In multivariable analysis, this oncogenetic classifier remained the only significant prognostic covariate (event-free survival: hazard ratio [HR], 3.2; 95% CI, 1.9 to 5.15; P < .001; and overall survival: HR, 3.2; 95% CI, 1.9 to 5.6; P < .001).

CONCLUSION

These data demonstrate that the presence of N/F mutations in the absence of RAS or PTEN abnormalities predicts good outcome in almost 50% of adult T-ALL. Conversely, the absence of N/F or presence of RAS/PTEN alterations identifies the remaining cohort of patients with poor prognosis.

Philadelphia Chromosome-positive Acute Lymphoblastic Leukemia in the Elderly: Prognostic Factors and Treatment Outcome

Data on all patients diagnosed with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) aged 55 or older, seen in our institution over a 17-year period, were studied to determine the incidence and range of clinical and biological subtypes, and the outcome of different therapeutic approaches. Twenty-five Ph+ ALL cases (median age: 64 years) were diagnosed between 1986 and 2003 (28% of all B-lineage elderly ALL seen during this period). Karyotypic analysis was performed successfully in 22 cases, while 3 were only diagnosed by molecular biology analysis. All patients had B-cell lineage ALL. Co-expression of myeloid markers was observed in 20% of tested cases. One patient died before chemotherapy could be given. All other patients received "curative" treatment according to different protocols used during the period of study. Overall the complete remission (CR) rate was 76% (95% confidence interval, CI: 55-91%). Fifteen patients achieved CR after one course of chemotherapy and 4 patients after salvage therapy. Median disease-free survival (DFS) of the entire cohort was 5.6 months (95% CI: 4.5-8.4 months) and median overall survival was 10.1 months (95% CI: 7.9-13 months). In multivariate analysis, age>or=70 years was of poor prognostic value for achieving CR (p=0.05) and hyperleukocytosis at diagnosis was of poor prognostic value for overall survival (p=0.001). Overall survival duration was not significantly influenced by achieving CR. Ph+ ALL patients did not show a significant difference in terms of outcome as compared with Philadelphia-negative ALL patients. The very poor overall outcome in elderly patients with Ph+ ALL may be significantly improved by the introduction of imatinib mesylate into current treatment regimens.

PAX5 mutations occur frequently in adult B-cell progenitor acute lymphoblastic leukemia and PAX5 haploinsufficiency is associated with BCR-ABL1 and TCF3-PBX1 fusion genes: a GRAALL study

Adult and child B-cell progenitor acute lymphoblastic leukemia (BCP-ALL) differ in terms of incidence and prognosis. These disparities are mainly due to the molecular abnormalities associated with these two clinical entities. A genome-wide analysis using oligo SNP arrays recently demonstrated that PAX5 (paired-box domain 5) is the main target of somatic mutations in childhood BCP-ALL being altered in 38.9% of the cases. We report here the most extensive analysis of alterations of PAX5 coding sequence in 117 adult BCP-ALL patients in the unique clinical protocol GRAALL-2003/GRAAPH-2003. Our study demonstrates that PAX5 is mutated in 34% of adult BCP-ALL, mutations being partial or complete deletion, partial or complete amplification, point mutation or fusion gene. PAX5 alterations are heterogeneous consisting in complete loss in 17%, focal deletions in 10%, point mutations in 7% and translocations in 1% of the cases. PAX5 complete loss and PAX5 point mutations differ. PAX5 complete loss seems to be a secondary event and is significantly associated with BCR-ABL1 or TCF3-PBX1 fusion genes and a lower white blood cell count.

Pediatric-Inspired Therapy in Adults With Philadelphia Chromosome–Negative Acute Lymphoblastic Leukemia: The GRAALL-2003 Study

Purpose

Retrospective comparisons have suggested that adolescents or teenagers with acute lymphoblastic leukemia (ALL) benefit from pediatric rather than adult chemotherapy regimens. Thus, the aim of the present phase II study was to test a pediatric-inspired treatment, including intensified doses of nonmyelotoxic drugs, such as prednisone, vincristine, or l-asparaginase, in adult patients with ALL up to the age of 60 years.

Patients and Methods

Between 2003 and 2005, 225 adult patients (median age, 31 years; range, 15 to 60 years) with Philadelphia chromosome–negative ALL were enrolled onto the Group for Research on Adult Acute Lymphoblastic Leukemia 2003 protocol, which included several pediatric options. Some adult options, such as allogeneic stem-cell transplantation for patients with high-risk ALL, were nevertheless retained. Results were retrospectively compared with the historical France-Belgium Group for Lymphoblastic Acute Leukemia in Adults 94 (LALA-94) trial experience in 712 patients age 15 to 55 years.

