MTHFR, TS and XRCC1 genetic variants may affect survival in patients with myelodysplastic syndromes treated with supportive care or azacitidine.

We evaluated the impact of genomic polymorphisms in folate-metabolizing, DNA synthesis and DNA repair enzymes on the clinical outcome of 108 patients with myelodysplastic syndromes (MDS) receiving best supportive care (BSC) or azacitidine. A statistically significant association between methylenetetrahydrofolate reductase (MTHFR) 677T/T, thymidylate synthase (TS) 5'-untranslated region (UTR) 3RG, TS 3'-UTR -6 bp/-6 bp, XRCC1 399G/G genotypes and short survival was found in patients receiving BSC by multivariate analysis (P<0.001; P=0.026; P=0.058; P=0.024). MTHFR 677T/T, TS 3'-UTR -6 bp/-6 bp and XRCC1 399G/G genotypes were associated with short survival in patients receiving azacitidine by multivariate analysis (P<0.001; P=0.004; P=0.002). We then performed an exploratory analysis to evaluate the effect of the simultaneous presence of multiple adverse variant genotypes. Interestingly, patients with ⩾1 adverse genetic variants had a short survival, independently from their International Prognostic Scoring System (IPSS) and therapy received. To our knowledge, this is the first study showing that polymorphisms in folate-metabolizing pathway, DNA synthesis and DNA repair genes could influence survival of MDS patients.

Clofarabine in combination with a standard remission induction regimen (cytosine arabinoside and idarubicin) in patients with previously untreated intermediate and bad-risk acute myelogenous leukemia (AML) or high-risk myelodysplastic syndrome (HR-MDS): phase I results of an ongoing phase I/II study of the leukemia groups of EORTC and GIMEMA (EORTC GIMEMA 06061/AML-14A trial).

This study aims to determine the maximum tolerated dose (MTD) of clofarabine combined with the EORTC-GIMEMA 3 + 10 induction regimen (idarubicin + cytosine arabinoside) in adults with untreated acute myelogenous leukemia or high-risk myelodysplastic syndrome. In this phase I trial, 25 patients (median age 56 years) received 5 days of clofarabine as 1-h infusion (arm A) or push injection (arm B) at the dose level of 5 × 10 or 5 × 15 mg/m(2)/day in an algorithmic dose escalation 3 + 3 design. A consolidation course (intermediate dose cytosine arabinoside, idarubicin) was planned for patients in complete remission (CR). Primary endpoint was safety and tolerance as measured by dose limiting toxicity (DLT); secondary endpoints were response rate, other grade III/IV toxicities, and hematological recovery after induction and consolidation. Five DLTs were observed (in arm A: one DLT at 10 mg/m(2)/day, three at 15 mg/m(2)/day; in arm B: one DLT at 15 mg/m(2)/day). Three patients receiving 15 mg/m(2)/day were withdrawn due to adverse events not classified as DLT. Prolonged hypoplasia was observed in five patients. CR + complete remission with incomplete recovery were achieved in 21 patients (11/12 (92 %) receiving clofarabine 10 mg/m(2)/day; 10/13 (77 %) receiving clofarabine 15 mg/m(2)/day). Clofarabine, 5 × 10 mg/m(2)/day, resulted in one DLT and no early treatment withdrawals. MTD of clofarabine combined with cytosine arabinoside and idarubicin is 5 × 10 mg/m(2)/day.

Investigating factors associated with adherence behaviour in patients with chronic myeloid leukemia: an observational patient-centered outcome study.

