T(1;7) in Acute Myeloblastic Leukemia following Myelodysplastic Syndrome (RAEB-T)

A case is described of myelodysplastic syndrome (MDS) refractory anemia type with an excess of blasts in transformation with early leukemic evolution (AML-M1). All bone marrow cells examined showed an unbalanced translocation t(1;7). The karyotype was 45, xy, –21, –7, + der dic t(1;7) (q12;q21). There are reports in the literature of the translocation t(l;7) (pll;pll), which leads to trisomy of the long arms of chromosome # 1 and monosomy of the long arms of chromosome # 7. In the case here described the breakpoints of the chromosomes involved in the translocation differ from the classic ones: in this case there is trisomy of the region 1q12→1qter and monosomy of the region 7q21→7qter. Some clinical and cytogenetic considerations are suggested.

Association of -318 C/T and +49 A/G cytotoxic T lymphocyte antigen-4 (CTLA-4) gene polymorphisms with a clinical subset of Italian patients with systemic sclerosis

Systemic sclerosis (SSc) is a complex and heterogeneous autoimmune disorder with a multi-factorial pathogenesis. Like other autoimmune disorders, the possible role of specific cytotoxic T lymphocyte antigen-4 (CTLA-4) gene polymorphisms in predisposing to SSc has been hypothesized, but it remains controversial. CTLA-4 promoter (-318C/T) and exon 1 (+49 A/G) polymorphisms have been analysed in 43 Italian females with SSc and in 93 unrelated matched healthy controls by a newly designed tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) method. No significant association has been found with either polymorphisms.Nevertheless, SSc patients without concomitant Hashimoto's thyroiditis (HT) were carrying both the -318T allele (P = 0.031) and the +49 G allele (P = 0.076) more frequently than SSc patients with HT [defined by positivity for anti-thyroperoxidase (TPO) and anti-thyroglobulin (TGA) autoantibodies] than controls. Haplotype analysis confirms this association (P = 0.028), and suggests the predominant role of the -318T, whereas that of the +49 G, if any, seems weak. Thus, in Italian SSc patients the CTLA-4 -318C/T promoter polymorphism appears to be associated with the susceptibility to develop SSc without thyroid involvement. Larger studies are needed to confirm these findings and to clarify whether the -318C/T polymorphism is the functional responsible or whether it reflects the presence of another linked genetic element in the same chromosomal region.

AIRE gene polymorphisms in systemic sclerosis associated with autoimmune thyroiditis

Mutations in the autoimmune regulator (AIRE) gene are responsible for autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED). Systemic sclerosis (SSc) is a non-organ-specific autoimmune disease mainly characterized by cutaneous involvement, that is frequently associated with other autoimmune manifestations common to APECED. Nineteen SSc patients, 22 patients affected by SSc associated with autoimmune thyroiditis, and 100 healthy controls were analyzed. We identified 11 AIRE gene variants, one of which has never previously been described. Intronic polymorphism G11107A was significantly correlated to SSc/thyroiditis. Data show that variants of the AIRE gene might be correlated to different clinical manifestations in SSc patients.

Monitoring molecular response by BCR-ABL, JH and WT-1 in Ph+ all treated with imatinib containing regimen: preliminary report of two cases

We carried out sequential molecular monitoring of different markers on two BCR-ABL positive ALL patients receiving a standard dose induction regimen, which was followed by a maintenance therapy that alternated imatinib and chemotherapy administration. Molecular study was performed at diagnosis, at the end of the induction phase, and then every three months during maintenance therapy. Each marrow sample underwent BCR-ABL analysis (p210 and p190 expression by RT-PCR and Real-time PCR) and monoclonal JH rearrangement analysis, while WT1 gene expression was detected by Real-time PCR. At diagnosis we detected high WT1 expression associated with the presence of both BCR-ABL transcripts and monoclonal JH rearrangement in both patients. Hematological remission, as well as a molecular status characterized by undetectable BCR-ABL expression, normal levels of WT1 expression, and persistence of monoclonal JH rearrangement, were achieved by both patients post-therapy. Follow up of patient 1 showed a progressive increase in WT-1 and in p-190 transcript, which was followed by cytogenetic and hematological relapse. We observed a progressive increase in the p210 transcript without a concomitant increase in WT-1 levels in patient 2. JH rearrangement was detected in all the samples analyzed. The molecular results may indicate the persistence of JH rearranged clonal cells with undetectable BCR-ABL. From a clinical point of view, our preliminary experience suggests that simultaneous analysis of BCR-ABL, JH and WT-1 expression may improve the study of MRD in Ph+ ALL.

Cytogenetic and fluorescence in situ hybridization monitoring in Ph+ Chronic Myeloid Leukemia patients treated with imatinib mesylate

Imatinib mesylate determines a favorable clinical course in most Ph positive Chronic Myeloid Leukemia (CML) patients in the chronic phase. Cytogenetic response is usually evaluated by analyzing 20-25 bone marrow metaphases using standard banding techniques. Since this methodology has very low sensitivity, we compared the results obtained by standard banding techniques to the ones obtained by fluorescent in situ hybridization (FISH). This was also done to identify any possible discrepancies between the two techniques. We analyzed 40 Ph+ CML patients in the chronic phase who had previously been treated with interferon alpha (IFNalpha) and who were receiving imatinib. The studies were performed by utilizing the same BM cell samples fixed in acetic acid/methanol, before imatinib therapy and then quarterly. Comparison of cytogenetic results to FISH results at 3 and 6 months of imatinib treatment showed that some patients who had achieved major cytogenetic response (i.e.<35% of examined metaphases showing Ph), showed retention of a higher number of persisting Ph+ cells when examined by FISH, and they did not achieve major FISH response (i.e. <35% of examined interphase cells show the BCR-ABL fusion signal). The discrepancy we found between the results that were obtained by analyzing metaphases and interphase cells disappeared in the subsequent examinations. Moreover, we found that 4 patients (10%) were still Ph+ in all the metaphases we examined even though they achieved excellent clinical response. On the basis of this small series of patients, we suggest that cytogenetic evaluation of patients on imatinib therapy should be performed by utilizing the classic banding technique (metaphase examination), but also by using the FISH technique (interphase examination), since the two methodologies may provide different results.

Fludarabine, ARA-C, idarubicin and G-CSF (FLAG-Ida), high dose ARA-C and early stem cell transplant. A feasable and effective therapeutic strategy for de novo AML patients

Forty-three consecutive patients with de novo and untreated non M3 AML aged 60 or less entered the study. The mean age of patients was 50 (range 15-60). The induction regimen (FLAG-Ida) included fludarabine (30 mg/sqm), Ara-C (2 g/sqm) on days 1-5, and idarubicin (10 mg/sqm) on days 1, 3, 5. G-CSF (300 mcg/day) was administered s.c. 12 hours before starting fludarabine and was continued for five days. HDT with stem cell rescue was planned for all patients in first CR after one course of high dose Ara-C (HDAC) consolidation and in good clinical conditions. Forty-two (98%) patients were evaluable for response. One patient died during induction (2%). CR was achieved in 35 patients (82%). Twenty-three patients, 66% of those achieving CR, underwent autologous (N = 17) or allogeneic (N = 6) transplantation. With a median follow up of 24 months, the average median duration of CR is 17 months (range 3-66) and the median survival is 20 months (range 1-83). Overall the 5 year projected disease free survival (DFS) and overall survival (OS) were 37% and 43%, respectively. Among patients who underwent stem cell transplantation DFS and OS were 53% and 69%, respectively. The median time to PMN recovery (> 0.5 x 10(9)/l) was 17 days (range 10-28) and 50 x 10(9)/l platelets were reached at a median of 17 days (12-38). In conclusion FLAG-Ida regimen is effective, low toxic and improves feasibility of stem cell transplant.

