Level of minimal residual disease after consolidation therapy predicts outcome in acute myeloid leukemia

We used flow cytometry to quantify minimal residual disease (MRD) in 56 patients with acute myeloid leukemia (AML) expressing a leukemia-associated phenotype. Thirty-four patients aged 18 to 60 years were entered into the AML-10 protocol (induction, consolidation, and autologous stem-cell transplantation [ASCT]), whereas 22 patients older than 60 years received the AML-13 protocol (induction, consolidation, and consolidation II). After induction, the level of MRD that was best associated with treatment outcome was 4.5 x 10(-4) residual leukemic cells. However, the outcome in patients with at least 4.5 x 10(-4) cells (n = 26) was not significantly different from that in patients with fewer leukemic cells (n = 30); there were 15 (58%) relapses in the first group and 12 (40%) relapses in the second. After consolidation, the most predictive MRD cutoff value was 3.5 x 10(-4) cells: 22 patients had an MRD level of 3.5 x 10(-4) cells or higher and 17 (77%) of these patients had relapse, compared with 5 of 29 patients (17%) with lower MRD levels (P <.001). An MRD level of 3.5 x 10(-4) cells or higher after consolidation was significantly correlated with poor or intermediate-risk cytogenetic findings, a multidrug resistance 1 (MDR1) phenotype, short duration of overall survival, and short duration of relapse-free survival (P =.014,.031,.00022, and.00014, respectively). In multivariate analysis, this MRD status was significantly associated with a high frequency of relapse (P <.001) and a short duration of overall (P =.025) and relapse-free survival (P =.007). ASCT did not alter the prognostic effect of high MRD levels after consolidation: the relapse rate after transplantation was 70%. Thus, we found that an MRD level of 3.5 x 10(-4) cells or higher at the end of consolidation strongly predicts relapse and is significantly associated with an MDR1 phenotype and intermediate or unfavorable cytogenetic findings. (Blood. 2000;96:3948-3952)

Pulsed intravenous high-dose dexamethasone in adults with chronic idiopathic thrombocytopenic purpura

The role of pulsed high-dose dexamethasone (DXM) in the treatment of patients with chronic idiopathic thrombocytopenic purpura (ITP) is still uncertain. Following an early report in which it was described as an effective and well-tolerated treatment with a sustained platelet response in 100% of cases, a number of subsequent studies have failed to confirm such favorable results. As all these studies were conducted on small numbers of patients, we investigated further the effectiveness and side effects of this therapeutic modality in a larger cohort. Thirty-two patients with chronic ITP were scheduled to receive six monthly courses of intravenous DXM at the dose of 40 mg/day for 4 consecutive days. All patients had ITP that had been resistant to between two and five different therapeutic regimens, including 9 patients who had already failed splenectomy. All patients had to be seen 2 weeks after each cycle to asses their response as well as secondary effects. Three patients failed to respond and clinically required other therapy. Thirteen patients (41%) had a partial (platelet count between 50 and 100 x 10(9)/liter) or complete (platelet count >100 x 10(9)/liter) response to treatment, responses being mostly transient. Responses were observed early during the course of treatment, usually right after the first cycle of DXM. There were no late responses. Side effects were mild and did not require discontinuation of treatment. No clinical or laboratory parameter was found to predict treatment outcome. We conclude that high-dose DXM has a limited effect in patients with chronic ITP. Novel approaches and controlled multicenter trials may help identify new therapeutic strategies for this disease.

Effect of house dust mite avoidance measures in children with atopic dermatitis

BACKGROUND

House dust mite allergens are associated with atopic dermatitis (AD).

OBJECTIVES

The aim of our study was to verify if house dust mite allergen avoidance measures can improve the clinical manifestations of AD in children.

METHODS

Forty-one children (mean age 3.9 years) affected by AD associated with high total and/or specific IgE serum levels ('extrinsic' AD) were recruited. Clinical evaluation was performed utilizing the Severity Scoring of AD (SCORAD) index; dust was sampled from the children's beds and tested using an enzyme-linked immunosorbent assay. The study was planned in two parts. In the first part, a placebo-controlled trial of 2 months duration, mite allergen avoidance measures (encasing mattresses and pillows; a weekly hot wash of bedding; frequent vacuum cleaning of living room and bedroom; soft toys and carpets regularly cleaned or removed; no pets allowed) were recommended to group A patients, but not to group B. In the second part of the study, environmental avoidance measures were recommended to initial control group B patients also. One year after the start of the study the amounts of mite allergen in the home and clinical score of AD were measured in both groups.