BACKGROUND: Optimal adherence to imatinib therapy is of paramount importance to maximise treatment effectiveness in patients with chronic myeloid leukaemia (CML). The main objective of this study was to investigate patient-reported personal factors associated with adherence behaviour. METHODS: Analysis was conducted on 413 CML patients receiving long-term therapy with imatinib. Adherence behaviour was measured with the Morisky Medication Adherence Scale and personal factors investigated included: quality of life, perceived social support, fatigue, symptom burden, psychological wellbeing and desire for additional information. Key socio-demographic and treatment-related factors were also taken into account. Univariate and multivariate logistic regression analyses were used to investigate factors associated with optimal adherence to therapy. RESULTS: In all, 53% of patients reported an optimal adherence behaviour. The final multivariate model retained the following variables as independent predictors of optimal adherence to therapy: desire for more information (ref. no), odds ratio (OR)=0.43 (95% confidence interval (CI), 0.29-0.66; P<0.001), social support (higher score representing greater support), OR=1.29 (95% CI, 1.11-1.49; P<0.001) and concomitant drug burden (ref. no), OR=1.82 (95% CI, 1.18-2.80; P=0.006). CONCLUSION: This study suggests that a higher level of social support, satisfaction with information received and concomitant drug burden are the main factors associated with greater adherence to long-term imatinib therapy.

Gemtuzumab ozogamicin (Mylotarg) as single-agent treatment for frail patients 61 years of age and older with acute myeloid leukemia: final results of AML-15B, a phase 2 study of the European Organisation for Research and Treatment of Cancer and Gruppo Italiano Malattie Ematologiche dell'Adulto Leukemia Groups.

The therapeutic activity and toxicity profile of gemtuzumab ozogamicin were assessed in 40 patients >60 years of age with acute myeloid leukemia (AML) who were not considered eligible for conventional chemotherapy because of advanced age or poor performance status. The drug was administered at the dose of 9 mg/m2 as a single 2-h i.v. infusion on days 1 and 15. Patients who achieved a complete remission (CR/CRp) were to receive a consolidation with two additional injections of the immunotoxin at the same dose. The overall CR/CRp rate was 17% (95% CI, 8-32%). The CR/CRp rate in patients 61-75 years old was 33% (6/18), and 5% (1/22) in patients older than 75 years. Induction death occurred in seven patients (17%), all aged above 75 years. Overall survival was significantly longer in patients aged 61-75 years than in older individuals (P=0.05), and in CD33+ cases than in CD33- cases (P=0.05). We conclude that the dose/schedule of gemtuzumab ozogamicin used in this trial is too toxic in the age group over 75 years. For these patients, additional studies with reduced doses of the immunotoxin are warranted.

High-dose chemotherapy followed by autologous bone marrow transplantation versus dexamethasone, cisplatin, and cytarabine in aggressive non-Hodgkin's lymphoma with partial response to front-line chemotherapy: a prospective randomized italian multicenter study.

PURPOSE: To evaluate, in a prospective multicentric study, the efficacy of a conventional salvage chemotherapy (dexamethasone, cisplatin, and cytarabine [DHAP]) versus high-dose chemotherapy (carmustine, etoposide, cytarabine, and cyclophosphamide [BEAC]) followed by autologous bone marrow transplantation (ABMT) in patients with aggressive non-Hodgkin's lymphoma (NHL) in clinical partial response (PR) after two thirds of a conventional front-line therapy. PATIENTS AND METHODS: From August 1988 to August 1991, 286 patients with aggressive NHL were randomized in seven Italian institutions to receive fluorouracil, methotrexate, cytarabine, cyclophosphamide, doxorubicin, vincristine, and prednisone (F-MACHOP) or methotrexate with leucovorin, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B) as front-line therapy. Of the 286 patients enrolled onto the trial, 77 (27%) were considered in PR after two thirds of the front-line therapy, and 49 of 77 (64%) were randomized: 27 to receive DHAP chemotherapy and 22 to receive BEAC followed by ABMT. RESULTS: The response after second-line treatment was as follows: in the DHAP group, four patients (15%) achieved a complete remission (CR), 12 (44%) remained in stable PR, and 11 (41%) showed progressive disease; in the ABMT group, three patients (14%) obtained a CR, 18 (82%) obtained a stable PR, and one (4%) progressed, with an overall response (CR + stable PR) of 59% and 96% (P < .001) in the DHAP and ABMT groups, respectively. The overall survival was 59% versus 73% and the progression-free survival (PFS) was 52% versus 73% in the DHAP and ABMT groups, respectively (P, not significant). The toxicity was mild, particularly in the ABMT group, and no treatment-related deaths occurred in either group. CONCLUSION: Because of the small number of patients randomized, we were unable to determine whether ABMT or a standard salvage regimen (DHAP) is superior for PR patients. However, we confirmed that myeloablative treatment is a safe and well-tolerated procedure in this category of patients and this may enable us to evaluate its role as part of a front-line treatment in poor-risk NHL patients.