Allogeneic bone marrow transplantation (BMT) for adults with acute lymphoblastic leukemia (ALL): predictive role of minimal residual disease monitoring on relapse

We developed a PCR-based method to monitor clonogenic IgH VDJ rearrangement as a possible predictor of relapse in patients with acute B-ALL after allogeneic bone marrow transplantation (BMT). We studied 23 patients at diagnosis, before and after BMT. At the time of BMT, 13 patients were in first complete remission, eight in second complete remission and two in relapse. Four patients were PCR negative before BMT and remained PCR negative also after BMT (-/- pattern). They are still in remission after a median follow-up of 41 months. Nineteen patients were MRD-positive before BMT: three were PCR negative at first determination after BMT (+/- pattern) and maintain remission. Sixteen patients were PCR-positive at first determination after BMT (+/+ pattern): five became PCR negative (+/+/- pattern) (four with chronic graft-versus-host disease (GVHD) and two after donor lymphocyte infusions (DLI)). Nine patients remained PCR-positive (+/+/+ pattern) (four remain in remission, and six relapsed); two patients died before transplant. In conclusion, PCR negative patients before BMT remained negative post-BMT; many pre-BMT positive patients had initial MRD positivity after BMT: 37% of them achieved a molecular remission with cGVHD or DLI.

Interferon-alpha protects Philadelphia-negative progenitors from exhaustion in chronic myeloid leukemia patients with cytogenetic response

INTRODUCTION

Normal immature hematopoietic progenitors are relatively well preserved in most patients newly diagnosed with chronic myeloid leukemia, but tend to decline rapidly with time. Such exhaustion could reflect a suppressive effect of the Philadelphia positive clone expansion and/or be induced by Interferon-alpha treatment.

MATERIALS AND METHODS

A total of 51 CML patients were classified into three groups. Newly diagnosed untreated patients were group A (n=30). Of the 21 treated individuals with Interferon-alpha, for at least 12 months, 15 showed no cytogenetic response (group B) while six showed persisting major/complete response (group C). Patients belonging to groups A and B were mobilized with chemotherapy plus G-CSF while patients of group C received a short course of G-CSF only.

RESULTS

Patients responding to IFN-alpha (group C) showed comparable numbers of bone marrow Ph- long-term culture initiating cells to those of newly diagnosed individuals (group A): 8.5 (<1-65)/10(6) MNC vs 10.5 (<1-30), while non-responders had markedly lower numbers: <1 (<1-5). The amount of Ph- LTC-IC collected was significantly lower in patients of group B 1.8 (0-325)x10(2)/kg than in patients of either group A 31.3 (0-952)x10(2)/kg (P<0.002) or group C 109 (8-259)x10(2)/kg (P<0.01). Interestingly, five patients of group B who had 100% Ph+ metaphases, but Ph- progenitors in their bone marrow, mobilized normal amounts of Ph(-) progenitors.

CONCLUSION

These findings suggest that the decline of normal hematopoietic progenitors, currently observed in the majority of CML patients, is not induced by IFN-alpha treatment, but it is likely due to the expanding leukemic clone. They also indicate that normal hematopoietic reservoir is consistently preserved in patients given IFN-alpha early after diagnosis and achieving a stable cytogenetic response.

The prognostic value of cytogenetics is reinforced by the kind of induction/consolidation therapy in influencing the outcome of acute myeloid leukemia--analysis of 848 patients

We studied the impact of cytogenetics and kind of induction/consolidation therapy on 848 adult acute myeloid leukemia (AML) patients (age 15-83). The patients received three types of induction/consolidation regimen: standard (daunorubicin and cytosine arabinoside (3/7); two cycles); intensive (idarubicin, cytosine arabinoside and etoposide (ICE), plus mitoxantrone and intermediate-dose Ara-C (NOVIA)); and low-dose (low-dose cytosine arabinoside). CR patients under 60 years of age, if an HLA-identical donor was available received allogeneic stem cell transplantation (allo-SCT); otherwise, as part of the program, they underwent autologous (auto)-SCT. CR rates significantly associated with 'favorable' (inv(16), t(8;21)), 'intermediate' ('no abnormality', abn(11q23), +8, del(7q)) and 'unfavorable' (del (5q), -7, abn(3)(q21q26), t(6;9), 'complex' (more than three unrelated cytogenetic abnormalities)) karyotypes (88% vs 65% vs 36%, respectively; P = 0.0001). These trends were confirmed in all age groups. On therapeutic grounds, intensive induction did not determine significant increases of CR rates in any of the considered groups, with respect to standard induction. Low-dose induction was associated with significantly lower CR rates. Considering disease-free survival (DFS), multivariate analysis of the factors examined (including karyotype grouping) showed that only age > 60 years significantly affected outcome. However, in cases where intensive induction was adopted, 'favorable' karyotype was significantly related to longer DFS (P = 0.04). This was mainly due to the favorable outcome of t(8;21) patients treated with intensive induction. Patients receiving allo-SCT had significantly longer DFS (P = 0.005); in particular, allo-SCT significantly improved DFS in the 'favorable' and 'intermediate' groups (P = 0.04 and P = 0.048, respectively). In conclusion our study could provide some guidelines for AML therapy: (1) patients in the 'favorable' karyotype group seem to have a longer DFS when treated with an intensive induction/consolidation regimen, adopted before auto-SCT instead of standard induction; this underlines the importance of reinforcement of chemotherapy, not necessarily based on repeated high-dose AraC cycles. Allo-SCT, independently of induction/consolidation therapy, should be considered an alternative treatment; (2) patients in the 'intermediate' karyotype group should receive allo-SCT; (3) patients in the 'unfavorable' karyotype group should be treated using investigational chemotherapy, considering that even allo-SCT cannot provide a significantly longer DFS, but only a trend to a better prognosis.

First line therapy with fludarabine combinations in 42 patients with either post myelodysplastic syndrome or therapy related acute myeloid leukaemia

Acute myeloid leukaemias (AML) evolving from a myelodysplastic syndrome (MDS) or secondary to chemoradiotherapy frequently display unfavorable biologic characteristics. This may explain the lower remission rate obtained with conventional chemotherapy. Recently, the association of Fludarabine with intermediate dose Ara-C has produced interesting results particularly in high risk AML patients. Here, we report on 42 secondary AML patients treated with a combination of Fludarabine, intermediate dose Ara-C, G-CSF with or without an antracycline (FLANG, FLAG-IDA or FLAG). Overall, complete remissions (CR) were documented in 14 patients (33%) and partial responses (PR) in 12 (29%), while 10 patients proved resistant (24%). Six patients (14%) died early. The presence of a prognostically unfavorable karyotype had a negative impact on the CR rate (20% compared to 50% for patients with an intermediate prognosis karyotype, p 0.05). Patients treated with FLAG, FLANG and FLAG-IDA had similar CR rates. At the time of this analysis, after a mean follow-up of 12 months, the mean duration of CR is 16 months (range 3-66) and the mean survival is 11 months (range 1-67). The median time to granulocyte recovery (neutrophils > 0.5 x 10(9)/l) was 20 days (range 12-39) and 50 x 10(9)/l platelets were reached at a median of 26 days (range 9-56). Taken together, these Fludarabine containing regimens proved to be an effective and tolerable treatment for patients with secondary AML. Patients above 70 years of age may also benefit from this therapy, however the problem of treating patients with adverse chromosomal abnormalities still remains unresolved.

