Persistent MRD before and after allogeneic BMT predicts relapse in children with acute lymphoblastic leukaemia

Minimal residual disease (MRD) during early chemotherapy is a powerful predictor of relapse in acute lymphoblastic leukaemia (ALL) and is used in children to determine eligibility for allogeneic haematopoietic stem cell transplantation (HSCT) in first (CR1) or later complete remission (CR2/CR3). Variables affecting HSCT outcome were analysed in 81 children from the ANZCHOG ALL8 trial. The major cause of treatment failure was relapse, with a cumulative incidence of relapse at 5 years (CIR) of 32% and treatment‐related mortality of 8%. Leukaemia‐free survival (LFS) and overall survival (OS) were similar for HSCT in CR1 (LFS 62%, OS 83%, n = 41) or CR2/CR3 (LFS 60%, OS 72%, n = 40). Patients achieving bone marrow MRD negativity pre‐HSCT had better outcomes (LFS 83%, OS 92%) than those with persistent MRD pre‐HSCT (LFS 41%, OS 64%, P < 0·0001) or post‐HSCT (LFS 35%, OS 55%, P < 0·0001). Patients with B‐other ALL had more relapses (CIR 50%, LFS 41%) than T‐ALL and the main precursor‐B subtypes including BCR‐ABL1, KMT2A (MLL), ETV6‐RUNX1 (TEL‐AML1) and hyperdiploidy >50. A Cox multivariate regression model for LFS retained both B‐other ALL subtype (hazard ratio 4·1, P = 0·0062) and MRD persistence post‐HSCT (hazard ratio 3·9, P = 0·0070) as independent adverse prognostic variables. Persistent MRD could be used to direct post‐HSCT therapy.     

Outcome after first relapse in adult patients with Philadelphia chromosome‐negative acute lymphoblastic leukaemia

To analyse the outcome of adult patients who developed a first relapse of acute lymphoblastic leukaemia (ALL), we collected the clinical data of 332 patients with Philadelphia‐chromosome (Ph) negative ALL, aged 16–65 years, who relapsed after first complete remission (CR1) between 1998 and 2008 in 69 institutions all over Japan, including 58 patients who relapsed after allogeneic haematopoietic stem cell transplantation (Allo‐HSCT) in CR1. The overall survival (OS) was 43·4% at 1 year, and 16·3% at 5 years from relapse in patients who received chemotherapy alone in CR1. Among patients who relapsed after chemotherapy alone in CR1, 123 (52·5%) achieved a second remission (CR2) following salvage chemotherapy, of whom 62 subsequently underwent Allo‐HSCT during CR2. Allo‐HSCT in CR2 was significantly associated with better OS. Moreover, the type of salvage chemotherapy influenced OS from relapse. A doxorubicin, vincristine, and predonisone‐based (AdVP‐type) regimen was related to better OS in patients with longer CR1 (more than 1 year), but was related to worse OS in patients with shorter CR1. In conclusion, the prognosis of patients with relapsed Ph‐negative ALL is poor. Allo‐HSCT after a first relapse could improve the prognosis. Selection of the optimal salvage chemotherapy might depend on the duration of CR1.     

Treatment of children with acute myeloid leukaemia who relapsed after allogeneic haematopoietic stem cell transplantation

Despite improvements in diagnosis and treatment, 30–40% of children with acute myeloid leukaemia (AML) experience relapse. For those who relapse after allogeneic haematopoietic stem cell transplantation (allo‐HSCT), the prognosis is particularly poor, with limited reported literature on these patients. We reviewed the clinical course of 49 children with AML (28 males, 21 females) who received allo‐HSCT between 1993 and 2011, and who had subsequently relapsed. Study endpoints included (i) complete remission (CR) rate after intensive chemotherapy, and prognostic factors for CR, (ii) disease‐free survival (DFS) and overall survival (OS) for patients who achieved CR and (iii) OS for recipients of intensive chemotherapy and prognostic factors for OS . Of the 36 patients who received intensive chemotherapy after post‐HSCT relapse, 26 (72%) achieved CR. For patients who achieved CR, 5‐year DFS and OS were 32·6 ± 10·2% and 44·4 ± 11·1%, respectively. For all recipients of intensive chemotherapy, 5‐year OS was 31·6 ± 8·7%. Cumulative incidence of treatment‐related death was 14·4%. All three recipients of second HSCT died. Amongst prognostic factors predicting improved survival, only disease status at HSCT (early first CR vs. others) proved significant in multivariate study (Hazard Ratio 2·42, 95% Confidence Interval 1·02–5·74, P = 0·045). Treatment with curative intent was able to salvage a minor but important subset of children with AML who relapsed post‐allogeneic transplant.     