Extramedullary involvement at relapse in acute promyelocytic leukemia patients treated or not with all-trans retinoic acid: a report by the Gruppo Italiano Malattie Ematologiche dell'Adulto.

PURPOSE: Recent reports of extramedullary disease (EMD) at recurrence in acute promyelocytic leukemia (APL) have raised increasing concern about a possible role of retinoic acid (RA) therapy. PATIENTS AND METHODS: We analyzed the risk of developing EMD localization at relapse in APL patients enrolled onto two consecutive studies of the Gruppo Italiano Malattie Ematologiche dell'Adulto. The studies investigated chemotherapy alone (LAP0389) versus RA plus chemotherapy (AIDA). RESULTS: When all relapse types were taken into account, 94 (51%) of 184 patients and 131 (18%) of 740 patients who attained hematologic remission underwent relapse in the LAP0389 and AIDA studies, respectively (P < .0001). EMD localization was documented in five (5%) of 94 and 16 (12%) of 131 patients (P = .08). Hematologic and/or molecular relapse was diagnosed concomitantly in all but two patients with EMD in the AIDA study. For patients in the LAP0389 and AIDA series, the probability of EMD localization of any type at relapse was 3% and 4.5%, respectively (P = .79), while the probability of CNS involvement was 0.6% and 2% (P = .28). No significant differences were found with regard to mean WBC count and promyelocytic leukemia/retinoic acid receptor-alpha junction type in comparisons of patients with EMD and hematologic relapse. CONCLUSION: APL patients receiving all-trans retinoic acid in addition to chemotherapy have no increased risk of developing EMD at relapse as compared with those treated with chemotherapy alone.

Analysis of p73 expression pattern in acute myeloid leukemias: lack of DeltaN-p73 expression is a frequent feature of acute promyelocytic leukemia.

p73, the homologue of p53, is a nuclear protein whose ectopic expression, in p53+/+ and p53-/- cells, recapitulates the most well-characterized p53 effects, such as growth arrest, apoptosis and differentiation. Unlike p53, which is mutated in half of human cancers, p73 is rarely mutated. However, altered expression of the p73 gene has been reported in neuroblastoma, lung cancer, prostate cancer and renal cell carcinoma. To investigate the potential involvement of p73 in acute myeloid leukemias (AMLs), we analyzed 71 samples from AML patients for the expression pattern of N-terminal transactivation-p73alpha (TA-p73alpha), its spliced isoforms and N-terminal-deleted-p73 transcripts (DeltaN-p73). We detected p73 gene expression in AML irrespective of FAB (French-American-British) subtypes. Notably, the analysis of DeltaN-p73 expression, which has been reported to inactivate both p53 and p73 antitumor effects, revealed a rather peculiar pattern. In fact, DeltaN-p73 transcript and protein were detectable in 27/28 (96.4%) cases of M0, M1, M2, M4, M5 and M6 AML and in 13/41 (31.7%) cases of PML-RARalpha-positive M3 AML (P<0.01). Thus, the distinct gene expression profile of p73 further supports the notion that acute promyelocytic leukemia is a biologically different subset of AML.

Interleukin 2 (IL2) in the management of acute myeloid leukemia: clinical and biological findings.

In this paper we review some of the preclinical findings which have led us to believe that immunotherapy with interleukin 2 (IL2)/lymphokine activated killer (LAK) cells may be a feasible approach in the management of acute myeloid leukemia. The main clinical and biological results so far obtained with IL2 treatment, and the currently ongoing protocols and strategies are discussed.

Autologous bone marrow transplantation followed by interleukin-2 in children with advanced leukemia: a pilot study.