Results

Complete remission rate was 93.5%. At 42 months, event-free survival (EFS) and overall survival (OS) rates were 55% (95% CI, 48% to 52%) and 60% (95% CI, 53% to 66%), respectively. Age remained an important bad prognostic factor, with 45 years of age as best cutoff. In older versus younger patients, there was a higher cumulative incidence of chemotherapy-related deaths (23% v 5%, respectively; P < .001) and deaths in first CR (22% v 5%, respectively; P < .001), whereas the incidence of relapse remained stable (30% v 32%, respectively). Complete remission rate (P = .02), EFS (P < .001), and OS (P < .001) compared favorably with the previous LALA-94 experience.

Conclusion

These results suggest that pediatric-inspired therapy markedly improves the outcome of adult patients with ALL, at least until the age of 45 years.

Central nervous system involvement in adult acute lymphoblastic leukemia at diagnosis and/or at first relapse: results from the GET-LALA group

Outcome of adult acute lymphoblastic leukemia (ALL) with central nervous system (CNS) involvement is not clearly defined. We studied 104 patients presenting with CNS involvement at diagnosis among 1493 patients (7%) included into the LALA trials, and 109 patients presenting CNS disease at the time of first relapse among the 709 relapsing patients (15%). Eighty-seven patients (84%) with CNS leukemia at diagnosis achieved complete remission (CR). Fifty-three patients underwent stem cell transplantation (SCT): 25 allogeneic SCT, 28 autologous SCT, while 34 continued with chemotherapy alone. Seven-year overall survival (OS) and disease-free survival (DFS) were 34% and 35%, respectively. There were no significant differences in terms of CR, OS and DFS among patients with CNS involvement at diagnosis and those without CNS disease. There were also no differences among the two groups regarding T lineage ALL, B lineage ALL, and among those who underwent SCT. After a first relapse, 38 patients with CNS recurrence (35%) achieved a second CR. The median OS was 6.3 months. Outcome was similar to that of relapsing patients without CNS disease. CNS leukemia in adult ALL is uncommon at diagnosis as well as at the time of first relapse. With intensification therapy, patients with CNS leukemia at diagnosis have a similar outcome than those who did not present with CNS involvement. CNS leukemia at first relapse remains of similar poor prognosis than all other adult ALL in first relapse.

Outcome of treatment after first relapse in adults with acute lymphoblastic leukemia initially treated by the LALA-94 trial

Fifty-four percent of adults with acute lymphoblastic leukemia (ALL) who entered the LALA-94 trial experienced a first relapse. We examined the outcome of these 421 adult patients. One hundred and eighty-seven patients (44%) achieved a second complete remission (CR). The median disease-free survival (DFS) was 5.2 months with a 5-year DFS at 12%. Factors predicting a better outcome after relapse were any transplant performed in second CR (P<0.0001), a first CR duration >1 year (P=0.04) and platelet level >100 x 10(9)/l at relapse (P=0.04). Risk groups defined at diagnosis and treatment received in first CR did not influence the outcome after relapse. The best results were obtained in a subset of patients who were eligible for allogeneic stem cell transplantation (SCT). Geno-identical allogeneic SCT was performed in 55 patients, and 3 patients received donor lymphocyte infusions. Forty-four transplantations were performed from an unrelated donor (of which four were cord blood). We conclude that most adult patients with recurring ALL could not be rescued using current available therapies, although allogeneic SCT remains the best therapeutic option.

Proportion of long-term event-free survivors and lifetime of adult patients not cured after a standard acute lymphoblastic leukemia therapeutic program

BACKGROUND

In adult acute lymphoblastic leukemia, treatment results generally are expressed in terms of overall survival or disease-free survival at 3 years. In this investigation, the authors attempted to express the results in terms of the proportion of long-term disease-free survivors and in terms of lifetime in patients who developed recurrent disease or died.

METHODS

Univariate and multivariate analyses were used to assess the influence of different covariates on the 2 result criteria in 922 participants in the Adult Acute Lymphoblastic Leukemia-94 multicenter trial.

RESULTS

The proportion of long-term survivors was 21.5% (95% confidence interval [95% CI], 18.1-25.4%) and was higher in women than in men. The proportion decreased with increasing age, white blood cell count, and lactate dehydrogenase level. The lowest proportion was observed in patients ages 44 years to 55 years (11.4%; 95% CI, 7-17.9%) and in patients with the t(9;22) BCR-ABL karyotype (13.4%; 95% CI, 8.8-19.8%), and the highest proportion was observed in patients with the t(4;11) MLL-AF4 karyotype (31.3%; 95% CI, 18.2-48.3%). The mean expected lifetime of patients who were not cured was 11.4 months (95% CI, 9.1-14.1 months). It was longer in men than in women and was shorter with increasing age, performance status, hemoglobin level, and white blood cell count.