Pre‐ and post‐transplant minimal residual disease predicts relapse occurrence in children with acute lymphoblastic leukaemia

Relapse remains the leading cause of treatment failure in children with acute lymphoblastic leukaemia (ALL) undergoing allogeneic haematopoietic stem cell transplantation (HSCT). We retrospectively investigated the prognostic role of minimal residual disease (MRD) before and after HSCT in 119 children transplanted in complete remission (CR). MRD was measured by polymerase chain reaction in bone marrow samples collected pre‐HSCT and during the first and third trimesters after HSCT (post‐HSCT1 and post‐HSCT3). The overall event‐free survival (EFS) was 50%. The cumulative incidence of relapse and non‐relapse mortality was 41% and 9%. Any degree of detectable pre‐HSCT MRD was associated with poor outcome: EFS was 39% and 18% in patients with MRD positivity <1 × 10⁻³ and ≥1 × 10⁻³, respectively, versus 73% in MRD‐negative patients (P < 0·001). This effect was maintained in different disease remissions, but low‐level MRD had a very strong negative impact only in patients transplanted in second or further CR. Also, MRD after HSCT enabled patients to be stratified, with increasing MRD between post‐HSCT1 and post‐HSCT3 clearly defining cohorts with a different outcome. MRD is an important prognostic factor both before and after transplantation. Given that MRD persistence after HSCT is associated with dismal outcome, these patients could benefit from early discontinuation of immunosuppression, or pre‐emptive immuno‐therapy.     

Haematopoietic stem cell transplantation for relapsed or refractory anaplastic large cell lymphoma: a study of children and adolescents in Japan

To evaluate haematopoietic stem cell transplantation (HSCT) in children and adolescents, we reviewed the records of 47 patients who were ≤18 years, had relapsed or refractory anaplastic large cell lymphoma, and received HSCT between 1990 and 2010. At HSCT, complete remission (CR) was less common in allogeneic HSCT recipients (n = 24) than in autologous HSCT recipients (n = 23) (P = 0·01). The autologous and allogeneic HSCT groups differed in terms of 5‐year event‐free survival (EFS) (38% vs. 50%, P = 0·63), cumulative incidence of progress or relapse (49% vs. 28%, P = 0·25), and treatment‐related mortality (12% vs. 25%, P = 0·40). However, these differences were not significant. Patients with non‐CR at autologous HSCT had a significantly lower EFS rate (14% vs. 48%, P = 0·03). Conversely, although those with non‐CR at allogeneic HSCT had a lower EFS rate, this was not significant (44% vs. 63%, P = 0·26). Reduced‐intensity conditioning regimens were used for three of the 16 allogeneic HSCTs received by patients with non‐CR. These three patients achieved CR, surviving 32–65 months after HSCT. These results demonstrated that allogeneic HSCT might be a treatment option for patients who do not achieve CR through conventional chemotherapy.     

Outcomes of treatment for relapsed acute lymphoblastic leukaemia in children with Down syndrome

Children with Down syndrome (DS) have a greater risk for developing both acute lymphoblastic leukaemia (ALL) and significant adverse effects of chemotherapy. We investigated their outcome with, and tolerance of, treatment protocols for relapsed ALL optimized in the paediatric population without DS. Probability of survival and causes of treatment failure were determined for 49 children with DS and a matched cohort of 98 children without DS among 2160 children treated for relapsed ALL in clinical trials conducted by the Berlin‐Frankfurt‐Münster ALL Relapse Study Group between 1983 and 2012. Despite more favourable ALL relapse characteristics, children with DS experienced lower event‐free (EFS) and overall survival (OS) than the control group without DS (EFS 17 ± 08% vs. non‐DS 41 ± 06%, P = 0·006; OS 17 ± 09% vs. non‐DS 51 ± 06%, P < 0·001). Children with DS developed more frequently fatal complications of treatment (34 ± 07% vs. non‐DS 10 ± 04%, P < 0·001). During the last decade, EFS and OS were no longer significantly different in children with and without DS (EFS 31 ± 09% vs. 36 ± 09%, P = 0·399; OS 31 ± 12% vs. 53 ± 09%, P = 0·151). DS proved an independent prognostic factor of outcome after ALL relapse. Induction deaths and treatment‐related mortality but not subsequent relapse were the main barrier to successful outcomes of relapse therapy in children with DS.     