In an attempt to prolong disease-free survival in children with acute leukemia, we tested the feasibility of interleukin-2 (IL-2) administration after an autologous bone marrow transplantation (ABMT). We report the clinical and biological data obtained in three children with acute myelocytic leukemia (AML) in second complete remission (CR) and in seven children with acute lymphocytic leukemia (ALL) in second or subsequent CR, who received IL-2 at a median interval of 78 days (range 38-125) from ABMT. Patients were treated with 1-2 cycles of IL-2 given by continuous infusion over a 5-day period using a daily escalating protocol, from 100 micrograms/m2 per day to the maximum tolerated dose, followed after 3 weeks by low-dose IL-2 for 5 days monthly over a 6-h infusion on an out-patient basis. Side effects greater than grade 2 (WHO system), consisting of thrombocytopenia, fever, cutaneous rash, nausea and vomiting, diarrhoea were common during the high-dose IL-2 cycles, but resolved 24-48 h after stopping IL-2. Only one patient developed liver toxicity (grade 3, WHO) on day +3 of the first cycle which prompted us to stop the administration of IL-2. An increase in lymphocytes and eosinophils was also observed. IL-2 treatment was followed by a normalization of NK function and by the generation of a high proportion of endogenous LAK cells. All seven ALL patients relapsed at a median of 5 months (range 1-23). Two AML patients relapsed at 1 and 11 months, while the other is still in continuous CR at 23 months after IL-2 treatment. Our IL-2 schedule for treatment of leukemia in children after ABMT is thus feasible but its efficacy requires further investigation.

Multiple myeloma: comparison of two dose-intensive melphalan regimens (100 vs 200 mg/m(2)).

Several trials have shown the superior impact of high-dose melphalan (usually 200 mg/m(2), MEL200) vs standard therapy in myeloma patients. Intermediate-dose melphalan (100 mg/m(2), MEL100) is also superior to the standard dose, but has not been clinically compared with MEL200. A total of 90 patients at diagnosis were treated with two MEL100 courses. Their clinical outcome was compared with that of a control group of 90 pair mates matched for serum beta2-microglobulin levels and Durie and Salmon clinical stage. These patients were treated at diagnosis with two MEL200 courses. Patient characteristics were similar in both groups except that the median age of the MEL100 group was significantly higher (P<0.0001). Complete remission was 35% after MEL100 and 48% after MEL200 (P=0.08). Median event-free survival (EFS) was 32 months in the MEL100 group and 42 months in the MEL200 group (P<0.005), but overall survival (OS) was not different. Transplant-related mortality was not significantly different. Haematological and extra-haematological toxicity was significantly reduced after MEL100. Despite the significant age difference, tandem MEL100 was less toxic than tandem MEL200, and MEL100 was inferior to MEL200 in terms of EFS but not in terms of OS. The intensified nonmyeloablative MEL100 regimen is an effective first-line treatment.

Treatment of elderly patients (> or =60 years) with newly diagnosed acute promyelocytic leukemia. Results of the Italian multicenter group GIMEMA with ATRA and idarubicin (AIDA) protocols.

In all, 134 elderly patients (median age 66 years, range 60-75 years) with newly diagnosed acute promyelocytic leukemia (APL) were enrolled in two successive protocols of the Italian multicenter group GIMEMA. All patients received an identical induction with all-trans retinoic acid and idarubicin; 116 (86%) entered complete remission (CR), two (2%) were resistant and 16 (12%) died during induction. After CR, 106 patients received further therapy whereas 10 did not, because of refusal (n=5) or toxicity (n=5). Consolidation consisted of three chemotherapy courses in the AIDA protocol (AIDA, 67 patients) or, since 1997, of an amended protocol including only the first cycle (amended AIDA, aAIDA, 39 patients). In the AIDA group, 43 patients (64%) completed consolidation, while seven (11%) and 17 (25%) patients were withdrawn after first and second courses, respectively; nine patients (13%) died in CR and 12 (18%) relapsed. In the aAIDA group, all patients received the assigned treatment; two patients (5%) died in CR and six (15%) relapsed. In the AIDA and aAIDA series, the 3-year overall and discase-free survival rates were 81 and 83% (P=NS), 73 and 72% (P=NS), respectively. We highlight here the frequency and severity of complications linked to intensive chemotherapy in this clinical setting and suggest that, in APL of the elderly, less intensive postremission therapy allows significant reduction of severe treatment-related toxicity and may be equally effective.