CONCLUSIONS

The results of this study highlighted and specified the importance of some classic prognostic factors in patients with acute lymphoblastic leukemia.

Imatinib combined with induction or consolidation chemotherapy in patients with de novo Philadelphia chromosome-positive acute lymphoblastic leukemia: results of the GRAAPH-2003 study

The combination of imatinib with chemotherapy has been recently reported as very promising in patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). During 2004 and 2005, 45 patients with newly diagnosed Ph+ ALL were treated in the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAAPH) 2003 study, in which imatinib was started with HAM (mitoxantrone with intermediate-dose cytarabine) consolidation in good early responders (corticosensitive and chemosensitive ALL) or earlier during the induction course in combination with dexamethasone and vincristine in poor early responders (corticoresistant and/or chemoresistant ALL). Imatinib was then continuously administered until stem cell transplantation (SCT). Overall, complete remission (CR) and BCR-ABL real-time quantitative polymerase chain reaction (RQ-PCR) negativity rates were 96% and 29%, respectively. All of the 22 CR patients (100%) with a donor actually received allogeneic SCT in first CR. At 18 months, the estimated cumulative incidence of relapse, disease-free survival, and overall survival were 30%, 51%, and 65%, respectively. These 3 end points compared very favorably with results obtained in the pre-imatinib LALA-94 trial. This study confirms the value of the combined approach and encourages prospective trials to define the optimal chemotherapy that has to be combined with imatinib and to carefully reevaluate the place of allogeneic SCT in this new context.

Initial and late prognostic factors to predict survival in adult acute lymphoblastic leukaemia

Factors able to predict overall survival in adult patients with acute lymphoblastic leukaemia were assessed according to the period since initiation of the treatment using a Cox proportional hazards model. This period covers successively an initial period during the induction treatment and a consolidation period during the postinduction treatment. From 1994 to 2002, 922 patients with acute lymphoblastic leukaemia (excluding French-American-British L3 subtype) were enrolled in a multicentre protocol and followed, with a mean follow up of 58 months. A multivariate time-segmented analysis was performed on 658 patients. Analyses of the initial (before 100 d) and the late phases were realised after stratification on the type of induction treatment and on the different treatment strategies respectively. Age was the sole factor that influenced survival during the initial phase (hazard ratio 1.48 per 10-yr increase; P < 0.01). Factors that predicted survival during the late phase were age (hazard ratio 1.12, P = 0.02), white blood cells count (hazard ratio 1.01 per 10(10) cells/L increase; P < 0.05), lactic dehydrogenase level (hazard ratio 1.001 for 10 IU/L increase; P < 0.01) and t(9;22) karyotype or miscellaneous others vs. normal karyotype (hazard ratios 1.40; P < 0.01 and 1.06; P = 0.04 respectively). This analysis suggests that predictive factors may be split into tolerance factors and haematological factors. Determination of such factors is crucial to adapt postremission therapeutic strategies in acute lymphoblastic leukaemia.

Imatinib and methylprednisolone alternated with chemotherapy improve the outcome of elderly patients with Philadelphia-positive acute lymphoblastic leukemia: results of the GRAALL AFR09 study

Acute lymphoblastic leukemia (ALL) in the elderly is characterized by its ominous prognosis. On the other hand, imatinib has demonstrated remarkable, although transient, activity in relapsed and refractory Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL), which prompted us to assess the use of imatinib in previously untreated elderly patients. ALL patients aged 55 years or older were given steroids during 1 week. Ph+ve cases were then offered a chemotherapy-based induction followed by a consolidation phase with imatinib and steroids during 2 months. Patients in complete response (CR) after consolidation were given 10 maintenance blocks of alternating chemotherapy, including two additional 2-month blocks of imatinib. Thirty patients were included in this study and are compared with 21 historical controls. Out of 29 assessable patients, 21 (72%, confidence interval (CI): 53-87%) were in CR after induction chemotherapy vs 6/21 (29%, CI: 11-52%) in controls (P=0.003). Five additional CRs were obtained after salvage with imatinib and four after salvage with additional chemotherapy in the control group. Overall survival (OS) is 66% at 1 year vs 43% in the control group (P=0.005). The 1-year relapse-free survival is 58 vs 11% (P=0.0003). The use of imatinib in elderly patients with Ph+ ALL is very likely to improve outcome, including OS.