DV‐ICE,intensive induction and early transplantation for adult patients with acute lymphoblastic leukemia: a phase II study

Objectives: Eighty percent of adult patients with acute lymphoblastic leukemia (ALL) achieve a complete remission (CR) but only 30–40% are long term survivors. Best treatment strategies remain to be defined. The role of induction intensity, first remission hematopoietic stem cell transplantation (HSCT) and maintenance chemotherapy continues to be discussed. We tested a strategy of high intensity treatment of short duration followed by HSCT. Patients and methods: This prospective phase II study used induction with DV‐ICE followed by immediate allogeneic or autologous HSCT (depending on donor availability) without additional consolidation or maintenance treatment. DV‐ICE consisted of dexamethasone, vincristine, idarubicin, etoposide, and conventional dose cytosine arabinoside; HSCT was planned immediately if CR was achieved or after an additional course of intermediate high dose cytosine arabinoside and etoposide for patients with induction failure. A total of 42 consecutive patients between 17 and 67 yr of age (median 43 yr) were enrolled. Of the 42 patients, 57% were male, 76% had B‐lineage ALL, 19% T‐lineage ALL and two patients biphenotypic ALL. 29% were Ph+; 7% had 11q23 and 45% had a normal karyotype. CNS involvement was found in three patients. Results: Thirty‐three patients (79%) achieved a CR, 24 patients after induction I or II and nine patients after rescue HSCT. 31 patients received a HSCT (seven autologous and 24 allogeneic). 11 patients did not receive a HSCT because of early death in nine (treatment toxicity in five, refractory disease in four), one patient refused transplantation, one patient was not suitable. Disease‐free survival (DFS) of the entire cohort was 46% (95% CI ±16%) at 1 yr and 16% (±13%) at 5 yr. Overall survival (OS) was 63% (±15%) at 1 yr and 23% (±15%) at 5 yr, with a median follow‐up of surviving patients of 55 (4–136) months. Neither disease subtype, cytogenetic abnormalities nor patient age or gender was significantly associated with survival. Conclusions: Intensive induction using DV‐ICE followed by early transplantation without treatment beyond 4 months failed to improve outcome compared with standard treatment.     

Secondary acute lymphoblastic leukaemia is constitutional and probably not related to prior therapy

Very little is known about secondary acute lymphoblastic leukaemia (s‐ALL). This retrospective analysis studied a cohort of s‐ALL patients treated at a single centre between 1994 and 2013, while comparing therapy‐associated ALL (t‐ALL) and antecedent malignancy ALL (am‐ALL) patients. Thirty‐two patients with s‐ALL were identified. The overall incidence was 9·4% among ALL adults while T‐cell s‐ALL was rare (12% of s‐ALLs). The median time interval between two malignant diagnoses was 5·3 years (range: 0·1–28). In contrast to previous reports, most of the s‐ALLs were CD10 +  and without KMT2A (MLL) abnormalities. The overall survival (OS) rates of the entire cohort at 12 and 24 months from ALL diagnosis was 49% and 25%, respectively. Most patients (n = 23, 72%) received prior chemo‐/radio‐therapy for their first malignancy (t‐ALL) and only 9 (28%) did not (am‐ALL). No significant difference was found in the incidence of B‐/T‐ lineage ALL, extramedullary disease, blood count, and the rate of Philadelphia‐positive ALL, nor in the rates of complete remission (P = 0·55) and OS (P = 0·97). This similarity, together with high incidence of family malignancy in both groups, raise the possibility that s‐ALL patients may have an inherent predisposition to malignancies and a history of previous therapy may be of lesser importance in the pathogenesis of s‐ALL.     