Acute megakaryoblastic leukemia: experience of GIMEMA trials.

The objective of the study was to evaluate the incidence, characteristics, treatment and outcome of acute megakaryoblastic leukemia (AMeL) in patients enrolled in GIMEMA trials. Between 1982 and 1999, 3603 new consecutive cases of AML aged over 15 years were admitted to GIMEMA trials. Of them, 24 were AMeL. The incidence of AMeL among AML patients enrolled in GIMEMA trials was 0.6% (24/3603). Diagnosis was based on morphological criteria. Out of 11 cytogenetic studies performed two presented chromosome 3 abnormalities. Twelve patients (50%) reached a CR, five (21%) died in induction and seven (27%) were unresponsive. The median duration of CR was 35 weeks (range 10-441). Seven patients underwent transplantation procedures (1 BMT, 4 aBMT, 2 aPBSCT). Four patients died in CR due to chemotherapy-related complications. Comparing the CR rate between AMeL and the other cases of AML enrolled in GIMEMA trials, no differences were observed. These results were mirrored for different age groups. The median survival was 40 weeks. At present, after a follow-up of a minimum of 2 years, only two patients are alive in CR, all the others having died. A 5-year Kaplan-Meier curve shows a disease-free survival of 17% and an actuarial overall survival of 10%. AMeL is a rare form of AML. The CR duration and the overall survival in this group of patients are very poor, even if similar to those observed in other AML. Furthermore, a high number of deaths in CR were observed. On the basis of these data, a specific therapeutic approach, possibly with innovative treatments, should be evaluated.

High numbers of mobilized CD34+ cells collected in AML in first remission are associated with high relapse risk irrespective of treatment with autologous peripheral blood SCT or autologous BMT.

The faster hematopoietic recovery after autologous peripheral blood SCT (APBSCT) in patients with AML may be offset by an increased relapse risk as compared with autologous BMT (ABMT). The EORTC and GIMEMA Leukemia Groups conducted a trial (AML-10) in which they compared, as second randomization, APBSCT and ABMT in first CR patients without an HLA compatible donor. A total of 292 patients were randomized. The 5-year DFS rate was 41% in the APBSCT arm and 46% in the ABMT arm with a hazard ratio (HR) of 1.17; 95% confidence interval=0.85-1.59; P=0.34. The 5-year cumulative relapse incidence was 56% vs 49% (P=0.26), and the 5-year OS 50% and 55% (P=0.6) in the APBSCT and ABMT groups, respectively. APBSCT was associated with significantly faster recovery of neutrophils and platelets, shorter duration of hospitalization, reduced need of transfusion packed RBC and less days of intravenous antibiotics. In both treatment groups, higher numbers of mobilized CD34+ cells were associated with a significantly higher relapse risk irrespective of the treatment given after the mobilization. Randomization between APBSCT and ABMT did not result in significantly different outcomes in terms of DFS, OS and relapse incidence.

Autologous bone marrow transplantation in children with acute myeloblastic leukemia: report from the Italian National Pediatric Registry (AIEOP-BMT).

This report summarizes indications and results of autologous bone marrow transplantation (ABMT) performed in childhood acute myeloid leukemia (AML) in Italy since 1984. A total of 158 patients have been reported from 12 teams to the AIEOP-BMT Registry: 110 have been autografted in first complete remission (CR) and 48 in second remission. Several conditioning regimens have been utilized, mainly consisting of BAVC (an original polichemotherapy schedule, BCNU, mAMSA, VP-16 and Ara-C) (63 cases) and of total body irradiation (TBI) plus Melphalan (33 cases): other 28 patients received different TBI-including regimens, and 34 received various chemotherapy regimens (Busulfan plus cyclophosphamide +/- VP-16, Busulfan plus Melphalan, Melphalan alone). Projected event-free survival (EFS) for patients autografted in first CR is 41.4% (S.E. 5.5%) at 7 years, with a total of 53 patients in continuous CR. EFS is better in patients receiving a TBI-including regimen: 78.8% versus 27.2% (p = 0.0001). In particular, results obtained in a subgroup of 21 cases receiving TBI + melphalan and purged marrow are particularly encouraging, with a EFS > 85% projected a 7 years. The overall EFS in second CR is 41.5% at 7 years, and no difference have been observed after a TBI-including regimen or after a chemotherapy regimen, being EFS 43.1% and 39.3% for these 2 groups respectively. A total of 11 transplant-related deaths occurred, with 5 patients (4.5%) dead in first CR and 6 (12%) dead in second CR within 100 days from transplant. From these data, ABMT is confirmed to represent an effective treatment for AML after first relapse, while the encouraging results obtained in first CR with TBI-including regimens should be confirmed with a longer follow up and a larger number of patients.

