Minimal residual disease negativity in elderly patients with acute myeloid leukemia may indicate different postremission strategies than in younger patients.

In the present analysis, we evaluated whether in elderly acute myeloid leukemia (AML) patients (>60 years), minimal residual disease (MRD) assessed by flow cytometry may have a role in guiding choice of postremission strategies. We analyzed 149 young and 61 elderly adults who achieved morphological CR after induction course of EORTC/GIMEMA protocols. Elderly patients reached a postconsolidation MRD negative status less frequently than younger ones (11 vs 28 %, p = 0.009). MRD negativity resulted in a longer 5-year disease-free survival (DFS) both in elderly (57 vs 13 %, p = 0.0197) and in younger patients (56 vs 31 %, p = 0.0017). Accordingly, 5-year cumulative incidence of relapse (CIR) of both elderly (83 vs 42 %, p = 0.045) and younger patients (59 vs 24 % p = NS) who were MRD positive doubled that of MRD negative ones. Nevertheless, CIR of MRD negative elderly patients was twofold higher than that of younger MRD negative ones (42 vs 24 %, p = NS). In conclusion, elderly patients in whom chemotherapy yields a MRD negative CR have duration of DFS and rate of CIR significantly better than those who remain MRD positive. Nonetheless, the high CIR rate observed in the elderly suggests that MRD negativity might have different therapeutic implications in this population than in the younger counterpart.

Mini-extracorporeal circulation minimizes coagulation abnormalities and ameliorates pulmonary outcome in coronary artery bypass grafting surgery.

Hemostasis is impaired during CABG and coagulation abnormalities often result in clinically relevant organ dysfunctions, eventually increasing morbidity and mortality rates. Fifteen consecutive patients with coronary artery disease submitted to conventional extracorporeal circulation (cECC) have been compared with 15 matched patients, using mini-ECC (MECC). Postoperative lung function was evaluated according to gas exchange, intubation time and lung injury score. In the MECC group, thrombin-antithrombin complex levels (TaTc), prothrombin fragments (PF1+2) formation and thromboelastography (TEG) clotting times were lower compared to the cECC group (p=0.002 and p<0.001, respectively) whereas postoperative blood loss was higher in the cECC group (p=0.030) and more patients required blood transfusion (p=0.020). In the MECC group, postoperative gas exchange values were better, intubation time shorter and lung injury score lower (p<0.001 for all comparisons). Our study suggests that MECC induces less coagulation disorders, leading to lower postoperative blood loss and better postoperative lung function. This approach may be advantageous in high-risk patients.

Comparison between azacitidine and decitabine as front-line therapy in elderly acute myeloid leukemia patients not eligible for intensive chemotherapy.

We compared the efficacy of azacitidine (AZA) and decitabine (DEC) in elderly patients with untreated AML, diagnosed according to WHO criteria. In the two groups, we evaluated complete remission (CR), overall survival (OS) and disease free survival (DFS). The AZA and DEC groups included 139 and 186 patients, respectively. To minimize the effects of treatment selection bias, adjustments were made using the propensity-score matching method, which yielded 136 patient pairs. In the AZA and DEC cohort, median age was 75 years in both, (IQR, 71-78 and 71-77), median WBCc at treatment onset 2.5 × 109/L (IQR, 1.6-5.8) and 2.9 × 109/L (IQR, 1.5-8.1), median bone marrow (BM) blast count 30% (IQR, 24-41%) and 49% (IQR, 30-67%), 59 (43%) and 63 (46%) patients had a secondary AML, respectively. Karyotype was evaluable in 115 and 120 patients: 80 (59%) and 87 (64%) had intermediate-risk, 35 (26%) and 33 (24%) an adverse risk karyotype, respectively. Median number of cycles delivered was 6 (IQR, 3.0-11.0) and 4 (IQR, 2.0-9.0), CR rate was 24% vs 29%, median OS and 2-year OS rates 11.3 (95% CI 9.5-13.8) vs 12.0 (95% CI 7.1-16.5) months and 20% vs 24%, respectively. No differences in CR and OS were found within the following subgroup: intermediate- and adverse-risk cytogenetic, frequency of WBCc at treatment ≥ 5 × 10^9 L and < 5 × 10^9/L, de novo and secondary AML, BM blast count < and ≥ 30%. Median DFS for AZA and DEC treated patients was 9.2 vs 12 months, respectively. Our analysis indicates similar outcomes with AZA compared to DEC.