Blinatumomab and inotuzumab for B cell precursor acute lymphoblastic leukaemia in children: a retrospective study from the Leukemia Working Group of the Spanish Society of Pediatric Hematology and Oncology (SEHOP)

Blinatumomab and inotuzumab ozogamycin represent promising alternatives to conventional chemotherapy in acute lymphoblastic leukaemia (ALL). We analysed data from 29 children with ALL treated under compassionate use with blinatumomab, inotuzumab or both. The complete remission (CR) rate in a heavily pretreated population with overt relapse was 47·6%. At earlier stages (first/second CR), both antibodies represented a useful tool to reduce minimal residual disease, and/or avoid further toxic chemotherapy until stem cell transplantation. Six patients developed grade 3 reversible non-haematological toxicity. The 12-month overall survival and event-free survival rates were 50·8 ± 26·4% and 38·9 ± 25·3% with blinatumomab, 45·8 ± 26% and 27·5 ± 25% with inotuzumab.     

Haploidentical transplantation compared with matched sibling and unrelated donor transplantation for adults with standard‐risk acute lymphoblastic leukaemia in first complete remission

We retrospectively investigated outcomes of haploidentical donor (HID) transplant for adults with standard‐risk acute lymphoblastic leukaemia (ALL) in first complete remission (CR1) compared with human leucocyte antigen (HLA)‐matched sibling donor (MSD) and HLA‐matched unrelated donor (MUD) transplants. A total of 348 adult patients were enrolled, including 127 HID, 144 MSD and 77 MUD recipients. The cumulative incidence of grade II–IV acute graft‐versus‐host disease (aGVHD) was 39·5%, 24·0% and 40·3% for HID, MSD and MUD, respectively (P = 0·020). However, there was no difference in grade III–IV aGVHD (11·4%, 7·7%, 13·5%, respectively, P = 0·468). The 5‐year cumulative transplant‐related mortality was 16·4%, 11·6% and 19·6% (P = 0·162), the 5‐year relapse rate post‐transplantation was 14·8%, 21·1% and 16·7% (P = 0·231), the 5‐year overall survival was 70·1%, 73·7% and 69·8% (P = 0·525), and the 5‐year disease‐free survival was 68·7%, 67·3% and 63·7%, respectively (P = 0·606). Furthermore, the 3‐year GVHD‐free, relapse‐free survival was not different (50·8%, 54·9% and 52·2%, respectively, P = 0·847). Our results indicate that the outcomes of HID transplants are equivalent to those of MSD and MUD, and that HID transplantation is a valid alternative for standard‐risk adults with ALL in CR1 who lack matched donors.     

Intermediate dose of imatinib in combination with chemotherapy followed by allogeneic stem cell transplantation improves early outcome in paediatric Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL): results of the Spanish Cooperative Group SHOP studies ALL-94, ALL-99 and ALL-2005

Philadelphia‐chromosome acute lymphoblastic leukaemia (Ph+ ALL) is a subgroup of ALL with very high risk of treatment failure. We report here the results of the Sociedad Española de Hematología y Oncología Pediátricas (SEHOP/SHOP) in paediatric Ph+ ALL treated with intermediate‐dose imatinib concurrent with intensive chemotherapy. The toxicities and outcome of these patients were compared with historical controls not receiving imatinib. Patients with Ph+ ALL aged 1–18 years were enrolled in three consecutive ALL/SHOP trials (SHOP‐94/SHOP‐99/SHOP‐2005). In the SHOP‐2005 trial, imatinib (260 mg/m² per day) was given on day‐15 of induction. Allogeneic haematopoietic stem‐cell transplantation (HSCT) from a matched related or unrelated donor was scheduled in first complete remission (CR1). Forty‐three patients were evaluable (22 boys, median age 6·8 years, range, 1·2–15). Sixteen received imatinib whereas 27 received similar chemotherapy without imatinib. Seventeen of 27 and 15 of 16 patients in the non‐imatinib and imatinib cohort, respectively, underwent HSCT in CR1. With a median follow‐up of 109 and 39 months for the non‐imatinib and imatinib cohorts, the 3‐year event‐free survival (EFS) was 29·6% and 78·7%, respectively (P = 0·01). These results show that, compared to historical controls, intermediate dose of imatinib given concomitantly with chemotherapy and followed by allogeneic HSCT markedly improved early EFS in paediatric Ph+ ALL.     