Alternative donor transplants for patients with advanced hematologic malignancies, conditioned with thiotepa, cyclophosphamide and antithymocyte globulin

Preparative regimens without total body irradiation (TBI) have been reported for alternative donor hemopoietic stem cell transplants (HSCT). Between 7 September 1994 and 7 June 1999 48 patients with advanced hematologic malignancies were conditioned with thiotepa (THIO) 15 mg/kg, cyclophosphamide (CY) 150 mg/kg and antithymocyte globulin (ATG). Donors were HLA mismatched family members (1-2 antigens) (FAM) (n = 24, median age 31 years) or HLA matched unrelated donors (UD) (n = 24, median age 34 years). GVHD prophylaxis was cyclosporine and methotrexate. Stem cell source was peripheral blood (n = 8) or bone marrow (n = 40). Hematologic recovery was seen in 42/46 (91%) evaluable patients and complete chimerism in 31/37 patients (85%). Acute GVHD grades III-IV were seen in 10/46 patients surviving 10 days (21%) and extensive chronic GVHD in 2/36 patients surviving 100 days (5%). Twenty-six patients died (54%), eight of recurrent disease (17%) and 18 of transplant-related complications (37%): main causes of TRM were GVHD (15%), infections (15%) and graft failure (4%). Twenty-two patients (46%) survive with a median follow-up of 877 days (287-1840). The actuarial 3-year survival is 49% for FAM and 42% for UD transplants. Results obtained with this regimen in unrelated grafts for advanced CML (n = 15) were not significantly different when compared to 21 concurrent UD grafts for advanced CML prepared with CY-TBI. In conclusion, the combination of THIO-CY-ATG allows engraftment of alternative donor hemopoietic stem cells. Results are similar when using unrelated matched donors or partially mismatched family donors, and not significantly different when compared to patients conditioned with CY-TBI.

High-dose chemotherapy with tandem autologous transplantation as part of the initial therapy for aggressive non-Hodgkin's lymphoma

The purpose of the present study was to evaluate the feasibility and the efficacy of employing a high-dose chemotherapy (HDT) regimen with tandem peripheral blood progenitor cells (PBPC) supported transplantation in the initial treatment of aggressive non-Hodgkin's lymphoma (NHL). HDT was preceded by a standard course of conventional dose chemotherapy in 17 out of the 25 patients treated, while in 8 cases it was delivered after only one or two cycles. HDT was a three-step procedure which included high-dose (6-7 g/m2) cyclophosphamide (CY) supported by haematopoietic growth factors, the first myeloablative course with mitoxantrone (NOV) 60, 75 or 90 mg/m2 plus melphalan (L-PAM) 140-180 mg/m2 with haematopoietic rescue, and the second myeloablative course with etoposide (VP) and carboplatin (CARBO) given at 1.5 g/m2 each with haematopoietic rescue. PBPC were collected after CY administration. Twenty-two patients (88%) completed the HDT, haematological reconstitution was rapid and complete at each step and there were no toxic deaths. The activity of the treatment was high with a CR rate over 90% in the entire patient population. The 2-year overall survival (OS) and failure-free survival (FFS) rates of patients in both Age-Adjusted International Prognostic Index (A-AIPI) groups 2 and 3 are 79% and the disease-free survival (DFS) rate for the CRs is 85%. In A-AIPI group 1 the 2-year OS and FFS rates are both 91%.

Reduced intensity thiotepa-cyclophosphamide conditioning for allogeneic haemopoietic stem cell transplants (HSCT) in patients up to 60 years of age

Transplant-related mortality (TRM) remains a major problem in older patients undergoing allogeneic haemopoietic stem cell transplants (HSCTs). We have therefore explored a less intensive conditioning in 33 patients with a median age of 52 years (range 43-60) transplanted from human leucocyte antigen (HLA)-identical siblings. The underlying disease was chronic myeloid leukaemia (n = 15), acute myeloid leukaemia (n = 6), myelodysplasia (n = 7) or a chronic lymphoproliferative disorder (n = 5); 15 patients (45%) had advanced disease. The regimen consisted of thiotepa (THIO; 10 mg/kg) on day -5 and cyclophosphamide (CY; 50 mg/kg) on days -3 and -2 (total dose 100 mg/kg). The source was bone marrow (BM) (n = 17) or granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood (PB) (n = 16), which were infused without manipulation. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin A (CyA) and a short course of methotrexate. Mean time to achieve a neutrophil count of 0.5 x 109/l was 17 d (range 11-23) and full donor chimaerism was detected in 79% of patients by day 100. Acute GVHD grade III or IV occurred in 3% of patients. Chronic GVHD was seen in 45% of patients, with a significant difference for PB (69%) compared with BM transplants (23%) (P = 0.009). For BM grafts, the actuarial 2-year TRM was 6%, the relapse 56% and survival 87%; for PB grafts, these figures were, respectively, 27%, 33% and 68%. Twenty-five patients are alive at a median follow-up of 762 d (range 216-1615) and 20 patients (60%) remain free of disease. Thirteen patients (39%) received donor lymphocyte infusion (DLI) either for persisting or relapsing disease and six patients had complete remission.

IN CONCLUSION

(i) patients up to the age of 60 years can be allografted with reduced intensity conditioning; (ii) the procedure was associated with a low transplant-related mortality, particularly for bone marrow grafts, because of a lower risk of chronic GVHD; and (iii) DLI were required after transplant in half the patients for persisting disease or relapse.

Effects of three cytokine regimens on hematologic recovery and progenitor cell mobilization after high-dose cyclophosphamide, etoposide, and cisplatin

The aim of this study was to compare both the effects on hematologic recovery and circulating progenitor cell mobilization and the toxicity of three cytokine regimens administered after high-dose non-myeloablative chemotherapy with cyclophosphamide 5 g/m(2), etoposide 1.5 g/m(2) and cisplatin 150 mg/m(2). Thirty-five consecutive patients were non-random sequentially allocated to one of three treatment groups: (1) granulocyte colony-stimulating factor alone (n = 15); (2) granulocyte-macrophage colony-stimulating factor alone (n = 10), and (3) sequential interleukin-3 and granulocyte-macrophage colony-stimulating factor (n = 10). Neutrophil recovery in group 1 was significantly hastened as compared to the two other groups (median 2 days, p < 0.005), while no significant differences were observed between groups 2 and 3. CD34+ cells peaked about 2 days earlier in group 1 compared to the other groups (p = 0.0001), whereas the median peak value of CD34+ cells was similar in the three groups. In all patients, the toxicity related to cytokine administration was low and easily manageable with nonsteroidal anti-inflammatory drugs.

Autografting with Ph-negative progenitors in patients at diagnosis of chronic myeloid leukemia induces a prolonged prevalence of Ph-negative hemopoiesis

OBJECTIVE

In many patients with chronic myeloid leukemia (CML), a residual population of primitive normal (Ph-negative) progenitors persists despite the marked expansion of the leukemic (Ph-positive) clone. These cells may be found in the blood of patients studied soon after diagnosis or during the period of endogenous hematopoietic recovery that follows myeloreductive therapy. Based on those observations, we have developed a clinical protocol that allows collection of Ph-negative peripheral blood progenitor cells (PBPC) with transplantable hematopoietic regenerative potential. The aim of this study is to examine changes that occur in the percentage of Ph-negative- and Ph-positive-committed progenitor cells and to determine the relationship between changes and clinical outcome.

MATERIALS AND METHODS

We followed 15 patients with CML, mobilized and autografted soon after diagnosis with 85%-100% Ph-negative PBPC for a median time of 28 months (range 18-50) after transplant. At 6 months, 1 year, 2 years, and last follow-up, cytogenetic analyses were performed on fresh bone marrow cells and on colony-forming cells (CFC).

RESULTS

Autologous transplantation induces a reduction in the proportion of Ph-positive CFC, from 70%-100% to 0%-25% in the majority of patients (78%). After autografting, 8 of 15 patients achieved a long-lasting cytogenetic remission (median, 24 months; range, 21-43) with a Ph-positivity ranging between 0% and 20% at the level of mature mononuclear cells and colony-forming cells (CFC). In some patients, the majority of CFC remained Ph-negative, whereas the majority of the mature cells were Ph-positive. Other patients (5/15) developed cytogenetic relapse (100% Ph-positive), although they were in hematological remission. We found that detection of Ph-positive long-term-culture initiating cells (LTC-IC) in the marrow at diagnosis was the only factor significantly associated with recurrence of the disease (p < 0.01); on the other hand, the number of Ph-negative LTC-IC infused showed a significant correlation with a better outcome (p < 0.03).