The emerging role of measurable residual disease detection in AML in morphologic remission.

Despite the increasing knowledge of the genomic landscape of acute myeloid leukemia (AML), prediction merely based on genetics fails to anticipate outcome, presumably due to the heterogeneous composition of the leukemic clone determining complex interactions between different genetic abnormalities. Therefore, the introduction of a post-treatment biomarker exploring the quality of response to therapy such as assessment of measurable (previously minimal) residual disease (MRD) may lead to refinements of the prognostic assessment in AML. In this view, the European LeukemiaNet has recently endorsed the achievement of a MRD negative morphologic complete remission as a purpose the treatment. Techniques like multiparametric flow cytometry and reverse transcriptase-quantitative polymerase chain reaction have reached a level of sensitivity and specificity that make them ready for introduction in clinical practice. In the present review, we will give an update on the efforts in harmonization and/or standardization of MRD assessment in AML, focusing on the newest acquisitions in the clinical applications of MRD, and considering issues like relationship of MRD with leukemic stem cells or MRD assessment in peripheral blood.

The kinetics of reduction of minimal residual disease impacts on duration of response and survival of patients with acute myeloid leukemia.

UNLABELLED: We assessed by multiparametric flow cytometry the levels of minimal residual disease (MRD) in 100 adult patients with acute myelogenous leukemia (AML) achieving complete remission after intensive chemotherapy. The aim of the study was to determine the optimal threshold, in terms of residual leukemic cells, and the time point of choice, that is, post-induction (post-Ind) or post-consolidation (post-Cons), able to better predict outcome. By applying the maximally selected log-rank statistics, the threshold discriminating MRD- from MRD+ cases was set at 3.5 x 10(-4) residual leukemic cells, a level that allowed the identification of distinct subgroups of patients, both at post-Ind and post-Cons time points. Post-Cons MRD- patients had a superior outcome in terms of relapse rate, overall survival (OS) and relapse-free survival (RFS) (P<0.001, for all comparisons), regardless of the MRD status after induction. In particular, patients entering MRD negativity only after consolidation showed the same outcome as those achieving early negativity after induction. Multivariate analysis, including karyotype, age, MDR1 phenotype, post-Ind and post-Cons MRD levels, indicated that the post-Cons MRD status independently affected relapse rate, OS and RFS (P<0.001, for all comparisons). IN CONCLUSION: (1) the threshold of 3.5 x 10(-4) is valid in discriminating risk categories in adult AML and (2) post-Cons MRD assessment is critical to predict disease outcome.

Simultaneous detection of NPM1 and FLT3-ITD mutations by capillary electrophoresis in acute myeloid leukemia.

Mutations in the Nucleophosmin (NPM1) gene have been recently described to occur in about one-third of acute myeloid leukemias (AML) and represent the most frequent genetic alteration currently known in this subset. These mutations generate an elongated NPM1 protein that localizes aberrantly in the cytoplasm. In analogy with Flt3 alterations, NPM1 mutations are mostly detectable in AML with normal karyotype and their recognition may be relevant to identify distinct response to treatment. Hence, in addition to conventional karyotyping and RT-PCR of fusion genes, combined analysis of both Flt3 and NPM1 mutations will be increasingly relevant in the genetic diagnosis work-up of AML. We developed a multiplex RT-PCR assay followed by capillary electrophoresis to simultaneously analyze NPM1 and Flt3 gene alterations (NFmPCR assay). The assay was validated in leukemic cell RNAs extracted from 38 AML patients, which had been previously characterized for Flt3 status by conventional RT-PCR. Direct sequencing of NPM1 RT-PCR products was carried out in 15 cases to verify results obtained by capillary electrophoresis. Both NPM1 sequencing and conventional RT-PCR Flt3 results showed 100% concordance with the results of the NFmPCR assay. We suggest that this assay may be introduced in routine analysis of genetic alterations in AML.

Venetoclax: Bcl-2 inhibition for the treatment of chronic lymphocytic leukemia.