Outcome of children with acute myeloid leukaemia (AML) experiencing primary induction failure in the AIEOP AML 2002/01 clinical trial

Paediatric patients with acute myeloid leukaemia (AML) who fail induction due to primary resistance to chemotherapy account for a significant proportion of cases and have a particularly dismal prognosis. We report the clinical and biological data, and final outcome of 48 paediatric patients with primary‐resistant AML enrolled in the Associazione Italiana di Ematologia e Oncologia Pediatrica AML 2002/01 clinical trial. These patients had a significantly higher white blood cell count at diagnosis compared to other AML patients. Cytogenetic and molecular features did not differ between patients with primary induction failure and patients allocated to the high‐risk group. For the whole patient population, the probability of overall survival, event‐free survival (EFS) and disease‐free survival (DFS) was 21·8% ± 6·2, 20·4% ± 5·9, and 49·5% ± 11·3, respectively. Twenty‐eight (58%) patients received haematopoietic stem cell transplantation (HSCT); 3 were autologous and 25 were allogeneic. Patients who underwent HSCT had improved EFS (31·2% vs. 5%, P < 0·0001). Only one of the 20 patients who did not receive HSCT is alive and disease free. The 19 patients in complete remission at time of HSCT showed significantly better DFS than the 9 with active disease (46% vs. 0%, P = 0·02). This study represents one of the largest series with long‐term follow up of paediatric AML patients with primary refractory disease. Children who underwent transplantation had an encouraging long‐term outcome. Disease recurrence remains the major cause of treatment failure; a better understanding of the disease biology is desirable to develop more effective treatment strategies.     

Outcome for children and young people with Early T‐cell precursor acute lymphoblastic leukaemia treated on a contemporary protocol,UKALL 2003

We investigated the outcome for children and young people with Early T‐precursor acute lymphoblastic leukaemia (ETP‐ALL), a recently described poor prognosis sub‐group of T‐ALL, treated on a contemporary protocol, UKALL 2003. After a median follow‐up of 4 years and 10 months, the ETP sub‐group, representing 16% of T‐ALL patients, had non‐significantly inferior 5‐year event‐free survival (76·7% vs. 84·6%, P = 0·2) and overall survival (82·4% vs. 90·9%, P = 0·1), and a higher relapse rate (18·6% vs. 9·6%, P = 0·1) compared to typical T‐ALL. ETP‐ALL has an intermediate risk outcome, which does not warrant experimental treatment or first remission allogeneic transplant for the group universally.     

Long-term outcome evaluation of medium/high risk acute lymphoblastic leukaemia children treated with or without cranial radiotherapy in the EORTC 58832 randomized study

We investigated the long-term outcome, the incidence of second neoplasms (SN) and the rate of late adverse effects (LAE) in children with central nervous system (CNS) negative medium/high-risk de novo acute lymphoblastic leukaemia (ALL), in first complete remission (CR1) at end of late intensification, randomized to receive no cranial radiotherapy (No CRT, n = 92) versus CRT (standard arm, n = 84) in the non-inferiority EORTC 58832 study (1983–1989). Median follow-up was 20 years (range 4–32 years). The 25-year disease-free survival rate (±SE) was 67·4 ± 4·9% without CRT and 70·2 ± 5·0% with CRT. The 25-year incidence of isolated (6·5 ± 2·6% vs. 4·8 ± 2·3%) and any CNS relapse {8·7 ± 2·9% vs. 11·9 ± 3·5%; hazard ratio (HR) 0·71 [95% confidence interval (CI) 0·28–1·79]; test of non-inferiority: P = 0·01} was not increased without CRT. The 25-year SN incidence in CR1 was 7·9 ± 4·6% vs. 11·0 ± 4·2%. The 25-year event-free and overall survival rates were quite similar in both arms [59·5 ± 6·3% vs. 60·5 ± 5·9%, HR 0·94 (95% CI 0·57–1·52), and 78·1 ± 4·3% vs. 78·5 ± 4·5%, HR 1·00 (95% CI 0·53–1·88)]. Omission of CRT was associated with dramatic decrease in CNS and endocrine LAE rates. In conclusion, our data suggest that, with proper systemic and intrathecal CNS prophylaxis, CRT could totally be omitted in CR1 without jeopardizing survival, while decreasing LAE in childhood ALL.     

