To assess the efficacy of an original DAC-7 regimen: daunorubicine (DNR) 60 mg/m 2 /day, days 1-3; cytarabine (AraC) 200 mg/m 2 /day, days 1-7; cladribine (2-CdA) 5 mg/m 2 /day, days 1-5, 400 untreated adult acute myeloid leukemia patients (including 63 with preceding myelodysplastic syndrome), aged 45 (16-60) years were randomized to either DAC-7 (n ¼ 200) or DA-7 (without 2-CdA, n ¼ 200). The overall CR rate equaled 72% for DAC-7 and 69% for DA-7 arm (P ¼ NS). After a single course of DAC-7 induction, the CR rate equaled 64% and was significantly higher compared to 47% in the DA-7 arm (P ¼ 0.0009). Median hospitalization time during the induction was 7 days shorter for DAC-7 compared to the DA-7 group (33 vs 40 days, P ¼ 0.002). Toxicity was comparable in both groups. The probability of 3-year leukemia-free survival (LFS) for DAC-7 and DA-7 group equaled 43 and 34%, respectively (P ¼ NS). There was a trend toward higher LFS rate for patients aged 440 years receiving DAC-7 compared with DA-7 regimen (44 vs 28%, P ¼ 0.05). This study proves that addition of 2-CdA increases antileukemic potency of DNR þ AraC regimen, thus resulting in a higher CR rate after one induction cycle when compared to DA-7, without additional toxicity. It shortens hospitalization time and may improve long-term survival in patients aged 440 years.

SummaryThe treatment of adults with Philadelphia-negative acute lymphoblastic leukaemia (ALL) depends on the presence of risk factors including age, white blood cell count, immunophenotype and time to complete remission. In recent years, status of minimal residual disease (MRD) has been postulated as an additional risk criterion. This study prospectively evaluated the significance of MRD. Patients were treated with a uniform Polish Adult Leukemia Group (PALG) 4-2002 protocol. MRD status was assessed after induction and consolidation by multiparametric flow cytometry. Out of 132 patients included (age, 17-60 years), 116 patients were suitable for analysis. MRD level ‡0AE1% of bone marrow cells after induction was found to be a strong and independent predictor for relapse in the whole study population (P < 0AE0001), as well as in the standard risk (SR, P = 0AE0003) and high-risk (P = 0AE008) groups. The impact of MRD after consolidation on outcome was not significant. The combination of MRD status with conventional risk stratification system identified a subgroup of patients allocated to the SR group with MRD <0AE1% after induction who had a very low risk of relapse of 9% at 3 years as opposed to 71% in the remaining subjects (P = 0AE001). We conclude that MRD evaluation after induction should be considered with conventional risk criteria for treatment decisions in adult ALL.

In this prospective randomized trial, we compared the efficacy and toxicity of cladribine (2-CdA) alone to 2-CdA combined with cyclophosphamide (CC) or cyclophosphamide and mitoxantrone (CMC) in untreated progressive chronic lymphocytic leukemia (CLL). Study end points were complete response (CR), overall response, minimal residual disease (MRD), progression-free survival, overall survival, and toxicity. From January 1, 1998 to December 31, 2003, 508 patients from 15 hematology departments were randomized. Compared with 2-CdA, CMC induced higher CR rate (36% vs 21%, P ‫؍‬ .004), and a trend for higher CR rate with CC was observed (29% vs 21%, P ‫؍‬ .08). Furthermore, the percentage of patients who were in CR and were MRD negative was higher in CMC compared with 2-CdA (23% vs 14%, P ‫؍‬ .042). There were no differences in overall response, progressionfree survival, and overall survival among treatment groups. Grade 3/4 neutropenia occurred more frequently in CC (32%) and CMC (38%) than in 2-CdA (20%) (P ‫؍‬ .01 and P ‫؍‬ .004, respectively). Infections were more frequent in CMC compared with 2-CdA (40% vs 27%, P ‫؍‬ .02).In conclusion, CMC used in first-line treatment of CLL results in a higher CR rate and suppresses MRD more efficiently than 2-CdA monotherapy, although associates with increased toxicity. No important differences in efficacy and toxicity were found between CC and 2-CdA regimens.

Blood group incompatibility between donor and recipient of allogeneic stem cell transplants may be associated with post-transplant erythroid aplasia. A total of 548 patients (pts) received allogeneic transplant for malignant and non-malignant hematologic disorders. In a retrospective analysis, the prevalence and outcome of pure red-cell aplasia (PRCA) in 44 pts with major and bi-directional ABO-mismatch were investigated. Bone marrow grafts were major ABO incompatible in 30 pts; there was bi-directional mismatch in the remaining 14 pts. The median number of transplanted mononuclear cells (NC) was 4.74 x 10(8)/kg (range 0.1-26.4) including CD34+ cells, 3.02 x 10(6)/kg (range 0.9-21.7). Granulocyte engraftment >0.5 x 10e9/l occurred after a median of 21 days (7-32), and platelet exceeded >50 x 10e9/l after a median of 23.5 days (12-109). Acute and chronic graft vs host disease (GVHD) developed in 23 (52%) and 26 (59%) of the patients, respectively. Six (13%) patients transplanted with major and bi-directional ABO-incompatibility developed PRCA. The treatment of PRCA consisted of plasmapheresis (PEX), rapid cyclosporine (CsA) discontinuation, donor lymphocyte infusions (DLI), erythropoietin (EPO), azathioprine, and rituximab. The therapy resulted in erythroid recovery in five out of six patients after a median of 13 months (range 3-16). The median number of transfused red blood cells (RBCs) was 36 U (range 8-57). With a median follow-up of 37 months, the 5-year probability of overall survival (OS) for the PRCA group was 66%. Major ABO mismatch may lead to delayed donor erythroid engraftment. It results in long-term transfusion dependence and, therefore, the risk of iron overload. The therapy is long lasting, but usually effective in majority of patients.

SummaryHypereosinophilic syndrome (HES) is defined as chronic, unexplained hypereosinophilia with organ involvement. A subset of HES patients presents an interstitial deletion in chromosome 4q12, which leads to the expression of an imatinib‐responsive fusion gene, FIP1L1‐PDGFRA. These patients are diagnosed as chronic eosinophilic leukaemia (CEL). We treated seven CEL and HES patients, six of which expressed FIP1L1‐PDGFRA, with imatinib using initial daily doses ranging from 100 to 400 mg. In a remission maintenance phase, the patients were treated with imatinib once weekly. All imatinib‐treated patients achieved a complete haematological remission (CHR), and five of the six patients with FIP1L1‐PDGFRA expression exhibited molecular remission. The decreased imatinib doses were as follows: 200 mg/week in three patients, 100 mg/week in two patients and 100 mg/d in the remaining two patients. For remission maintenance, imatinib doses were set at 100 mg/week in five patients and 200 mg/week in two patients. At a median follow‐up of 30 months all patients remained in CHR and FIP1L1‐PDGFRA expression was undetectable in five of the six FIP1L1‐PDGFRA‐expressing patients. These data suggest that a single weekly dose of imatinib is sufficient to maintain remission in FIP1L1‐PDGFRA‐ positive CEL patients.