Venetoclax (ABT-199) is a small-molecule selective oral inhibitor of the antiapoptotic protein Bcl-2 that promotes programmed cell death of chronic lymphocytic leukemia (CLL) cells regulating the release of proapoptotic factors, such as Smac/Diablo, apoptosis-inducing factor (AIF) and cytochrome c. In April 2016, the U.S. Food and Drug Administration (FDA) granted accelerated approval to venetoclax for patients diagnosed with CLL with 17p deletion, as detected by an FDA-approved test, who have received at least one prior therapy. This review will focus on the mechanism of action, preclinical studies and clinical development of venetoclax both as a monotherapy and in combination with other drugs for CLL in the current milieu of therapy dominated by novel tyrosine kinase inhibitors such as ibrutinib and idelalisib.

All-trans retinoic acid and low-dose cytosine arabinoside for the treatment of 'poor prognosis' acute myeloid leukemia.

Thirty-three patients with 'poor prognosis' acute myeloid leukemia, no longer suitable for aggressive chemotherapy, were treated with daily oral all-trans retinoic acid (45 mg/m2) daily and subcutaneous cytosine arabinoside (20 mg standard dose twice a day, day 1 to 10, every 4 weeks). Seventeen patients were males and 16 females, the median age was 67 (range 39-82 years). Eleven patients were at onset of disease, 15 were refractory to previous conventional therapies, three were in first relapse and three in second relapse and one patient had a secondary AML. Seventeen patients had a bone marrow blast infiltration < 50% and 16 > or = 50%. A total of 16 (48%) patients entered complete remission; the rate of complete remission increased to 88% in those patients (n = 17) with < 50% blast infiltration at the time of entering the study. Seventeen patients (52%) were resistant. The difference in response to therapy, according to bone marrow blast percentage (< or > or = 50%), was statistically significant (P < 0.001). Median duration of complete remission was 34.4 weeks (range 6.4-62.8). Mild to moderate hematologic toxicity was the most common side-effect. In conclusion all-trans retinoic acid and low-dose cytosine arabinoside appears to be an effective regimen for inducing complete remission in 'poor prognosis' acute myeloid leukemia and patients with < 50% bone marrow infiltration are likely to represent the ideal target to receive this combination therapy.

Pretransplant minimal residual disease level predicts clinical outcome in patients with acute myeloid leukemia receiving high-dose chemotherapy and autologous stem cell transplantation.

A total of 31 adult patients with AML entered in the EORTC/GIMEMA AML-10 trial, who received autologous stem cell transplantation (ASCT) after induction and consolidation chemotherapy, were prospectively evaluated for minimal residual disease (MRD) by multidimensional flow cytometry (MFC). Using a cutoff level of 3.5 x 10(-4) leukemic cells pre-ASCT, 12 patients (39%) were stratified to MRD high-risk group and 19 (61%) into MRD low-risk group. During follow-up, all patients who were in the high-risk group relapsed at a median time of 7 months; in the low-risk group, five patients relapsed at a median time of 11 months and 14 remained in remission for 56 (range 7-80) months (P=0.00004). Longitudinal MFC determinations post-ASCT showed increased MRD levels in three of the five patients who underwent subsequent relapse, while disease recurrence was unpredicted in the remaining two cases. The pre-ASCT MRD status was the factor most strongly associated with relapse risk in the multivariate analysis (P=0.0014). We conclude that: (1) pre-ASCT MRD status predicts successful outcome in patients receiving ASCT; (2) high-dose chemotherapy conditioning regimen followed by ASCT has no impact on the unfavorable prognostic value of high pre-ASCT MRD level; and (3) sequential MRD monitoring post-ASCT may allow the prediction of impending relapse.

Prognostic relevance of the expression of Tdt and CD7 in 335 cases of acute myeloid leukemia.