CONCLUSION

We have shown that a prolonged period of complete or almost complete Ph-negative hemopoiesis can be achieved in patients with CML who undergo autografting with Ph-negative progenitors. Longer follow-up study will be needed to assess whether these changes are associated with improved survival.

Complex chromosome rearrangements may locate the bcr/abl fusion gene sites other than 22q11

BACKGROUND AND OBJECTIVE

From 5-8% of Philadelphia (Ph) positive patients with chronic myeloid leukemia (CML) show variant translocations in which at least a third chromosome in addition to 9q34 and 22q11 is involved. The formation mechanisms and clinical significance of variant Ph translocations are still unclear. The BCR/ABL chimeric gene encoding for chimeric proteins is always present and maps on the 22q- regardless of the type of translocation. We studied two apparently Ph negative CML patients with unusual karyotypes both showing a typical b3a2 rearrangement.

DESIGN AND METHODS

Dual-color fluorescence in situ hybridization (FISH) can visualize BCR and ABL genes and localize the BCR/ABL fusion gene. We used FISH to study the formation mechanisms of variant Ph translocations in two patients.

RESULTS

The chimeric BCR/ABL gene was located on a locus other than the expected 22q11 in both patients. In the first case the fusion signal was present on the 9q34 band whereas in the second patient it was detected on chromosome 8, involved in masked Ph formation.

INTERPRETATION AND CONCLUSIONS

The location of the hybrid BCR/ABL gene on chromosomes other than 22q- is a rare event which can only be observed using the FISH technique. When these unusual translocations occur the hypothesis most often put forward is that several consecutive cytogenetic events have taken place. The factors which regulate the formation of these breakpoints have yet to be clarified. The FISH technique allows the identification of chromosome rearrangements that could not otherwise be detected by conventional banding procedures. The location of the hybrid BCR/ABL gene on sites other than 22q11 represents a rare type of variant Ph translocation. The real frequency and clinical significance of such rearrangements need to be investigated.

Coexistence of normal and clonal haemopoiesis in aplastic anaemia patients treated with immunosuppressive therapy

Cytogenetic abnormalities and paroxysmal nocturnal haemoglobinuria (PNH) phenotype are frequent findings in aplastic anaemia patients treated with immunosuppressive therapy (IST). In this study we investigated whether the appearance of clonal haemopoiesis influences patient outcome and survival. 97 patients entered this study and were followed from the onset of the disease for a median follow-up (FU) of 53 months. 93% are alive, 56% achieved complete remission, 30% partial remission, both transfusion independent, and 14% did not respond. Three groups were identified: (A) patients without evidence of emerging clones (71/97); (B) patients who acquired chromosomal abnormalities (13/97); (C) patients who showed low expression of glycosyl phosphatidylinositol anchored proteins (GPI-AP) (PNH phenotype) at presentation or later (16/97). Three patients showed both PIG-AP deficiency and chromosomal abnormalities. The actuarial survival of patients without clonal haemopoiesis (n = 71) at 6 years was 95%, for patients with chromosomal abnormalities (n = 13), 88%, and for patients with PIG-AP deficiency (n = 16), 89%. There was no difference in the probability of becoming transfusion independent in the three groups (93%, 92% and 88% respectively). This study confirmed that a proportion of severe aplastic anaemia (SAA) patients exhibit clonal markers during the time after IST, often coexisting with cytogenetically or phenotypically normal haemopoiesis. There was no significant clinical impact of these abnormalities on transfusion independence and survival at the median follow-up of 4 years.

Relapse after allogeneic BMT for chronic myeloid leukemia (CML) may be sustained by a small number of leukemic 'stem cells': a hypothesis

'.the leukemic stem line is a small minority within the total cell mass;. when the leukemic stem line is not exceeding the normal stem cell numbers, its proliferation may still be under partial control.' LG Lajtha, Blood Cells 1981; 7: 45-62 We performed cytogenetic analysis on fresh bone marrow cells and on progenitor cell colonies in a patient who relapsed after allogeneic BMT for CML and was subsequently treated with donor lymphocyte infusions (DLI). Two Philadelphia-positive clones were identified at relapse. One clone displayed an additional chromosomal abnormality most likely induced by radio-chemotherapy and therefore arising in a single cell. This cell displays the characteristics of a stem cell, since it was able to support 20% of Ph-positive hemopoiesis for 5 months. If the progeny of a single Ph-positive stem cell account for 20% of hemopoiesis, a very low number of leukemic stem cells may sustain relapse after allogeneic BMT. This is in keeping with two observations: (1) at relapse, long-term culture initiating cells (LTC-IC) were all donor-derived and Ph-negative; (2) on average, the pace of the disease is very slow after relapse following allogeneic-BMT. Therefore, we hypothesize that a small number of leukemic stem cells may be involved in the initial events of relapse following BMT for CML.

Quantitative competitive reverse transcriptase-polymerase chain reaction for BCR-ABL on Philadelphia-negative leukaphereses allows the selection of low-contaminated peripheral blood progenitor cells for autografting in chronic myelogenous leukemia

The Philadelphia (Ph) translocation t(9;22) results in the creation of the BCR-ABL gene, which is now regarded as central to the mechanism that underlies the chronic phase of chronic myelogenous leukemia (CML). From a clinical point of view, BCR-ABL mRNA detection has become the basis for the study of minimal residual disease in CML, particularly when a complete cytogenetic remission is achieved after interferon-alpha (IFN-alpha) therapy or allogeneic stem cell transplantation. We have recently demonstrated that it is possible to mobilize normal peripheral blood progenitor cells (PBPC) in higher rates if this procedure is performed during the early chronic phase. In an attempt to monitor the leukemic cell content of PBPC collections, we used quantitative-competitive RT-PCR (QC-RT-PCR). Thirty consecutive Philadelphia (Ph) chromosome positive patients were enrolled in this study. After chemotherapy and G-CSF, 14 patients achieved 100% Ph-negative metaphases, nine patients had < or =34% and seven patients >34% leukemic metaphases. A total of 116 collection samples were studied. For each sample, BCR-ABL transcript numbers and BCR-ABL/ABL ratio were evaluated. A highly significant correlation between Ph-positive metaphases and BCR-ABL transcript numbers (r = 0.84, P < 0.0001) or BCR-ABL/ABL ratio (r = 0.86, P < 0.0001) was found. For patients that underwent the procedure in early chronic phase, Ph-negative collections showed different levels of BCR-ABL expression. BCR-ABL transcript numbers varied from a median of 100/microg RNA in the first and second leukaphereses, to 500/microg RNA in the third and fourth leukaphereses, and 1500/microg RNA in the fifth leukapheresis (P = 0.002). BCR-ABL/ABL ratio values showed similar kinetics. We have also demonstrated that there is a correlation between low values in BCR-ABL/ABL ratio (< or =0.01) in the reinfused PBPC and the achievement of cytogenetic remission after autografting (chi2 test, P = 0.01). In conclusion, this study demonstrates that QC-RT-PCR for BCR-ABL is a reliable and helpful method for monitoring residual leukemic load in mobilized PBPC, particularly in Ph-negative collections. Moreover, QC-RT-PCR allows selection of the best available collections for reinfusion into patients after myeloablative therapy.

Comparative effects of three cytokine regimens after high-dose cyclophosphamide: granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor (GM-CSF), and sequential interleukin-3 and GM-CSF

PURPOSE

To compare the toxicity and effects on hematologic recovery and circulating progenitor cell mobilization of three cytokine regimens administered after high-dose cyclophosphamide (HD-CTX; 6 g/m(2)), given as the first step of a high-dose sequential chemotherapy.