BAVC regimen and autograft for acute myelogenous leukemia in second complete remission.

Since 1984 we have autografted a total of 60 patients with AML in second complete remission (CR) utilizing the BAVC (BCNU, amsacrine, vepesid, cytosine-arabinoside) conditioning regimen and unpurged marrow. Projected disease-free survival (DFS) probability in 42% at 10 years. Autografting was performed at a median interval of 2 months (range 1-13) from second CR. The median duration of first CR was 14 months (range 1-43) and lasted < or = 12 months in 27/60 patients. Three early deaths (5%) occurred, 30 patients relapsed after a median of 6 months from transplant (range 2-28) and, of the remaining 27 patients, 26 are in continuous CR (CCR) after a median follow up of 60 months (range 6-122), while the last patient committed suicide 7 years after ABMT when she was still in CCR. A first CR duration > 12 months is correlated with a significantly better overall survival probability (61 vs 25%, P = 0.02), while no factors influence DFS. Outcome of patients who relapsed after autografting has been analyzed separately; a longer overall survival after relapse is correlated with a longer duration of the second CR (62% at 34 months for patients who relapsed after > 12 months from the autograft vs 5% for the others, P = 0.001). These results confirm that AML patients autografted in second CR with BAVC regimen and unpurged marrow have the possibility of becoming long-term DFS and can therefore be cured.

ABMT for children AML: Italian experience. GITMO-AIEOP Groups.

We report data from an Italian survey on ABMT in 93 AML children less than 14 years in 1st or 2nd remission performed in 15 Centers. Different conditioning regimens have been employed: BAVC, an original schedule of chemotherapy; TBI plus Cy and/or other drugs (TBI + CHT); other high dose chemotherapy schedules (HD CHT). 62 patients have been transplanted in 1st CR; 38 have been conditioned with BAVC, 16 with TBI + CHT and 8 with HD CHT. Relapses were 21 in the BAVC group (DFS = 35% at 66 months), 5 in the TBI group (DFS = 61% at 48 months) and 5 in the HD CHT group; overall DFS is 39% at 66 months. 31 patients have been transplanted in 2nd CR; 14 were conditioned with BAVC and 16 with TBI + CHT; 6 patients relapsed in the first group, DFS is 56% at 50 months; in the second group 2 early deaths and 3 relapses occurred, DFS is 65% at 65 months. 1 patient in 2nd CR, conditioned with HD CHT, died during aplasia. Overall DFS is 59% at 65 months. Although no final conclusions concerning ABMT in AML children may be drawn from this retrospective study because of heterogeneity of population and methods, results obtained in 2nd CR are clearly better to those obtained with standard chemotherapy alone, confirming the role of ABMT in this high risk category of patients.

Autologous bone marrow or peripheral blood stem cell transplantation for patients with chronic myelogenous leukaemia in chronic phase.