We have analyzed the expression of Tdt and CD7 in 335 cases of unequivocal acute myeloid leukemia (AML). Tdt was expressed in 80 (25%) of 321 evaluable cases. Twenty-six of 77 (34%) Tdt+ patients assessable for response, entered complete remission (CR) vs 121 of 209 (58%) Tdt- cases (P < 0.001). CD7 was expressed in 102 of 332 (30%) evaluable cases; 37 of 93 assessable (40%) CD7+ patients attained a CR as compared to 114/204 (56%) CD7- (P = 0.013). Duration of survival was significantly shorter for patients with CD7+ or Tdt+ AML (P = 0.006 and 0.001, respectively). In a multivariate analysis, Tdt was found to significantly adverse achievement of CR (P = 0.018), while CD7 affected duration of CR (P = 0.037). Overall the expression of either Tdt or CD7 correlated with a relatively high expression of CD34 (P < 0.001), GP-170 (P = 0.003), lymphoid antigens (LyAg) (P < 0.001), t(9;22) or anomalies of chromosome 5/7 (P < 0.001). Finally, we pooled the patients into four phenotypic classes, according to the presence of Tdt, CD7 or both: [Tdt-CD7-], [Tdt+CD7-], [Tdt-CD7+] and [Tdt+CD7+]. The category [Tdt+CD7+] was characterized by a more unfavorable outcome as suggested by a lower rate of CR (P < 0.001) and a shorter duration of survival as compared to cases [Tdt-CD7-], [Tdt+CD7-] and [Tdt-CD7+] (P = 0.002). This figure is consistent with the frequent convergence in the subset [Tdt+CD7+] of GP-170 positivity (P = 0.003), translocation t(9;22), anomalies of chromosome 5 and/or 7 (P < 0.001) and signs of lineage infidelity (deviant expression of lymphoid antigens) (P < 0.001). We conclude that the expression of Tdt or CD7 is associated with an unfavorable outcome and that the combination of both defines a clinical subset with a poorer prognosis due to the significantly higher association with MDR phenotype, and 'poor prognostic' chromosomal abnormalities.

Accuracy of physician assessment of treatment preferences and health status in elderly patients with higher-risk myelodysplastic syndromes.

Higher-risk myelodysplastic syndromes (MDS) are rarely curable and have a poor prognosis. We investigated the accuracy of physicians' perception of patients' health status and the patients' preferences for involvement in treatment decisions. We examined 280 newly diagnosed higher-risk elderly MDS patients paired with their physicians. Survey tools included the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) and the Control Preference Scale. Overall concordance was 49% for physician perception of patient preferences for involvement in treatment decisions. In 36.4% of comparisons there were minor differences and in 14.6% there were major differences. In 44.7% of the patients preferring a passive role, physicians perceived them as preferring an active or collaborative role. Absence of the patient's request for prognostic information (P=0.001) and judging the patient as having a poor health status (P=0.036) were factors independently associated with the physicians' attitude toward a lower degree of patient involvement in clinical decisions. Agreement on health status was found in 27.5% of cases. Physicians most frequently tended to overestimate health status of patients who reported low-level health status. The value of decision aid-tools in the challenging setting of higher-risk MDS should be investigated to further promote patient-centered care.

P-glycoprotein and terminal transferase expression identify prognostic subsets within cytogenetic risk classes in acute myeloid leukemia.