Autologous stem cell transplantation in adults with acute lymphoblastic leukemia in first complete remission: analysis of the LALA-85, -87 and -94 trials

To evaluate the results of autologous stem cell transplantation (ASCT) in a large population of adults with acute lymphoblastic leukemia (ALL) in first complete remission (CR), we performed an individual data-based overview of the last three trials from the LALA group. Overall, 349 patients with ALL prospectively randomized in the consecutive LALA-85, -87, and -94 trials to receive either ASCT or chemotherapy as post-CR treatment were analyzed. Eligibility criteria were 15-50-year-old patients without sibling donors in both LALA-85/87 trials and 15-55-year-old patients with high-risk ALL and no sibling donors in the LALA-94 trial. Intent-to-treat analysis, which compared 175 patients from the ASCT arm to 174 patients from the chemotherapy arm, showed that ASCT was associated with a lower cumulative incidence of relapse (66 vs 78% at 10 years; P=0.05), without significant gain in disease-free or overall survival. Despite a possible lack of statistical power, a nested case-control analysis performed in 85 patient pairs adjusted for time to transplant and prognostic covariates confirmed these intent-to-treat results in patients actually transplanted. Of interest, the reduced relapse risk after ASCT translated in better disease-free survival in the 300 rapid responders who reached CR after the first induction course.

The activity of French research ethics committees and characteristics of biomedical research protocols involving humans: a retrospective cohort study

BACKGROUND

Clinical trials throughout the world must be evaluated by research ethics committees. No one has yet attempted to clearly quantify at the national level the activity of ethics committees and describe the characteristics of the protocols submitted. The objectives of this study were to describe 1) the workload and the activity of Research Ethics Committees in France, and 2) the characteristics of protocols approved on a nation-wide basis.

METHODS

Retrospective cohort of 976 protocols approved by a representative sample of 25/48 of French Research Ethics Committees in 1994. Protocols characteristics (design, study size, investigator), number of revisions requested by the ethics committee before approval, time to approval and number of amendments after approval were collected for each protocol by trained research assistant using the committee's files and archives.

RESULTS

Thirty-one percent of protocols were approved with no modifications requested in 16 days (95% CI: 14-17). The number of revisions requested by the committee, and amendments submitted by the investigator was on average respectively 39 (95% CI: 25-53) and 37 (95% CI: 27-46), per committee and per year. When revisions were requested, the main reasons were related to information to the patient (28%) and consent modalities (18%). Drugs were the object of research in 68% of the protocols examined. The majority of the research was national (80%) with a predominance of single-centre studies. Workload per protocol has been estimated at twelve and half hours on average for administrative support and at eleven and half hours for expertise.

CONCLUSION

The estimated workload justifies specific and independent administrative and financial support for Research Ethics Committees.

Fate of biomedical research protocols and publication bias in France: retrospective cohort study

OBJECTIVES

To describe the fate of protocols approved by the French research ethics committees, a national system created by the French 1988 Huriet-Sérusclat Act; to assess publication bias at a national level.

DESIGN

Retrospective cohort study.

SETTING

Representative sample of 25/48 French research ethics committees in 1994. PROTOCOLS: 649 research protocols approved by committees, with follow-up information.

MAIN OUTCOME MEASURES

Protocols' initial characteristics (design, study size, investigator) abstracted from committees' archives; follow-up information (rates of initiation, completion, and publication) obtained from mailed questionnaire to principal investigators.

RESULTS

Completed questionnaires were available for 649/976 (69%) protocols. Of these, 581 (90%) studies were initiated, 501/581 (86%) were completed, and 190/501 (38%) were published. Studies with confirmatory results were more likely to be published as scientific papers than were studies with inconclusive results (adjusted odds ratio 4.59, 95% confidence interval 2.21 to 9.54). Moreover, studies with confirmatory results were published more quickly than studies with inconclusive results (hazard ratio 2.48, 1.36 to 4.55).

CONCLUSION

At a national level, too many research studies are not completed, and among those completed too many are not published. We suggest capitalising on research ethics committees to register and follow all authorised research on human participants on a systematic and prospective basis.

Outcome of treatment in adults with acute lymphoblastic leukemia: analysis of the LALA-94 trial

PURPOSE

We analyzed the benefits of a risk-adapted postremission strategy in adult lymphoblastic leukemia (ALL), and re-evaluated stem-cell transplantation (SCT) for high-risk ALL.

PATIENTS AND METHODS

A total of 922 adult patients entered onto the trial according to risk groups: standard-risk ALL (group 1), high-risk ALL (group 2), Philadelphia chromosome-positive ALL (group 3), and CNS-positive ALL (group 4). All received a standard four-drug/4-week induction course. Patients from group 1 who achieved a complete remission (CR) after one course of induction therapy were randomly assigned between intensive and less intensive postremission chemotherapy, whereas those who achieved CR after salvage therapy were then included in group 2. Patients in groups 2, 3, and 4 with an HLA-identical sibling were assigned to allogeneic SCT. In groups 3 and 4, autologous SCT was offered to all other patients, whereas in group 2 they were randomly assigned between chemotherapy and autologous SCT.