The progressive and fatal course of chronic myelogenous leukemia has not been affected significantly by chemotherapeutic agents that control the benign phase of the disease. Combination chemotherapy and aggressive treatments may offer some advantages: however, these approaches do not appear to produce stable suppression of Ph1 chromosome or to prolong chronic phase and survival of these patients. Only allogeneic bone marrow transplantation has been demonstrated to be capable of inducing a stable, complete suppression of Ph1+ cells. Recently alpha Interferons (IFN) have been shown to control myeloid proliferation in patients with CML and to determine a progressive and persistent decline of Ph1+ bone marrow cells in some cases. The hypothesis that in most newly diagnosed patients with CML various amount of Ph1 negative cells must still be present, albeit in suppressed state in the bone marrow (BM) or in the peripheral blood (PB), have led some Authors to treat patients with high-dose chemotherapy followed by reinfusion of stem cells collected at diagnosis or after a response to cytoreductive treatments. We report 34 patients with CML treated in chronic phase with Busulohan and Melphalan conditioning regimen followed by reinfusion of BM or PB stem cells.

Effect of chemotherapy for acute myelogenous leukemia on hematopoietic and fibroblast marrow progenitors.

Since reduced marrow cellularity and prolonged pancytopenia following autologous bone marrow transplantation (ABMT) have been frequently observed in patients with acute myelogenous leukemia (AML) included in the AML10 GIMEMA/EORTC trial, the question was raised to what extent hematopoietic and microenvironmental progenitor cells were involved in these patients. Marrow hematopoietic progenitors were investigated by a short-term methylcellulose assay quantitating multipotent CFU-Mix, erythroid BFU-E and granulocyte-macrophage CFU-GM, as well as a long-term assay quantitating long-term culture-initiating cells (LTC-IC). The marrow microenvironment was studied by evaluating the incidence of fibroblastoid progenitors (CFU-F) and the capacity of stromal layers to support allogeneic hematopoietic progenitors. As compared to normal controls (n = 57), AML patients (n = 26) showed a statistically significant reduction of the mean (+/-s.e.m.) number of CFU-Mix (5.3 +/- 0.6 vs 0.8 +/- 0.2, P < or = 0.0001), BFU-E (68 +/- 5 vs 20 +/- 4, P < or = 0.0001), CFU-GM (198 +/- 11 vs 144 +/- 15, P < or = 0.008), and LTC-IC (302 +/- 46 vs 50 +/- 8, P < or = 0.001). The mean (+/-s.e.m.) incidence of marrow CFU-F was not significantly reduced as compared to normal controls (48 +/- 6 vs 52 +/- 7, P < or = 0.73). Seventeen AML stromal layers were tested for their capacity to support the growth of allogeneic hematopoietic progenitors. Seven samples failed to support any progenitor cell growth, seven had a significantly lower supportive activity as compared to normal stromal layers (13 +/- 5 vs 249 +/- 56, P < or = 0.002), whereas three cultures could not be analyzed due to contamination. In conclusion, induction and consolidation regimens used in AML patients of the AML10 protocol induce a markedly defective in vitro growth of primitive hematopoietic progenitors and a severe functional defect of marrow stroma. The association of hematopoietic with microenvironmental damage might play a key role in the delayed hematopoietic regeneration observed following ABMT in patients of the AML10 trial.

Obesity and autologous stem cell transplantation in acute myeloid leukemia.

In the bone marrow transplant setting, several authors hypothesized that severely overweight patients are at increased risk of transplant-related toxicity, but different definitions of obesity, different body weight groupings and heterogeneous samples of patients were analyzed. To overcome these limitations, we retrospectively considered a homogeneous group of 54 patients (median age 36.5 years), with a diagnosis of de novo acute myeloid leukemia (AML), autografted in first complete remission (CR) with the Bu-Cy2 conditioning regimen, dosed on actual body weight. Patients were classified into three groups (obese, non-obese, underweight) using body mass index (BMI = kg/m(2)); for each group we analyzed transplant-related toxicity and mortality, overall survival and disease-free survival (OS/DFS). In spite of the relatively small number of patients, in our results high BMI appears a predictive factor for an increase of treatment-related toxicity and mortality. Moreover, 30 (55%) patients are currently alive in continuous CR, and after a median follow-up of 76.5 months (range 14-137) statistically significant differences in OS and DFS were detected between obese and non-obese groups (P = 0.012 and 0.021, respectively). Our study suggests that obesity may represent an independent risk factor for autograft in AML and further investigations are warranted.