PATIENTS AND METHODS

Forty-eight patients with breast cancer or non-Hodgkin's lymphoma were randomized to receive granulocyte colony-stimulating factor (G-CSF) alone (arm 1), granulocyte-macrophage colony-stimulating factor (GM-CSF) alone (arm 2), or sequential interleukin-3 (IL-3) and GM-CSF (arm 3). Cytokines were administered as a single daily subcutaneous injection at a dose of 5 to 6 microg/kg/d. Progenitor cells were evaluated in peripheral blood as well as in apheretic product as both CD34(+) cells and granulocyte-macrophage colony-forming units (CFU-GM).

RESULTS

Neutrophil recovery was faster in arm 1 as compared with arms 2 and 3 (P <.0001); no significant differences were observed between arms 2 and 3. In arm 3, a moderate acceleration of platelet recovery was observed, but it was statistically significant only as compared with arm 1 (P =.028). The peak of CD34(+) cells was hastened in a median of 2 days in arm 1 compared with arms 2 and 3 (P =.0002), whereas the median peak value of CD34(+) cells and CFU-GM was similar in the three patient groups. Administration of IL-3 and GM-CSF resulted in more significant toxicity requiring pharmacologic treatment in 90% of patients.

CONCLUSION

The three cytokine regimens administered after HD-CTX are comparably effective in reducing hematologic toxicity and mobilizing the hematopoietic progenitor cells. G-CSF accelerates leukocyte recovery and progenitor mobilization. Although G-CSF-treated patients have somewhat slower platelet recovery, they definitely have fewer side effects.

Autografting with philadelphia chromosome-negative mobilized hematopoietic progenitor cells in chronic myelogenous leukemia

Intensive chemotherapy given in early chronic phase of chronic myelogenous leukemia (CML) has resulted in high numbers of circulating Philadelphia (Ph) chromosome-negative hematopoietic progenitor cells (HPC). We have autografted 30 consecutive patients with CML in chronic phase with HPC collected in this way to facilitate restoration of Ph-negative hematopoiesis in bone marrow after high-dose therapy. Hematopoietic recovery to greater than 0.5 x10(9)/L neutrophils and to greater than 25 x 10(9)/L platelets occurred in all patients, a median of 13 (range, 9 to 32) days and 16 (range, 6 to 106) days postautograft, respectively. Regenerating marrow cells were Ph-negative in 16 (53%) patients and greater than 66% Ph-negative in 10 (33%) patients. Twenty-eight patients are alive 6 to 76 months (median, 24 months) after autografting. Three patients have developed blast crisis from which 2 have died. Eight patients are in complete cytogenetic remission at a median of 20 (range, 6 to 44) months with a median ratio BCR-ABL/ABL of 0.002 (range, <0.001 to 0.01). Eight patients are in major cytogenetic remission at a median of 22 (range, 6 to 48) months. No patient died as a consequence of the treatment. All patients had some degree of stomatitis that was severe in 15 (50%) patients. Gastrointestinal and hepatic toxicities were observed in about one fourth of patients. Thus, autografting with Ph-negative mobilized HPC can result in prolonged restoration of Ph-negative hematopoiesis for some patients with CML; moreover, most autograft recipients report normal or near normal activity levels, suggesting that this procedure need not to be associated either with prolonged convalescence or with chronic debility.

Normal primitive haemopoietic progenitors are more frequent than their leukaemic counterpart in newly diagnosed patients with chronic myeloid leukaemia but rapidly decline with time

We carried out studies to quantify Ph-negative progenitors both in steady state and during regeneration after chemotherapy and G-CSF in 23 newly diagnosed chronic myeloid leukaemia (CML) patients (group A) and in 14 individuals more than a year from diagnosis (nine in chronic and five in accelerated phase, group B). In steady-state bone marrow, Ph-negative long-term culture initiating cells (LTC-IC) and Ph-negative colony-forming-cells (CFC) were detected in 18/23 and 14/23 patients of group A versus 3/14 and 3/14 patients of group B (P<0.001 and P<0.02, respectively). The absolute number of mobilized Ph-negative progenitors was markedly higher in group A versus group B (P<0.02 for LTC-IC, P<0.003 for CFC). 12/16 newly diagnosed patients mobilized Ph-negative LTC-IC only and the yield was in the range of normal allogeneic donors. Overall the frequency of Ph-negative LTC-IC in the bone marrow predicted the yield of Ph-negative LTC-IC mobilized into peripheral blood (P<0.001). The bone marrow frequency of Ph-positive LTC-IC was considerably lower than the normal counterpart. Taken together, these findings suggest that normal progenitors are relatively well preserved in newly diagnosed CML patients, but tend to rapidly decline with time. This observation helps in the understanding of the pathogenesis of CML and has potential implications for autografting. The optimal time for a successful collection of Ph-negative circulating progenitors would appear to be soon after diagnosis.

Complex structural involvement of chromosome 7 in primary myelodysplastic syndromes determined by fluorescence in situ hybridization

Cytogenetic analysis of 72 consecutive de novo myelodysplastic syndrome patients revealed monosomy 7 in 12 cases. In 4 of these cases, the -7 was the only abnormality, whereas the remaining 8 cases showed additional chromosomal aberrations. Fluorescence in situ hybridization (FISH) utilizing chromosome 7 alpha-satellite and painting probes and other specific probes, when necessary, provided evidence of unusual and unsuspected structural rearrangements involving chromosome 7. FISH analysis showed that the small fragment found in one patient and the ring found in each of two other patients were chromosome 7-derived rings. FISH also revealed the insertion of chromosome 7 sequences into autosomes in three other patients and unusual translocations in the remaining two patients. By comparing the results obtained by using banding techniques to those obtained by using the FISH technique, we deduced the involvement of chromosome 7 with partial deletion of the short arm in all eight examined patients. Our study confirms the ability of FISH to detect chromosomal aberrations that would otherwise not be identified and the tendency of chromosome 7 to be involved in many different rearrangements. From a clinical point of view, we confirm that patients affected by myelodysplastic syndromes with complex karyotypes involving chromosome 7 do not respond to treatment and have a poor prognosis.

Allogeneic hemopoietic stem cell transplantation for patients with high risk acute lymphoblastic leukemia: favorable impact of chronic graft-versus-host disease on survival and relapse

BACKGROUND AND OBJECTIVE

The best post-remission therapy for patients with acute lymphoblastic leukemia (ALL) is controversial, and hemopoietic stem cell transplantation (HSCT) is one therapeutic option. The goal of this study is to describe long term results of HSCT in high risk ALL patients.

DESIGN AND METHODS

Between 1978 and 1996, 170 patient with ALL and a median age of 22 years (1-49), underwent an allogeneic HSCT from HLA-identical siblings (n = 149), family mismatched donors (n = 18) or unrelated HLA matched donors (n = 3); 92% of patients had at least one adverse prognostic factor for high risk ALL at diagnosis; one third (33%) were in first remission (CR1) and the majority (85%) received an unmanipulated HSCT with cyclosporin-methotrexate prophylaxis of graft-versus-host disease (GvHD).

RESULTS

After a median follow-up of over 6 years, 59 patients are alive and 111 patients have died of leukemia (46%) or transplant related complications (54%). The actuarial 10 year survival is 53%, 38% and 20%, for patients in CR1, CR2 or advanced phase, respectively. The actuarial survival of patients with (n = 24) of without (n = 46) cytogenetic abnormalities, grafted in CR1/CR2 was respectively 45% and 48% (p = 0.5). The year of transplant had a significant impact in multivariate analysis on transplant related mortality (TRM) (p = 0.0009) but not on relapse (p = 0.3). Chronic GvHD was the most important favorable prognostic factor for survival (p = 0.0014) and relapse (p = 0.0019).

INTERPRETATION AND CONCLUSIONS

This study confirms that long term survival can be achieved with HSCT in ALL patients, even those with cytogenetic abnormalities. Transplant mortality has been significantly reduced in recent years, whereas leukemia rate relapse has remained unchanged: the latter is influenced by the occurrence of chronic GvHD. Immune intervention post-HSCT may be considered to address this problem.