Clinical and biological features were assessed in 204 consecutive de novo adult acute myeloid leukemia (AML) patients who received intensive chemotherapy regimens. Multiparameter flow cytometric assays both of the multidrug resistance (MDR-1)-associated P-glycoprotein (PGP) using the UIC2 monoclonal antibody (MoAb), and of terminal transferase (TdT) were performed. Cytogenetic findings were obtained from 196 patients with high resolution banding. At onset, UIC2 and TdT positivities were detected in 58.5% and 24% of cases, respectively. There were strict correlations either between UIC2 negativity and FAB M3 or between TdT and FAB M0-M1 (P = 0.001 and < 0.0001, respectively). On the other hand, age was significantly associated with cytogenetic risk classes (P < 0.0001). CD34 positivity was highly correlated with TdT expression (P < 0.0001). Moreover, CD7 and CD11b were significantly represented in UIC2+ subset (P < 0.0001). Rhodamine 123 (Rh 123) efflux was significantly higher in 75 UIC2 positive patients compared to 65 UIC2 negative ones (P < 0.001). As regards to cytogenetics, TdT positivity was strongly related either to t(9;22) or single/associated anomalies of chromosome 7; on the other hand, most or all cases with t(8;21) or t(15;17) were UIC2 or TdT negative, respectively. The rate of first complete remission (CR) differed both between UIC2+ and UIC2- cases and between TdT+ and TdT- ones (40% versus 72%, P < 0.001; and 36% versus 61%, P = 0.001, respectively). The survival rates (Kaplan-Meier method) were significantly shorter either in UIC2+ or in TdT+ patients (P = 0.005 and = 0.011, respectively). UIC2 and TdT negative cases showed longer remission duration (P = 0.03 and = 0.22, respectively). The additional effect of UIC2 and TdT on prognosis allowed us to identify two subsets of patients, the first [UIC2- TdT-] at better and the second [UIC2+ TdT+] at worse clinical outcome compared to single UIC2 and TdT cases, concerning CR (P < 0.001), survival (P < 0.0001) and CR duration (P = 0.007). The combinations [UIC2+ TdT-] and [UIC2- TdT+] showed an intermediate clinical course. A strong difference was found between poor risk and intermediate/favorable risk cytogenetic classes with regard to CR rate (P < 0.0001), overall survival and CR duration (P < 0.001). Nevertheless, within the poor risk class, UIC2 positivity was able to identify patients at worst prognosis with regard to CR (P = 0.005), survival (P = 0.02) and CR duration (P = 0.015). On the other hand, UIC2 and TdT negativity allowed us to distinguish patients with longer survival (P = 0.012 and = 0.04, respectively) and CR duration (P = 0.04 and = 0.025, respectively) within the intermediate/favorable risk class. The independent prognostic value of UIC2, TdT and cytogenetic risk classes was confirmed in multivariate analysis. These results suggest that PGP and TdT expressions, together with cytogenetic findings, may represent a basic predictor of chemotherapeutic failure in AML.

Modulation of VLA-4 and L-selectin expression on normal CD34+ cells during mobilization with G-CSF.

We have evaluated the immunophenotype, functional activity and clonogenic potential of CD34+ cells from peripheral blood (PB) of normal donors before and after 4 and 6 days of G-CSF administration. The percentage and absolute number of CD34+ cells significantly increased at days 4 and 6 of G-CSF administration, compared to the steady-state level (P < 0.0001). Two-colour fluorescence analysis showed, at days 4 and 6, a lower proportion of CD34+/c-kit+ compared to the steady-state level (P < 0.0001), but a similar expression of CD13, CD33, CD38, HLA-DR and Thy-1 antigens on CD34+ cells. The expression of adhesion molecules on CD34+ cells revealed a significant reduction of CD11a (P = 0.009), CD18, CD49d and CD62L (P < 0.0001) at days 4 and 6, compared to the baseline level. Three-colour staining showed a reduction of the more immature compartment (34+/DR-/13-) and an increase of the more differentiated compartment (34+/DR+/13+). Downregulation of VLA-4 during mobilisation was seen almost exclusively on more committed cells (34+/13+); downregulation of CD62L, on the contrary, was observed on both early progenitors (34+/13-) and more committed cells (34+/13+). The expression of 34+/VLA-4+ decreased on both c-kit+ and c-kit- cells, while the expression of 34+/62L+ decreased on the c-kit+ cells only. In vivo administration of G-CSF reduced the adherence capacity of CD34+ cells to normal BM stroma; in vitro incubation with SCF or IL-3 enhanced the expression of CD49d on CD34+ cells, while GM-CSF reduced the expression of CD62L. SCF was the only cytokine able to induce a significant increase of CD34+ cell adherence to preformed stroma. Pre-incubation with the blocking beta2 integrin monoclonal antibody caused a reduction of CD34+ cell adherence. In conclusion, the decrease of CD49d expression on mobilized CD34+ cells correlates with a poor adhesion to BM stroma; CD34+ cells incubated in vitro with SCF showed, conversely, a higher expression of CD49d and a greater adherence capacity on normal preformed stroma.

Enumeration of CD34+ hematopoietic progenitor cells for clinical transplantation: comparison of three different methods.