RESULTS

At the end of the first part of the study, significant decreases in major allergens of Dermatophagoides pteronyssinus (Der p1) and D. farinae (Der f1) load (from 393 to 94 ng m-2) and concentration (from 1.84 to 0.73 microg g-1 of dust) in children's beds were observed in treatment group A. At the same time, in this group the mean SCORAD index improved significantly (from 33 to 26; P = 0.022). After 12 months, when all patients had used allergen avoidance measures, Der p1 + Der f1 load, concentration and clinical score had improved, reaching similar values in both groups.

CONCLUSIONS

Simple mite allergen avoidance measures should be recommended to families with children affected by extrinsic AD in order to control the clinical manifestations and prevent mite sensitization.

The natural history of sensitizations to food and aeroallergens in atopic dermatitis: a 4-year follow-Up

The natural history of atopic dermatitis (AD) is variable. Generally the dermatitis disappears during the first years of life, but it is often followed by the appearance of allergic respiratory diseases (ARDs). Our aim was to establish the risk factors for developing an ARD in children with AD. We followed up for 4 years 78 children (51 boys, 27 girls) with mild (26%), moderate (48%), and severe (26%) AD (clinical score proposed by Rajka and Langeland). In all the patients IgE serum levels were checked and skin prick tests (SPTs) were performed at the first examination. The SPTs were repeated in 68 children at the end of the study. The children with severe AD had significantly higher IgE serum levels than those with mild or moderate AD. SPTs at the first observation were positive in 47% of cases, mostly in patients with severe AD, with a prevalence of food allergens, particularly in younger patients. At the second observation, SPTs were positive in 65% of cases, including 100% of children with severe AD. Inhalants were the most common allergens. An ARD appeared in 38% of all patients: in 75% of those with severe AD and in 54% of those with a positive first SPT. Allergic screening should be carried out at an early age, especially in severe AD, since SPT positivity to food allergens, associated with severe clinical AD symptoms and a high IgE serum level, identifies those children ages 0-3 years at high risk of development of ARD.

A novel t(11;12)(q23-24;q24) in a case of minimally-differentiated acute myeloid leukemia (AML-M0)

Acute myeloid leukemia with minimal signs of myeloid differentiation (AML-M0) is a recent addition to the FAB group classification. Chromosome data is scarce, but existing reports describe a high incidence of complex karyotypes and myelodysplastic syndrome-like chromosome alterations, while single chromosome translocations have rarely been reported. We describe the case of a 60-year-old woman diagnosed with AML-M0 with a novel translocation t(11;12)(q23-24;q24) as the sole karyotypic marker. Fluorescence in situ hybridization analysis to assess MLL gene splitting did not show rearrangement of this oncogene.

A phase-II trial of all trans retinoic acid and low-dose cytosine arabinoside for the treatment of high-risk myelodysplastic syndromes

Twenty-two patients with high-risk myelodysplastic syndrome (HRMDS) were treated with a 10-day course of oral all trans retinoic acid (45 mg/m2) and s.c. low-dose cytosine arabinoside (LDARAc) given at the dose of 20 mg twice per day. The courses were repeated monthly until response or progression, in the case of response, the therapy was administered until relapse. Morphologic diagnoses were refractory anemia with excess blasts (RAEB) in nine, RAEB in transformation (RAEB-t) in nine, and chronic myelomonocytic leukemia (CMMoL) in four patients; in all cases, bone-marrow blast infiltration was greater than 10% (median 20%, range 12-30%). When the international prognostic scoring system was applied, all the cases qualified as intermediate/high-risk categories. Nineteen patients were males and three were females; the median age was 69 years (range 25-90 years); three patients had previously been treated with conventional chemotherapy, and one of them had also undergone autologous bone-marrow transplantation. The criteria of response were defined as follows: (1) complete response: normalization of blood counts and bone-marrow blasts (<5%), and (2) partial response: decrease in bone-marrow blast infiltration by 50%, and two of the following parameters - improvement in hemoglobin level by 1.5 g/dl or decrease by 50% in transfusional requirement, increase by 50% in absolute neutrophil count, and increase by 50% in platelet count. Overall, 7 (32%) of 22 patients achieved a response, with 5 (23%) being classified as complete responders and 2 (9%) as partial responders. Fifteen (68%) patients did not achieve any response, and 14 died of progressive disease or infectious disease. The overall median survival was 8 months (range 1-27 months), whereas the median survival of responders was 16 months (range 8-27 months); the median duration of response was 11 months (range 2-21 months). Moderate to severe hematological toxicity and infections were the most common side effects. In conclusion, it seems that the association of ATRA and LDARA-C may be effective in approximately 30% of HRMDS patients. Optimizing this approach might be pursued by selecting, on a biological basis, those cases more likely to respond or by incorporating other differentiating agents or growth factors.

Latex allergy in subjects who had undergone multiple surgical procedures for bladder exstrophy: relationship with clinical intervention and atopic diseases

OBJECTIVE

To evaluate the prevalence of latex sensitization in a group of patients with bladder exstrophy, and to determine the role of associated risk factors, e.g. atopy, and the number and duration of surgical and anaesthetic procedures.