RESULTS

Overall, 771 patients achieved CR (84%). Median disease-free survival (DFS) was 17.5 months, with 3-year DFS at 37%. In group 1, the 3-year DFS rate was 41%, with no difference between arms of postremission randomization. In groups 2 and 4, the 3-year DFS rates were 38% and 44%, respectively. In group 2, autologous SCT and chemotherapy resulted in comparable median DFS. Patients with an HLA-matched sibling (groups 2 and 4) had improved DFS. Three-year DFS was 24% in group 3.

CONCLUSION

Allogeneic SCT improved DFS in high-risk ALL in the first CR. Autologous SCT did not confer a significant benefit over chemotherapy for high-risk ALL.

Efficacy of granulocyte and granulocyte–macrophage colony-stimulating factors in the induction treatment of adult acute lymphoblastic leukemia: a multicenter randomized study

In all, 236 adults with newly diagnosed acute lymphoblastic leukemia (ALL) were randomly assigned to receive either granulocyte colony-stimulating factor (G-CSF), or granulocyte-macrophage CSF (GM-CSF), or no CSF during a 4-week 4-drugs induction chemotherapy. Two successive trials were performed. CSFs were given from the last infusion of anthracycline in Trial 1 or from day 4 of induction therapy in Trial 2 until neutrophil recovery. A total of 95 patients were included in the G-CSF group, 67 in the GM-CSF group, and 74 in the control group. Overall, CSFs showed a trend for a reduced incidence of severe infections and of days with antibiotics. Median time for neutrophil recovery was 17 days with G-CSF, 18 days with GM-CSF, and 21 days without CSF. In Trial 2, duration of hospitalization was significantly lower in the G-CSF group than in the other groups (P < 0.05). Time to neutrophil recovery was also significantly shorter (P < 0.05) and severe infections were lower in the G-CSF group (P = 0.01). CR rate was higher in the GM-CSF group as compared to the control group. This tended to be confirmed for the most aggressive ALL and was statistically significant for Philadelphia-positive ALL after salvage therapy (P = 0.04). There were no significant differences between the three groups in terms of disease-free survival.

Adult T-biphenotypic acute leukaemia: clinical and biological features and outcome

Biphenotypic acute leukaemia with T-lymphoid and myeloid markers is rare and poorly documented. In the Leucemie Aigue Lymphoblastique de l'Adulte (LALA) prospective trial (LALA 94) of treatment for adult acute lymphoblastic leukaemia (ALL), seven patients (0.86%) had T-biphenotypic forms. The clinical and biological characteristics and outcome of these seven patients are reported here. The patients' median age was 35 years. At diagnosis, all had a tumoural syndrome and five had a mediastinal mass. In all the cases, leukaemic cells expressed myeloid and lymphoid markers. Two patients (28%) entered complete remission (CR) after induction chemotherapy. Four of the five remaining and assessable patients entered CR after designed salvage chemotherapy with mitoxantrone and high-dose cytosine arabinoside. Three patients are currently in CR. Three patients died, from treatment toxicity in two cases and progressive disease in one case. One patient relapsed 6 months after allogeneic bone marrow transplantation and is still alive. Thus, biphenotypic T-acute leukaemia is clinically frequently associated with mediastinal involvement and the response to conventional chemotherapy used in ALL is poor. However, sustained CR can be achieved by salvage chemotherapy combining an intercalating agent with high-dose cytosine arabinoside, as used in acute myeloid leukaemia.

Should adolescents with acute lymphoblastic leukemia be treated as old children or young adults? Comparison of the French FRALLE-93 and LALA-94 trials

PURPOSE

To compare pediatric and adult therapeutic practices in the treatment of acute lymphoblastic leukemia (ALL) in adolescents.

PATIENTS AND METHODS

From June 1993 to September 1994, 77 and 100 adolescents (15 to 20 years of age) were enrolled in the pediatric FRALLE-93 and adult LALA-94 protocols, respectively. Among the different prognostic factors, we retrospectively analyzed the effect of the trial on achieving complete remission (CR) and event-free survival (EFS).