Three different methods for determination of CD34+ cells in G-CSF-mobilized peripheral blood were compared. The methods were: the Milan/Mulhouse protocol, the ISHAGE guidelines for CD34+ cells enumeration and our own protocol. The procedure we have adopted is essentially a Milan/Mulhouse protocol-derived methodology combined with a multiparametric approach using the PAINT-A-GATE software analysis program. The samples were collected from 70 patients affected by acute leukemia, non-Hodgkin's lymphoma, Hodgkin's lymphoma, myeloma and breast cancer who were scheduled to receive autologous PBSC transplantation. PBSC collection was performed following mobilization with subcutaneous G-CSF at 5-10 microg/kg/day. A minimum target of 2 x 10(6)/kg CD34+ cells was considered an acceptable harvest to ensure a safe transplant. On average, three aphereses per patient were performed and a total of 204 apheresis samples were analyzed. Regression analysis of the percentage and absolute number of CD34+ cells, as calculated with each method, achieved an excellent correlation in spite of methodological differences. In fact, both CD34+dim and CD34+CD45- events were included in our gating strategy. In the setting of a triple staining associating CD34, CD38 and CD45, we identified a variable fraction of CD34+CD38+CD45- cells which would be otherwise undetected due to its CD45 negativity. To this end, we used a new technology referred to as laser-scanning cytometry (LSC) which allowed the isolation and morphological identification of CD34+CD45- cells. By comparing CD34+CD45+ and CD34+CD45- cells, we found that they share a common morphology, thus confirming the hypothesis that the latter are to be considered for CD34+ cell calculation. The median number of CD34+ cells/kg, as calculated by the three methods, was: 4.79 x 10(6)/kg (range 1-570) for the Milan/Mulhouse protocol, 3.9 x 10(6)/kg (range 0.8-498) for the ISHAGE one, and 5.17 x 10(6)/kg (range 2-599) for our protocol. The median time to ANC and PLT engraftment was 11 (range 9-24) and 20 (range 10-70) days, respectively. Our protocol achieved the best correlation between CD34+ cells/kg and time to ANC/PLT recovery according to the Spearman's rank test (r = -40 and P < 0. 015 for ANC, r= -46 and P = 0.005 for PLT). We conclude that (1) CD45 does not appear the ideal partner of HPCA-2 for determination of hematopoietic progenitors in mobilized peripheral blood; and (2) for clinical application, a single staining with 8G12 appears simple, reliable and feasible when rigorous procedures for sample preparation and acquisition are followed and an adequate software for multiparametric analysis is available.

CD7 expression in acute myeloid leukemia.

The clinical significance of the expression of CD7 antigen on the blasts of 207 consecutive patients with de novo acute myeloid leukemia (AML) was evaluated. For this purpose, fifty-three CD7+ patients (23 females and 30 males; mean age 52 years) were analyzed and classified into the following subtypes according to French-American-British (FAB) classification: 7 M0, 13 M1, 9 M2, 1 M3, 9 M4, 14 M5. Immunophenotypic studies were carried out by flow cytometry and blast cells were selected on the basis of forward light scatter gating and pan-myeloid marker, either CD13 or CD33. All the CD7+ patients were negative for surface CD3 and T-cell-receptor (TCR) molecules. We found no correlation between CD7 expression and sex, age, hepatosplenomegaly and/or central nervous system involvement. The immaturity of CD7+ leukemic cells was supported by the high expression of CD34 (P = 0.001). CD7 positivity was significantly associated with a white blood cell count (WBC) greater than 100 x 10(9)/L (P = 0.003). P-Glycoprotein (P-170) expression was also evaluated in 135 patients by a flow-cytometric assay: there was a close relationship between CD7 and P-170 positivity (P < 0.001). For remission induction, all patients received therapeutic regimens routinely used for AML. The complete remission (CR) rate was significantly lower in CD7+ cases (32% vs 74%, P = 0.001). The overall survival and disease free survival rate of CD7+ AML was lower than those of CD7- patients (P < 0.001 and = 0.002, respectively). CD7+ AML with coexpression of CD14 had a particularly unfavourable response and prognosis in comparison with CD7+ patients without CD14.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant interferon alpha 2a, thymopentin and low doses of cytosine arabinoside for the treatment of myelodysplastic syndromes: a pilot study.