Allogeneic bone marrow or peripheral blood cell transplants in adults with hematologic malignancies: a single-center experience

This is a retrospective study of 97 patients who received either allogeneic bone marrow transplant (BMT) (n=52) or peripheral blood cell transplant (PBCT) (n=45) at our institution from human leukocyte antigen (HLA)-identical sibling donors between January 1994 and January 1997. The two groups were comparable with respect to diagnosis, age, sex, interval from diagnosis, and disease phase. They were prepared with cyclophosphamide (CY) and fractionated total-body irradiation (TBI) (n=51) or CY and thiotepa (n=46). Graft-vs.-host disease (GVHD) prophylaxis consisted of cyclosporin A and methotrexate. Patients who received PBCT exhibited faster neutrophil engraftment (day 14 vs. day 16, p = 0.002) than those in the BMT group, as well as higher platelet counts on day 20 (32x10(9)/kg vs. 21x10(9)/kg, p = 0.001), but graft function as assessed by platelet counts on days 50, 100, and thereafter was comparable. The number of days spent in the hospital, days on intravenous antibiotics, and days of fever were lower in the PBCT group, but not significantly. Acute GVHD, chronic GVHD, and cytomegalovirus infections were comparable between the two groups. The overall actuarial 3-year transplant-related mortality (TRM) rate for BMT vs. PBCT patients was 20 vs. 33% (p = 0.1), the survival rate was 53 vs. 48% (p = 0.3), and the relapse rate was 42 vs. 43% (p = 0.8). For patients in first complete remission, these figures were TRM 12 vs. 22% (p = 0.2), survival rate 75 vs. 70% (p = 0.4) and relapse rate 31 vs. 9% (p = 0.4), respectively, for the BMT and PBCT groups. These data suggest that the short-term outcome of allogeneic PBCT is not significantly different from that of allogeneic BMT in patients with hematologic malignancies. Long-term results are not available at present.

The assessment of the hematopoietic reservoir after immunosuppressive therapy or bone marrow transplantation in severe aplastic anemia

We investigated the hematopoietic reservoir in 43 severe aplastic anemia (SAA) patients following immunosuppression (IS) (n = 15) or bone marrow transplantation (BMT) (n = 28), at a median interval of 5 years (range, 2-20) from treatment. All patients had normal blood counts, good marrow cellularity, and normal numbers of colony forming unit-granulocyte macrophages (CFU-GM). Burst forming unit-erythroid (BFU-E) and colony forming unit-granulocyte erythroid megakaryocyte macrophages (CFU-GEMM) numbers were reduced when compared with normal controls. However, the most pronounced defect was observed at the level of long-term culture-initiating cells (LTC-IC), which significantly differed from controls (P < .00001) both for IS and BMT patients. Their number did not improve with time and was not affected by transplant or treatment-related variables. When IS patients were compared with BMT we found comparable numbers of CFU-GEMM (P = .8) and LTC-IC (P = .9), but lower numbers of BFU-E and CFU-GM (P = .05 and P = .004, respectively), suggestive of a persistent suppressive mechanism. These data indicate that LTC-IC numbers are severely reduced in BMT and IS patients, contradicting the common belief that the former are fully reconstituted as compared with the latter. In addition, the number of mature cells and committed progenitors does not seem to reflect the real size of the hematopoietic reservoir and few stem cells may be sufficient to guarantee normal hematopoiesis long term.

Centralized cytogenetic analysis of pediatric acute leukemia: results of an Italian collaborative experience

BACKGROUND AND OBJECTIVE

Cytogenetic analysis of acute leukemia yields important information which has been demonstrated to be correlated to patient survival. A reference laboratory was created in order to perform karyotype analysis on all cases of acute leukemia enrolled in the AIEOP (Associazione Italiana Emato-Oncologia Pediatrica) protocols.

METHODS

From January 1990 to December 1995, 1115 samples of children with ALL or AML were sent in for cytogenetic analysis. The results of cell cultures were screened in the Reference Laboratory and then the fixed metaphases were sent to one of the six cytogenetic laboratories for analysis.

RESULTS

The leukemic karyotypes of 556 patients were successfully analyzed. An abnormal clone was detected in 49% of cases of ALL and in 66% of AML. In ALL the most frequent abnormality was 9p rearrangement. Other recurrent abnormalities were t(9;22), t(4;11) and t(1;19). In AML t(8;21), t(15;17) and 11q23 rearrangement were the most frequent structural abnormalities. These findings are similar to the results obtained in other multicenter studies using a similar approach.

INTERPRETATION AND CONCLUSIONS

Our data confirm the feasibility of performing cytogenetic analysis in a centralized laboratory on mailed samples of bone marrow and/or peripheral blood; this is very important considering that cytogenetic analysis of neoplastic tissue requires a special laboratory and expert staff.

High frequency of trisomy 8 in acute promyelocytic leukemia: a fluorescence in situ hybridization study

Correct diagnosis of acute promyelocytic leukemia (APL) requires proof of the translocation (15;17)(q24;q11), which appears to be absolutely specific for this particular type of myeloid disorder. We studied the karyotypes of 29 consecutive APL patients at diagnosis: in 5 of them banding techniques failed to detect the t(15;17). In these seemingly cytogenetically negative cases, fluorescence in situ hybridization (FISH) with a chromosome 17 painting probe detected a high percentage of mitoses with 3 hybridization signals: one derived from the intact chromosome 17, and 2 from the rearranged chromosomes 15 and 17. Trisomy 8 (+8) as a secondary chromosomal abnormality was observed in 8 cases (27.5%), confirming that the t(15;17) favors the acquisition of an extra chromosome 8. One of these 8 cases showed a marker that was interpreted by FISH analysis as der(8) with duplication of a segment of the long arm carrying the c-MYC allele. Clinical features of patients with t(15;17) and +8 were no different from patients with t(15;17) alone. The usefulness of FISH to standard banding techniques in the detection of specific structural and/or numerical chromosomal abnormalities is confirmed in this report.

Amplified c-MYC sequences localized by fluorescence in-situ hybridization on double minute chromosomes in acute myeloid leukemias

Double minute chromosomes (dmin) are small acentric fragments frequently observed when karyotyping human tumor cells. They are considered the cytogenetic manifestation of gene amplification. The finding of dmin in leukemia is a rare event usually associated with progression of the disease and unfavorable prognosis. We present four patients affected by myeloid disorders with an abnormal karyotype and a variable number of dmin. In an attempt to clarify the origin of the dmin and the amplified gene, we utilized a fluorescent in-situ hybridization (FISH) technique and a panel of specific probes. The results of the analysis indicate that, although chromosomes 8 are apparently uninvolved, dmin retained c-MYC sequencs in three cases. By observing previously reported cases, we found that the majority of patients with myeloid disorders and dmin showed an amplified c-MYC gene, regardless of the chromosomal abnormalities. The FISH technique proved to be informative in demonstrating gene amplification in both metaphase and interphase cells. Finally, in the one patient carrying a 20q deletion, FISH allowed the detection of a previously unreported translocation between a 16p and the 20q-, confirming the ability of the technique to understand complex karyotypes.