Safety and efficacy of nelarabine in children and young adults with relapsed or refractory T‐lineage acute lymphoblastic leukaemia or T‐lineage lymphoblastic lymphoma: results of a phase 4 study

Nelarabine is an antineoplastic agent approved for the treatment of relapsed/refractory T‐lineage acute lymphoblastic leukaemia (T‐ALL) or T‐lineage acute lymphoblastic lymphoma (T‐LBL). The purpose of this phase 4, multicentre, single‐arm, observational, open‐label trial was to provide additional data on the safety and efficacy of nelarabine under licensed conditions of use in children and young adults ≤21 years of age. Patients (N = 28) had a mean ± standard deviation age of 11·5 ± 4·6 years; 71% were male and 61% had a diagnosis of T‐ALL. Adverse events (AEs) and treatment‐related AEs were experienced by 46% and 21%, respectively, and included few haematological AEs and no haematological serious AEs. Neurological AEs from one of four predefined categories (peripheral and central nervous systems, mental status change and uncategorized) were reported in four patients. There were no AE‐related treatment discontinuations/withdrawals. The overall response rate was 39.3%: complete response (CR), 35.7%; CR without full haematological recovery (CR*), 3.6%. Post‐treatment stem cell transplantation was performed for 46% of the cohort. Median overall survival (OS) was 3·35 months for non‐responders and not reached for responders (CR + CR*). The response rate, median OS, and safety profile of nelarabine in this disease setting and population were consistent with those reported previously.     

Leukaemia relapse after allogeneic transplants for acute myeloid leukaemia: predictive role of WT1 expression

We assessed WT1 expression (expressed as messenger copies/10⁴ ABL1) from marrow cells of 122 patients with acute myeloid leukaemia (AML), before and after an unmanipulated allogeneic haemopoietic stem cell transplant (HSCT). The median age was 44 years (15–69), 59% were in first remission, 74% received a myeloablative conditioning regimen and the median follow up was 865 d (34–2833). Relapse was higher in 67 patients with WT1 expression, at any time post‐HSCT, exceeding 100 copies (54%), as compared to 16%, for 55 patients with post‐HSCT WT1 expression <100 copies (P < 0·0001). Similarly, actuarial 5‐year survival (OS) was 40% vs. 63%, respectively (P = 0·03). In multivariate Cox analysis, WT1 expression post‐HSCT was the strongest predictor of relapse (Hazard Ratio [HR] 4·5, P = 0·0001), independent of disease phase (HR 2·3, P = 0·002). Donor lymphocyte infusions (DLI) were given to 17 patients because of increasing WT1 levels: their OS was 44%, vs. 14% for 21 patients with increasing WT1 expression who did not receive DLI (P = 0·004). In conclusion, WT1 expression post‐HSCT is a strong predictor of leukaemia relapse and survival in AML; WT1 may be used as a marker for early interventional therapy.     

The combination of bortezomib with chemotherapy to treat relapsed/refractory acute lymphoblastic leukaemia of childhood

Achieving complete remission (CR ) in childhood relapsed/refractory acute lymphoblastic leukaemia (ALL ) is a difficult task. Bortezomib, a proteasome inhibitor, has in vitro activity against ALL blasts. A phase I‐II trial, reported by the Therapeutic Advances in Childhood Leukaemia and Lymphoma (TACL ) consortium, demonstrated that bortezomib with chemotherapy has acceptable toxicity and remarkable activity in patients with relapsed ALL failing 2–3 previous regimens. We evaluated bortezomib in combination with chemotherapy in 30 and 7 children with B‐cell precursor (BCP ) and T‐cell ALL , respectively. Bortezomib (1·3 mg/m²/dose) was administered intravenously on days 1, 4, 8, and 11. Chemotherapy agents were the same as those used in the TACL trial, consisting of dexamethasone, doxorubicin, vincristine and pegylated asparaginase. Three patients (8·1%) died due to infections. Twenty‐seven patients (72·9%) achieved CR or CR with incomplete platelet recovery (CR p). Fourteen had minimal residual disease (MRD ) lower than 0·1%. Twenty‐two of 30 BCP ‐ALL patients (73·3%) and 5/7 patients (71%) with T‐cell ALL achieved CR /CR p. The 2‐year overall survival (OS ) is 31·3%; CR /CR p patients with an MRD response had a remarkable 2‐year OS of 68·4%. These data confirm that the combination of bortezomib with chemotherapy is a suitable/effective option for childhood relapsed/refractory ALL .     