PATIENTS AND METHODS

The study comprised 17 patients (15 children and two young adults) affected by bladder exstrophy who had undergone multiple surgical procedures. Skin-prick tests and specific immunoglobulin-E (IgE) assays against latex, food allergens cross-reacting with latex and inhalant allergens were carried out.

RESULTS

Twelve patients showed latex sensitization and five showed symptoms related to latex exposure, the most common of which was contact urticaria (four of the symptomatic patients). Intraoperative anaphylactic reaction had led to life-threatening events in only one child. Latex-specific IgE determined both by the prick test and assay was positive in all those with symptoms. Specific IgEs against inhalant allergens and foods were present in four of five symptomatic patients. In the seven sensitized patients with no clinical symptoms, the assay was positive in all, while the skin-prick test was positive only in four; specific IgEs against inhalant allergens were present in three of the seven. In the five patients not allergic and not latex-sensitized, only one showed allergic sensitization against grass pollen and mite allergen. None of the children without latex antibodies had symptoms of latex allergy. Symptomatic patients had a undergone significantly more hours of surgery, more cystography and had used intermittent catheterization for longer than those with no symptoms.

CONCLUSION

A third of patients with bladder exstrophy showed latex symptoms and another third had latex sensitization. Multiple surgical procedures and atopy play a major role in the development of latex hypersensitivity

Systemic interferon-alpha treatment for idiopathic Sweet's syndrome

Despite the various therapeutic strategies used in the treatment of acute febrile neutrophilic dermatoses, interferon-alpha has so far been proposed only as an intralesional monotherapy for cutaneous lesions and has only had partial success. We now describe the treatment of a long-standing, previously drug resistant, case of idiopathic Sweet's syndrome. After an initial successful combined short therapy with systemic interferon-alpha and hydroxyurea, the results were maintained by long-term treatment with interferon-alpha only. To our knowledge, this is the first report showing a clear response to the drug in a patient affected by Sweet's syndrome.

Femoral catheters: safety and efficacy in peripheral blood stem cell collection

Central venous access is necessary in patients candidate for peripheral blood stem cell (PBSC) collection. We report our experience with a dual lumen femoral catheter (Gamcath, 11 french), initially designed for hemodialysis. We studied 147 patients and performed 488 collections after mobilization with either G-CSF alone or chemotherapy + G-CSF, when the white blood cell count exceeded 1 x 10(9)/L, or when a measurable population of CD34+ cells (20/microL) was detected in peripheral blood. All patients received systemic anticoagulation with a low weight heparin and ultrasound examination was performed after the removal of the catheter. Seven patients developed thrombosis (4.7%), ten experienced hematomas at the site of catheter placement (6.8%) despite prophylactic platelet transfusions, while only one patient (0.6%) had a catheter-related infection. In conclusion, the short-term use of large bore femoral catheters in setting up PBSC collection seems to be associated with minimal risk of infection and low thrombotic incidence.

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.

Mite allergen (Der p 1) levels in houses of children with atopic dermatitis: the relationship with allergometric tests

Several studies, in particular in adult groups, have evaluated the involvement of mites in the pathogenesis of atopic dermatitis (AD). This still remains controversial. The objective of this study was to determine the level of house dust mites (HDMs) in the beds of a group of children with AD and correlate these levels with their allergometric assessment. Forty-one children with AD underwent allergometric tests (prick test, patch test and radioallergosorbent test, RAST) and the concentration levels of HDMs in their homes were evaluated. Our data show that about half of the children (51%) with AD presented Dermatophagoides pteronyssinus positivity (prick test and/or RAST and/or patch test). Dust was collected in the period October-November from the children's beds, by the same two operators, using a dust-collection device. The dust mite level was tested by an enzyme-linked immunosorbent assay with antibody against Der p 1 allergen. Ten children (24%) presented a Der p 1 concentration > 2 microgram/g of dust (the value assumed to be a risk level for sensitization), 20 (49%) between 0.1 and 2 microgram/g and 11 (27%) < 0.1 microgram/g of dust. In the group with the highest Der p 1 concentration (> 2 microgram/g dust) nine children (90%) presented an allergometric D. pteronyssinus sensitivity, the difference with the other two groups being statistically significant at P < 0.018. The results of the present study show that the highest HDM concentrations were observed in the group with an allergometric D. pteronyssinus positivity (prick test and/or RAST and/or patch test). It is hypothesized that a higher HDM concentration may elicit D. pteronyssinus IgE sensitization and delayed hypersensitivity in children with AD.