Donor lymphocyte infusions (DLI) in patients with chronic myeloid leukemia following allogeneic bone marrow transplantation

Donor lymphocyte infusions (DLI) were given between June 1990 and March 1996 to 18 patients with chronic myeloid leukemia (CML) for the treatment of cytogenetic (n = 6) or hematologic relapse (n = 12) following an allogeneic bone marrow transplant (BMT). Patients were divided in two groups: patients in group A (n = 8) received a large dose of donor lymphocytes (> or = 1 x 10(8)/kg), whereas patients in group B (n = 10) received escalating numbers of cells (2 x 10(5) up to 2 x 10(8)/kg). The median number of DLI in group A was 2 (range 1-3); the median number of infusions in group B was 7 (range 3-9). Acute GVHD occurred in 12 patients (grades I-III) and was a major cause of death in two. The risk of developing GVHD correlated with the number of cells infused: 37%, 14%, 5% and 0% for DLI with cells > or = 1 x 10(8), 2 x 10(7)/kg, 2 x 10(6)/kg, and 2 x 10(5)/kg, respectively (P = 0.01). Median transaminase levels were found to be significantly increased in patients with, as compared to patients without, acute GVHD (GPT 412 vs 28 IU/l; P = 0.03). Severe aplasia occurred in four and was a contributing cause of death in two patients. Overall, four patients died as a consequence of DLI and all received > 1 x 10(8)/kg cells: the actuarial risk was 38% in group A and 14% in group B (P = 0.1). There were 10 complete and three partial cytogenetic responses: the actuarial probability at 5 years of being Ph negative was 69%: it was 46% for group A and 85% for group B (P = 0.1). The longest patient is now 6 years post-DLI, Ph negative, BCR-ABL negative. The actuarial 3 year survival is 38% in group A and 86% in group B (P = 0.06). The study confirms that DLI post-BMT is not innocuous and that there is a definite long-lasting antileukemic effect in patients with CML. It also suggests that: (1) the risk of developing GVHD correlates with the number of infused cells; (2) that significant elevations of serum GPT levels are associated with GVHD; and (3) that the use of escalating doses of cells may allow the identification of side-effects and discontinuation of infusions before life-threatening GVHD has developed.

Duplication of the der(13)t(12;13)(p13;q14) in chronic myelomonocytic leukemia

A case of chronic myelomonocytic leukemia with a reciprocal translocation (12;13)(p13;q14) and other numerical and structural abnormalities is described. Most of the metaphases examined showed duplication of the der(13)t(12;13), leading to trisomy of the translocated segment of chromosome 12. Using fluorescence in situ hybridization we observed that the breakpoint on chromosome 13 is centromeric to the retinoblastoma gene. Since other cases with apparently similar t(12;13) have recently been reported, we conclude that this structural rearrangement may be a rare but non random event in hematologic disorders.

Mobilization and transplantation of Philadelphia-negative peripheral-blood progenitor cells early in chronic myelogenous leukemia

PURPOSE

Mobilization of Philadelphia (Ph) chromosome-negative progenitors is now possible in many Ph1-positive chronic myelogenous leukemia (CML) patients who had received interferon alfa (IFN-alpha) with no cytogenetic response. In this pilot study, we used this approach in patients without prior IFN-alpha therapy to determine if the number and quality of mobilized progenitors would be increased and to evaluate the potential effect of these cells as autografts.

PATIENTS AND METHODS

Twenty-two untreated patients were mobilized within 12 months of diagnosis. The treatment regimen consisted of the mini-ICE protocol. Beginning on day +8, granulocyte colony-stimulating factor (G-CSF) was used in all patients. Leukophoresis was performed as the patients were recovering from aplasia, when WBC count exceeded 0.8 x 10(9)/L.

RESULTS

In 14 patients, (63%) the leukophoresis product was entirely Ph1-negative and in four patients the Ph1-positive cell rate was < or = 7%. Significant numbers of long-term culture-initiating cells (LTC-IC) and CD34+ Thy1+Lin- cells were found in most of the Ph1-negative collections that were tested. Twelve patients underwent autografting with their mobilized peripheral-blood progenitor cells (PBPC) (Ph1-negative collections, 10 patients; major cytogenetic response, two patients). All patients engrafted and are alive; six have Ph1-negative marrow 7 to 15 months after autografting. Posttransplant treatment was IFN-alpha combined with interleukin (IL)-2 because of the recent demonstration of synergistic activity in augmenting cytolytic activity.

CONCLUSION

Intensive chemotherapy given in early chronic phase of CML is well tolerated and results in high numbers of circulating Ph1-negative precursor cells.

Spontaneous exodus of high numbers of normal early progenitor cells (Ph-negative LTC-IC) in the peripheral blood of patients with chronic myeloid leukaemia at the beginning of the disease

Elevated white blood cell counts are frequently found in patients with chronic myeloid leukaemia (CML). Although some studies have disclosed that bone marrow of CML patients may contain some normal Philadelphia-negative early progenitor cells, it has been assumed that the dramatic increase of white blood cells was entirely related to the leukaemic cell expansion. In this study we attempted to quantify the number of normal and leukaemic progenitor cells in the bone marrow and peripheral blood of newly diagnosed CML patients. Bone marrow and peripheral blood cells of eight newly diagnosed CML patients were analysed for clonogenic colony-forming cells (CFC) and very early progenitor cells, i.e. long-term culture initiating cells (LTC-IC). The leukaemic (Ph-positive) or normal (Ph-negative) origin of progenitor cells was revealed by cytogenetic analysis performed on single colonies arising from in-vitro assays. In 6/8 patients the marrow CFC frequency ranged from 400 to 9300/10(6) mononuclear cells (MNC), 0-50% being Philadelphia chromosome negative; the LTC-IC frequency ranged from 0 to 11/10(6) MNC, and were 80-100% Ph-negative. The corresponding absolute values into peripheral blood were: CFC = 1-35.5 x 10(3)/ml, 0-50% Ph-negative, and LTC-IC = 0-2.5 x 10(3)/ml, 0-100% Ph-negative. In one patient, no LTC-IC were detected in either the marrow or the peripheral blood. In conclusion, in the peripheral blood of some CML patients, the number of normal LTC-IC is more than 3 times the number of leukaemic progenitor cells, and is much higher (50 times) than the corresponding value found in normal subjects in steady state (2.5/ml v 124/ml). These data support the concept that leukaemic 'stem cells', with respect to normal ones, may be considerably fewer than previously thought. In addition it is shown that at the beginning of CML high numbers of normal LTC-IC are spontaneously mobilized into the blood. Finally, the presence of Ph-negative early progenitors into the blood may represent a potential source of normal stem cells available for autografting providing they can be separated from leukaemic cells.

High-dose mitoxantrone with peripheral blood progenitor cell rescue: toxicity, pharmacokinetics and implications for dosage and schedule

The optimal use of mitoxantrone (NOV) in the high-dose range requires elucidation of its maximum tolerated dose with peripheral blood progenitor cell (PBPC) support and the time interval needed between drug administration and PBPC reinfusion in order to avoid graft toxicity. The aims of this study were: (1) to verify the feasibility and haematological toxicity of escalating NOV up to 90 mg m(-2) with PBPC support; and (2) to verify the safeness of a short (96 h) interval between NOV administration and PBPC reinfusion. Three cohorts of ten patients with breast cancer (BC) or non-Hodgkin's lymphoma (NHL) received escalating doses of NOV, 60, 75 and 90 mg m(-2) plus melphalan (L-PAM), 140-180 mg m(-2), with PBPC rescue 96 h after NOV. Haematological toxicity was evaluated daily (WHO criteria). NOV plasma pharmacokinetics was also evaluated, as well as NOV cytotoxicity against PBPCs. Haematological recovery was rapid and complete at each NOV dose level without statistically significant differences, and there were no major toxicities. NOV plasma concentrations at the time of PBPC reinfusion were below the toxicity threshold against haemopoietic progenitors. It is concluded that, when adequately supported with PBPCs, NOV can be escalated up to 90 mg m(-2) with acceptable haematological toxicity. PBPCs can be safely reinfused as early as 96 h after NOV administration.

High efficacy of fludarabine-containing therapy (FLAG-FLANG) in poor risk acute myeloid leukemia

BACKGROUND

Elderly patients with acute myeloid leukemia (AML) those refractory to induction chemotherapy and those with so-called secondary leukemia have unfavorable prognoses and require innovative therapeutic approaches. Fludarabine allows an increased accumulation of Ara-CTP in leukemic cells and inhibits DNA repair mechanisms; therefore its association with Ara-C and mitoxantrone results in a synergistic effect.