RESULTS

Patients were younger in the FRALLE-93 than in the LALA-94 protocol (median age, 15.9 v 17.9 years, respectively), but other characteristics were similar, including median WBC count (18 x 10(9) cells/L v 16 x 10(9) cells/L), B/T-lineage (54 of 23 v 72 of 28 patients), CD10-negative ALL (13% v 15%), and poor-risk cytogenetics (t(9;22), t(4;11), or hypodiploidy less than 45 chromosomes: 6% v 5%). The CR rate depended on WBC count (P =.005) and trial (94% v 83% in FRALLE-93 and LALA-94, respectively; P =.04). Univariate analysis showed that unfavorable prognostic factors for EFS were as follows: the trial (estimated 5-year EFS, 67% v 41% for FRALLE-93 and LALA-94, respectively; P <.0001), an increasing WBC count (P <.0001), poor-risk cytogenetics (P =.005), and T-lineage (P =.01). The trial and WBC count remained significant parameters for EFS in multivariate analysis (P <.0001 and P =.0004). Lineage subgroup analysis showed an advantage for the FRALLE-93 trial for CR achievement (98% v 81%; P =.002) and EFS (P =.0002) in B-lineage ALL and for EFS (P =.05) in T-lineage ALL. Age was not a significant prognostic factor in this population of adolescents.

CONCLUSION

This study's findings indicate that adolescents should be included in intensive pediatric protocols and that new trials should be designed, inspired by pediatric protocols, for the treatment of young adults with ALL.

Bone marrow biopsy in adult acute lymphoblastic leukemia: morphological characteristics and contribution to the study of prognostic factors

Bone marrow (BM) sections were examined in 128 untreated adult patients with newly diagnosed acute lymphoblastic leukemia (ALL), seen in our institution over a 19-year period. BM biopsy was performed in order to assess the incidence, degree and prognostic significance of histological data of the disease. BM features studied were reticular fibrosis, total cellularity, residual hematopoiesis, mitotic activity, and blastic infiltration. T-cell lineage ALL were diagnosed in 23% of the cases, while B-cell lineage ALL represented 70% of the cases. There were 7% of non-T-non-B-cell lineage ALL. The percentage of BM leukemic cells was related to cellularity (P=0.02), while it was related to the disappearance of normal cell lines (P<0.0001). BM cellularity was related to the percentage of circulating leukemic cells at diagnosis (P=0.006). Residual hematopoiesis was related to a higher initial granulocyte count (P=0.04) and lower percentage of circulating blasts (P=0.04). The degree of fibrosis was inversely related to that of BM cellularity (P=0.04). All patients, but four, received standard ALL induction chemotherapy according to different successive protocols. In this whole cohort of patients, complete remission (CR) rate was 78%. Median disease-free survival (DFS) and median overall survival (OS) were 13.7 months and 20.2 months, respectively. In univariate analysis, CR rate was positively affected by mitotic activity (P=0.01) and residual hematopoiesis (P=0.008). OS was positively influenced by a higher leukemic cell mitotic activity (P=0.03) and the persistence of more than two residual normal cell lines in BM (P=0.04). Patients presenting with both of those characteristics had better outcome than patients who did not, as well as, in terms of CR (P=0.03), or DFS (P=0.002), or OS (P=0.003). T-cell lineage ALL and L3 ALL did not significantly influence those results. Our findings did not confirm that among marrow features, reticular fibrosis has any prognostic value. A multivariate analysis of both clinical and histological data was performed to test their prognostic relevance. In a model including age, immunophenotype, Philadelphia chromosome status, mitotic index, and level of normal residual hematopoiesis, the only significant predictor of CR achievement were the persistence of normal residual hematopoietic cell lines (P=0.01) and the mitotic activity of leukemic cells (P=0.002). Philadelphia chromosome status (P=0.03) and age (P<0.0001) were of prognostic value, respectively for DFS and OS. We conclude that some characteristics of BM biopsy afford not only descriptive but also prognostic information for predicting the outcome. The persistence of normal residual hematopoiesis and intense leukemic cells mitotic activity were both factors of favorable outcome, while BM fibrosis did not display any prognostic value.

Outcome of treatment in adults with Philadelphia chromosome-positive acute lymphoblastic leukemia--results of the prospective multicenter LALA-94 trial