Eighteen patients (pts) with myelodysplastic syndrome (MDS) were treated with thymopentin (TP) (50 mg subcutaneously for 5 days) and recombinant interferon alpha 2a (rIFN alpha 2a) (3 MU/m2 subcutaneously on the sixth day); the courses were delivered every week. Moreover those pts with > or = 10% blasts in the bone marrow were additionally treated with low dose cytosine arabinoside (LDARAc) (20 mg standard dose, subcutaneously, twice a day for seven days every four weeks). Sixteen pts were finally assessable for response. Seven pts (44%) were classified as good responders, 5 (31%) had a PR; the overall response rate (GR+PR) was 75%. Two pts (12.5%) showed stable disease and the 2 remaining (12.5%) had progressive disease. Six pts with an initial moderate anemia never required supportive care before and during the therapy; in contrast to 10 pts who were transfusion-dependent. After six months of therapy 2 pts decreased their transfusional needs by 50% (1 of them did not receive any transfusion over the following six months of therapy); 2 pts needed no packed red cell infusions and 1 pt decreased his transfusional support by 75%. Five pts kept an unchanged supportive care load. The overall median survival was 12.5 months. Therapy was generally well tolerated with acceptable compliance; the most frequently recorded side effects were neutropenia and thrombocytopenia grade 2-3 among the group receiving LDARAc. However no life-threatening infectious episodes or bleeding were observed. TP, rIFN alpha 2a and LDARAc can be safely administered on an outpatient basis to MDS pts and appears to have significant activity.(ABSTRACT TRUNCATED AT 250 WORDS)

P-glycoprotein expression in de novo acute myeloid leukemia.

Detection of the multidrug resistance P-glycoprotein (PGP) phenotype was performed at the time of diagnosis in 223 patients with acute myeloid leukemia (AML) by flow cytometry using C219 Monoclonal Antibody (MoAb). On the other hand, JSB1 MoAb was tested in 173 of these samples. At onset, PGP was detected in 57.4% of cases with C219 and 75.9% of cases with JSB1. There was no correlation between PGP expression and sex, age, marrow blast percentage or extramedullary disease. On the contrary, strict correlations were noted either between C219 negativity and FAB M3 subtype or between C219 positivity and FAB M5 group (P = 0.003). Significant correlation was found between PGP phenotype and CD7, as 143 of 223 samples had similar patterns of staining with C219 (P < 0.0001). Finally, there was a close relationship between C219 and JSB1 positivity: all the C219+ cases were positive for JSB1 (P < 0.0001). Concerning the karyotype, most patients with monosomy or del (7) were MDR positive; on the other hand, most patients with t(8;21) or t(15;17) were MDR negative. Rh123 accumulation studies showed a significant decrease of mean fluorescence intensities both in C219 and in JSB1 positive cases in comparison with PGP negative ones (P < 0.001). A significant decrease of remission induction rates (CR) was highlighted both between C219+ and C219- and between JSB1+ and JSB1- cases (32.1% v 62.1% and 32.6% v 73.8%, respectively, with P < 0.0001). The overall survival and the remission duration (CCR) were significantly shorter both in C219+ and in JSB1+ patients with no relationship to age. Furthermore, a higher rate of early relapses was noted among MDR+ when compared with MDR- patients both for C219+ and JSB1+ cases. The combination (C219- JSB1+) identified a subset of patients with an intermediate prognosis. On multivariate analysis, C219 and JSB1 were confirmed to be independent prognostic factors for achievement of CR, overall survival and CCR. In conclusion, the assessment of MDR phenotype by flow cytometry is a crucial prognostic factor of treatment outcome in AML.

Multiparametric analysis for the enumeration of CD34+ cells from bone marrow and stimulated peripheral blood.

Determination of CD34+ cells was performed in bone marrow and G-CSF mobilised peripheral blood samples. We adopted three different protocols of analysis: the Milan/Mulhouse protocol, the ISHAGE guidelines for CD34+ cell determination and our own protocol based upon the use of PAINT-A-GATEPRO software analysis program. An excellent correlation was demonstrated between the three methods (r2 0.98); however the analysis of variance showed a statistically significant difference between the results generated with the three methods (P=0.001). The differences between the three procedures are discussed with a special focus on the value of CD34+dim cells and the role of CD45 in the setting of a double staining. We have in fact identified a minor subset (CD34+CD38+CD45-) which would go unrecognised based upon its CD45 negativity.