Outcome of Down syndrome associated acute lymphoblastic leukaemia treated on a contemporary protocol

We report the outcome for children and young people with Down syndrome‐associated acute lymphoblastic leukaemia (DS‐ALL) treated on a contemporary protocol. Compared with non‐DS ALL, patients with DS‐ALL had an inferior event‐free survival (65·6% vs. 87·7% at 5 years; P < 0·00005) and overall survival (70·0% vs. 92·2%; P < 0·00005). Excess treatment‐related mortality – was primarily responsible for the worse outcomes for DS‐ALL (21·6% at 5 years, vs. 3·3%, P < 0·00005). Minimal residual disease (MRD) risk status was highly discriminant for relapse in DS patients with 0/28 relapses in the MRD low risk group.     

At three years,patients with acute lymphoblastic leukaemia are still at risk for relapse. Results of the international MRC UKALLXII/ECOG E2993 trial

Late relapse [>3 years from complete remission (CR)] in acute lymphoblastic leukaemia (ALL), is unusual. Data from the MRC UKALLXII/ECOG E2993 trial are presented to evaluate the incidence and characteristics of late relapse in adult ALL. Of 1,909 patients, 1,752 (92%) achieved CR and among these 757 (43·2%) relapsed; 691 (91·3%) within three years and 66 (8·7%) beyond. Among these 66 patients, median time to relapse was 47 (37–144) months. Relapse beyond three years occurred in 3·8% of all who achieved CR. The cumulative risk of relapse was 40%, 43% and 45% at three, five and ten years respectively. Out of the 1 752 patients who achieved CR, 11·7% underwent autologous and 40·6% allogeneic transplant, while in CR1. Of the autologous patients, 43·2% relapsed early and 3·4% relapsed late. However, among the allogeneic patients, 13·2% relapsed early and only 1·3% late. The five-year overall survival from relapse was 5·8% and 20% in the early and late relapse patients respectively. In conclusion, late relapse in adults with ALL is not uncommon, and is associated with better outcome after relapse compared to early relapse.     

Minimal residual disease assessed by multi‐parameter flow cytometry is highly prognostic in adult patients with acute lymphoblastic leukaemia

The prognostic value of minimal residual disease (MRD) assessed by multi‐parameter flow cytometry (MFC) was investigated among 340 adult patients with B‐cell acute lymphoblastic leukaemia (B‐ALL) treated between 2004 and 2014 using regimens including the hyperCVAD (hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone, methotrexate, cytarabine) backbone. Among them, 323 (95%) achieved complete remission (CR) and were included in this study. Median age was 52 years (range, 15–84). Median white blood cell count (WBC) was 9·35 × 10⁹/l (range, 0·4–658·1 ×1 0⁹/l). MRD by MFC was initially assessed with a sensitivity of 0·01%, using a 15‐marker, 4‐colour panel and subsequently a 6‐colour panel on bone marrow specimens obtained at CR achievement and at approximately 3 month intervals thereafter. MRD negative status at CR was associated with improved disease‐free survival (DFS) and overall survival (OS) (P = 0·004 and P = 0·03, respectively). Similarly, achieving MRD negative status at approximately 3 and 6 months was associated with improved DFS (P = 0·004 and P < 0·0001, respectively) and OS (P = 0·004 and P < 0·0001, respectively). Multivariate analysis including age, WBC at presentation, cytogenetics (standard versus high risk) and MRD status at CR, 3 and 6 months, indicated that MRD negative status at CR was an independent predictor of DFS (P < 0·05). Achievement of an MRD negative state assessed by MFC is an important predictor of DFS and OS in adult patients with ALL.