From 1994 to 2000, 154 adults with Philadelphia chromosome-positive (Ph(+)) and/or BCR-ABL(+) acute lymphoblastic leukemia (ALL) were treated according to a prospective trial (median follow-up, 4.5 years) with the aim to study the prognostic value of early response to therapy and the role of stem cell transplantation (SCT) in first complete remission (CR). All patients received a standard induction course followed by a course of mitoxantrone and intermediate-dose cytarabine (HAM). After each course, minimal residual disease was tested by specific reverse transcriptase-polymerase chain reaction (RT-PCR) (median sensitivity, 10(-5)). Allogeneic SCT (if a donor) or autologous SCT (if not) was planned at 3 months in all patients in CR after HAM. CR rates after induction, after HAM, and at 3 months were 53%, 67%, and 62%, respectively. High leukocyte count and m-bcr subtype were the 2 identified bad-prognosis factors for CR at 3 months, both superseded by a poor early response assessed at day 8 of the induction course. HAM-associated salvage rate was higher in patients with M-bcr than in those with m-bcr ALL (55% vs 30%; P =.05). In the 103 patients eligible for SCT, the existence of a donor and the negative BCR-ABL status after HAM were independently predictive of remission duration (P <.001 and.01, respectively) and survival (P =.02 and.01, respectively). Relapse was the most common cause of treatment failure in all patient groups. Allogeneic SCT in first CR is the current best treatment option in adults with the disease. New strategies must be tested during early phases of therapy to increase the rate of BCR-ABL(-) remissions.

Treatment of acute lymphoblastic leukemia in the elderly: an evaluation of interferon alpha given as a single agent after complete remission

Although interferon (IFN) has been used in elderly patients with acute lymphoblastic leukemia (ALL), the benefits from IFN therapy have not been properly assessed, especially as it was given combined with other cytotoxic drugs, which obscured the role of IFN if any. In 1997, we started a study aimed at improving our previous results in elderly patients with ALL and at assessing the therapeutic role of IFN in this disease. Fifty-eight patients with ALL, aged 55-81 years (median: 64.9 years), were randomly allocated to treatment with vindesine or vincristine during induction. After a first consolidation course, IFN was administered as a single agent for three months together with cranial radiotherapy. Chemotherapy was then resumed with a second consolidation course and maintenance. A complete remission (CR) was obtained in 58% of patients (CI: 45-71%), significantly less than in our previous study which included IFN combined with chemotherapy during maintenance (CR: 85%, CI:70-94%, p = 0.007). Overall survival (median: 289 vs 434 days in the previous study, p = 0.01) and disease-free survival (median: 146 vs 427 days, p = 0.009) were also inferior in the present study. In particular, the pattern of relapses over time suggested that the 3 month IFN treatment phase with no additional chemotherapy might have contributed to the comparatively poor outcome of this cohort. In addition, vindesine given during induction did not prove less neurotoxic than vincristine, did not improve the CR rate, and had no impact on survival. In conclusion, although similar to published studies in elderly patients with ALL, this study is inferior to our previous one. INF, given as a single drug, has a modest role if any in the treatment of older persons with ALL.

Long-term follow-up of patients with newly diagnosed adult acute lymphoblastic leukemia: a single institution experience of 378 consecutive patients over a 21-year period

Although the prospect of long-term leukemia-free survival (LFS) after treatment for adult acute lymphoblastic leukemia (ALL) is widely accepted, few studies have reported long-term survival data. Three hundred and seventy-eight ALL patients, referred to our hospital from 1978 to 1999, were reviewed for long-term follow-up data. The analysis included data on 351 patients treated by standard chemotherapy according to 11 different successive and/or concomitant regimens. Complete remission (CR) was achieved in 299 patients (79%). Initial performance status, LDH level, immunophenotype, age, and risk group (defined according to Hoelzer's criteria) at diagnosis were of significant prognostic value for CR achievement. Median leukemia-free survival (LFS) was 14 months with a 3-year, a 5-year, and an 8-year LFS at 30%, 26%, and 24%, respectively. LFS was better in T cell lineage ALL than in B cell lineage ALL (P = 0.05). Younger age was also a favorable prognostic factor for LFS (P = 0.001). Philadelphia-positive (Ph+) ALL displayed a poor outcome since median LFS was 7 months with only 13% of survival at 3 years. Median overall survival (OS) of the entire cohort was 18 months with a 3-year, a 5-year, and an 8-year OS at 32%, 24%, and 22% respectively. Favorable prognostic factors for OS were younger age (P < 0.0001), and T cell lineage ALL (P = 0.001). Among non-T cell lineage ALL, standard-risk ALL confirmed a significant better outcome than high-risk ALL (P = 0.0003). It was apparent from this analysis that hazard rates for death and relapse were greatest in the first year, decreased substantially between years 1 and 2, then decrease further between years 2 and 3. Rates of death and relapse were quite low after 3-4 years. All patients relapsing after 3 years of CR were B or non-B non-T cell lineage ALL. Long-term survivors (LTS), defined as survival in CR > or =3 years, represented 23% of evaluable patients. Eighty-three patients remain alive in initial CR at >3 years, while only three were LTS after a second CR. Overall, no significant improvement was shown in terms of CR achievement and survival duration over the years. However, regarding survival, a significant improvement was demonstrated in T cell lineage ALL (P = 0.03). Furthermore, patients (aged less than 50 years) transplanted while in first CR did significantly better than those receiving only chemotherapy as post-remission therapy (P < 0.0001). The 3-year OS, after allogeneic transplantation in first CR, was 74% in T cell lineage ALL, while it was less than 50% in B cell lineage ALL. This single center study on a large cohort of ALL patients reflects the degree to which ALL treatment remains unsuccessful in adults. Only T cell lineage ALL outcomes have improved over the years. The results suggest a time (3 years) at which it becomes reasonable to speak of potential cure, provided the patient is in CR.