A comparative analysis of FISH, RT-PCR, and cytogenetics for the diagnosis of bcr-abl-positive leukemias

Philadelphia (Ph) chromosome-positive leukemias, with the bcr-abl gene translocation, have a dismal prognosis. The identification of Ph-positive patients is vitally important because only aggressive therapeutic approaches, such as allogeneic bone marrow transplantation, may result in long-term disease-free survival. Routine diagnostic methods, such as Southern blot analysis and cytogenetics, may lead to false-negative results. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis is considered the most sensitive tool for the detection of the bcr-abl translocation, and it is widely used alone or in combination with karyotyping or Southern blot analysis to identify Ph-positive cases. In this study, we used fluorescence in situ hybridization (FISH) with BCR and ABL double-color probes for detecting Ph-positive leukemias. The FISH results were compared with the results of cytogenetic and RT-PCR analyses in 75 patients with leukemia or other myeloproliferative syndromes (chronic myeloid leukemia, 30; acute lymphoblastic leukemia, 24; acute myelogenous leukemia, 6; essential (hemorrhagic) thrombocythemia, 12; chronic myelomonocytic leukemia, 2; and polycythemia vera, 1). FISH analysis proved to be simple, extremely reliable and sensitive; bcr-abl fusion detection was successful in the presence of all types of molecular junctions i.e., (b2a2, b3a2, and e1a2). Furthermore, a Ph-positive case that proved fusion negative by RT-PCR was identified as positive by FISH. The sensitivity of RT-PCR and FISH related to Ph-positive cases were 97% and 100%, respectively. Regarding specificity, in 4 (5%) of 75 patients, RT-PCR provided false-positive results. Cross-contamination was identified because a new specimen was harvested and reanalyzed when FISH, cytogenetics, and RT-PCR results were contradictory. We believe FISH is an optimal diagnostic method to detect bcr-abl translocation that can be used alone or to validate the results of RT-PCR analysis.

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.

Minimally differentiated acute myeloid leukemia (AML-M0): comparison of 25 cases with other French-American-British subtypes

We compared the immunophenotypic and karyotypic features of 25 cases of minimally differentiated acute myeloid leukemia (AML-M0) with those of 247 cases comprising all AML French-American-British (FAB) classification. Myeloperoxidase (MPO) was detectable with a specific monoclonal antibody in all cases of AML-M0, whereas CD13 and CD33 were both negative in 4 of the 25 cases. Thus, anti-MPO reliably detects minimal myeloid differentiation in AML-M0. CD34 and terminal deoxynucleotidyl transferase (TdT) were more frequently expressed in AML-M0 (96% and 68% of the cases, respectively) than in the other FAB subsets (P < .001 for both). By contrast, GP-170 and CD7 were less frequently expressed in AML-M0 than in FAB classes such as M1, M4, and M5 (P = .02 and .003, respectively). A total of 80% of AML-M0 cases carried lymphoid markers (including TdT), and 48% showed a coordinate positivity for two or more of them. CD2, CD5, CD10, and CD19 were expressed in a similar fashion among the different FAB groups, whereas CD4 expression was significantly more frequent in AML-M0, AML-M4, and AML-M5 (P = .014). AML-M0 was characterized by a more frequent occurrence of complex karyotypes. In addition, approximately 20% of cases had TdT positivity, complex karyotypes, and anomalies of chromosome 5 and/or 7, a pattern not observed in the other FAB subsets. Finally, 80% of anomalies of chromosome 5 and/or 7 in AML-M0 were comprised within complex karyotypes, whereas only 13% of the remaining FAB cases carried this feature. In summary, AML-M0 frequently expresses immunophenotypic and karyotypic aspects that are likely to identify a "stem cell" pattern.

FISH analysis for CML monitoring?

Conventional cytogenetics is considered the gold standard for evaluating CML during interferon (IFN) treatment. Drawbacks to this approach are the small number of metaphases available during IFN therapy and the impossibility of scoring interphase cells. We applied, besides cytogenetics, double-color FISH (dc-FISH) detection of BCR-ABL gene fusion to monitor 20 CML patients on IFN. dc-FISH easily detected 200 cells per specimen, while with cytogenetic examination a mean of 16.1 mitoses per sample were scored. Though the correlation of dc-FISH and cytogenetic data was good (r = 0.77, p < 0.001), the discrepancy between the two methods as regards the proportion of leukemic cells in the marrow was often important dc-FISH detected a relevant proportion of BCR-ABL+ cells in three patients classified as complete cytogenetic responders and showed that, after 9-12 months of IFN treatment, a significant reduction of BCR-ABL+ cells was present in all the 20 patients tested. This might suggest that all CML patients are potentially responsive to IFN. Though more data are required, we think that dc-FISH is more informative than cytogenetic analysis for CML monitoring. Notably because of the simplicity of the procedure, this method could be easily standardized among different laboratories, thus permitting cross-comparison in therapeutic trials.