Allogeneic hematopoietic stem-cell transplantation after nonmyeloablative preparative regimens: impact of pretransplantation and posttransplantation factors on outcome

PURPOSE

To analyze the impact of pre- and posttransplantation factors on the outcome of allogeneic transplantation after nonmyeloablative conditioning regimens.

PATIENTS AND METHODS

Ninety-two allogeneic transplantations after nonmyeloablative preparative regimens were reported to the Société Française de Greffe de Moelle Registry registry. Initial diagnoses were lymphoid diseases (n = 22), myeloma (n = 14), acute leukemia and myelodysplasia (n = 41), chronic myelogenous leukemia (n = 12), and solid tumors (n = 3). Forty-six patients had previously received a transplant, and 49 had progressive disease before transplantation. Three types of conditioning regimens were used with fludarabine or antithymocyte globulins. Eighty-nine patients underwent transplantation, 60 from peripheral-blood progenitor cells. Eighty-six patients received graft-versus-host disease (GHVD) prophylaxis for a median duration of 53 days.

RESULTS

Seventy-nine patients engrafted, with 40 complete and 21 mixed chimerisms. The acute GHVD rate at 3 months was 50% +/- 11%. Fifty-two patients achieved complete remission and 12, partial remission. At 18 months after transplantation, the overall survival (OS) and the transplant-related mortality (TRM) were 32% +/- 12% and 38% +/- 14%, respectively. Initial diagnosis and disease status before transplantation significantly influenced survival. Age and GHVD prophylaxis type significantly influenced TRM. We also showed an impact of GHVD prophylaxis duration on OS and TRM. In multivariate analysis, three factors remained of prognostic value on OS: initial diagnosis, disease status at transplantation, and GHVD prophylaxis duration.

CONCLUSION

This series shows encouraging results from nonmyeloablative conditioning regimens before allotransplantation and demonstrates the impact of some pre- and posttransplantation factors on outcome after transplantation.

Acute lymphoblastic leukemia in the elderly: The Edouard Herriot Hospital experience

Data on all patients with acute lymphoblastic leukemia (ALL) aged 60 or older, referred to our institution over a 18-year period, were studied to determine the incidence and range of clinical and biological subtypes, and the outcome of different therapeutic approaches. Sixty-nine ALL cases (median age: 68 years) were diagnosed between 1980 and 1998 (18% of all adult ALL seen during this period). Ten of them (14%) had a past history of previous malignancy. Karyotypic analysis was performed successfully in 42 cases. Ten patients were diagnosed as Philadelphia chromosome positive (Ph(+)) ALL. Immunophenotyping was performed in 63 cases. Fifty-six patients had B-cell lineage ALL. T lymphoid markers were observed only in 5 cases. Co-expression of myeloid markers was observed in 19% of tested cases. Five patients died before any chemotherapy could be given. All other patients received "curative" treatment according to different protocols used during the period of study. Overall complete remission (CR) rate of these patients was 62% (95% confidence interval (CI): 50-74%). Thirty-nine patients achieved CR after one course of chemotherapy and 4 patients after salvage therapy. Median disease-free survival (DFS) of the entire cohort was 8.3 months (95% CI: 5-12.8 months) and median overall survival was 7 months (95% CI: 6-10 months). In multivariate analysis, the presence of hemorrhage (P = 0.02) was a poor prognostic for CR achievement. Higher WHO performance status (P = 0.003) and the presence of hemorrhage (P = 0.01) at diagnosis were poor prognostics for overall survival. When patients were stratified into three groups according to the time of admission, survival appeared significantly longer for patients admitted between July 1992 and December 1998 (median overall survival at 10 months) than for patients admitted before July 1992 (P = 0.04). "Age-adapted" therapy appeared superior to "young adult-like" therapy in terms of CR rate (96% versus 60%; P = 0.007). However, "age-adapted" therapy did not show any advantage in terms of DFS or overall survival, making the difference in CR rates questionable. We conclude that the pejorative overall outcome in elderly ALL points to the need for new therapeutic trials taking into account the specific characteristics of ALL in this age group.