MATERIALS AND METHODS

From May 1993 to February 1996, fludarabine-containing regimens (FLAG and FLANG) were employed as induction therapy in 51 high-risk AML patients. Diagnosis of AML in 22 patients was preceded by a myelodysplastic syndrome lasting more than six months; 8 of the 29 de novo AML cases (28%) were refractory to previous chemotherapy, 9 (31%) were treated for early relapse, 12 (41%) presented poor prognostic factors at diagnosis. The median age was 64 (range 33-76) years and the FAB subtypes were the following: M0 3, M1 5, M2 28, M4 7, M5 8. Forty-eight per cent of patients showed poor prognosis chromosomal abnormalities. FLAG (24 patients) consisted of both fludarabine 30 mg/sqm over 30 minutes followed 4 hours later by Ara-C 2 g/sqm over 4 hours (for 5 days) and G-CSF 300 micrograms/day administered 12 hours before fludarabine, for a total of 5 doses. FLANG (27 patients) had a shorter duration (3 days), reduced Ara-C dosage (1 g/sqm) and administration of mitoxantrone (10 mg/sqm) at the end of Ara-C infusion.

RESULTS

Recovery of both neutrophils (PMN > 0.5 x 10(9)/L) and platelets (Plt > 20 x 10(9)/L) required a median of 16 days from the end of therapy. Overall, 30 patients (59%) achieved CR, 6 (11%) PR and 10 (20%) were refractory; 5 (10%) experienced early death (cerebral hemorrhage or infection). The length of complete response ranged from 2 to 26 months with a median follow-up of 8 months. De novo and secondary AML registered 62 and 54% CR rates, respectively. Eight out of 10 patients refractory to conventional schemes achieved CR (80%) but only 3 out of 10 treated for relapse obtained CR (30%).

CONCLUSIONS

FLAG and FLANG showed similar activity and toxicity while proving to be highly effective and relatively well-tolerated treatments for high-risk de novo AML. Secondary leukemias seemed to be responsive as well, but the presence of an unfavorable karyotype alteration lowered the response rate.

In vivo mobilization of karyotypically normal peripheral blood progenitor cells in high-risk MDS, secondary or therapy-related acute myelogenous leukaemia

We have previously reported that mobilization of Philadelphia (Ph) chromosome-negative progenitors is possible in a significant number of Ph1-positive acute lymphoblastic leukaemia (ALL) and chronic myelogenous leukaemia (CML) patients. In this pilot study we employed the same approach for patients with RAEB-t, secondary AML (sAML) and therapy-related AML (t-AML). All patients except one had double or complex cytogenetic abnormalities in marrow cells before mobilization therapy. All patients received an idarubicin-containing regimen (mini-ICE protocol) followed by rh-G-CSF and the first leukapheresis was performed as they were recovering from aplasia. In six out of nine patients the leukapheresis product was entirely karyotypically normal, combined with a significant number of CFU-GM. CD34+ cells and LTC-IC. Recovery time from mobilization therapy was short and no patient died as a result of the procedure. To date, three patients have undergone autografting using their karyotypically normal collections, of which two (sAML) are alive with karyotypically normal marrow a few months after autografting.

Granulocytes with segmented nucleus retain normal chromosomes 17 in Philadelphia chromosome-positive chronic myeloid leukemia with i(17q) and pseudo-Pelger anomaly. A case report studied with fluorescence in situ hybridization

Previous reports suggested a correlation between the deletion of the terminal region of the short arm of a chromosome 17 and the appearance of dysgranulopoiesis in myeloproliferative disorders. Using the dual-color fluorescence in situ hybridization technique we analyzed the bone marrow and peripheral blood cells of a Philadelphia chromosome-positive chronic myeloid leukemia (CML) patient showing at the onset of transformation into blastic crisis both metaphases with the i(17q) as well as granulocytes without nuclear segmentation. This phenomenon is defined as pseudo-Pelger-Huët anomaly. Using two probes, one specific for 17p and one for 17q, we determined the presence or absence of the i(17q) in both metaphase and interphase cells. Moreover, we observed that all cells with a polysegmented nucleus typical of mature granulocytes did not have i(17q) but had two normal chromosomes 17. This observation confirmed the correlation between 17p deletion and the appearance of pseudo-Pelger anomaly. This finding may also be useful from a clinical point of view: the appearance of pseudo-Pelger cells in CML indicates that 17p deletion actually occurred. This event implies a negative prognosis.

Cytogenetic abnormalities in patients with severe aplastic anemia

BACKGROUND

Cytogenetic abnormalities have been described in a few patients with otherwise typical severe aplastic anemia (SAA), and the possible clonal nature of this disease is a controversial issue.

MATERIALS AND METHODS

Sixty-nine patients with acquired severe aplastic anemia underwent cytogenetic examination on bone marrow cells at the time of diagnosis (n = 34) and/or at least twice after immunosuppressive therapy (IS) (n = 35).

RESULTS

We identified 2 major groups. Group A: 51 patients (74%) were normal and remained normal. Group B: 18 patients (26%) had at least one abnormal cytogenetic analysis. This second group could be further subdivided as follows: (B1) chromosomal abnormalities not present at first examination and acquired in the course of the disease (n = 7); (B2) clonal cytogenetic abnormalities present at first examination and persisting (n = 3); (B3) reversible cytogenetic abnormalities (n = 8). The most frequent abnormality was trisomy 8 (n = 8) followed by monosomy 7 (n = 2); 82% of patients are alive in group A and 61% in group B. Three patients developed acute leukemia, all from group B. This represents 4% of all patients or 17% of those with at least one abnormal cytogenetic test.

CONCLUSIONS

Thus the majority of SAA patients have normal karyotypes in marrow cells at presentation and at follow-up. Patients with abnormal karyotypes exist and can be further subdivided into those with reversible and those with persistent abnormalities. The latter are at risk of developing myelodysplasia or acute leukemia.

Thiotepa cyclophosphamide followed by granulocyte colony-stimulating factor mobilized allogeneic peripheral blood cells in adults with advanced leukemia

Thirty-one patients (median age, 44 years) with advanced hematologic malignancies were given thiotepa 15 mg/kg, and cyclophosphamide 120 (n = 14) or 150 (n = 17) mg/kg followed by unfractionated peripheral blood stem cell transplants (PBSCT) from genotypically identical siblings (n = 28) or one antigen mismatched family donor (n = 3). Donors were mobilized with granulocyte colony-stimulating factor 5 to 10 microgram/kg/d for 6 days and underwent two to three leukapheresis on days +5, +6, +7. The median cell yield per donor expressed/kg of recipients body weight was as follows: nucleated cells 13 x 10(8)/kg; CD34+ cells 6 x 10(6)/kg; colony-forming unit-granulocyte macrophage 38 x 10(4)/kg, and CD3+ cells 449 x 10(6)/kg. The diagnoses were chronic myeloid leukemia (n = 4), acute myeloid (n = 9) or lymphoid leukemia (n = 2), acute myelofibrosis (n = 2), multiple myeloma (n = 1), lymphoma (n = 6), chronic lymphocytic leukemia (n = 1) myelodysplasia (n = 6). Twenty-eight patients had advanced disease, 29 patients were first grafts, and 2 were second transplants 3 and 9 years after the first. Neutrophil counts of 0.5 x 10(9)/L and platelet counts of 30 x 10(9)/L platelets were both achieved on day +14 (median). Engraftment could be proven by sex markers or DNA polymorphism in 29 of 31 patients: one had early leukemia relapse and one patient was unevaluable because of early death. Acute graft-versus-host disease (GVHD) was scored as minimal or absent (grade 0 to 1) in 14 patients, moderate (grade II) in 13, and severe (grade III to IV) in four. Causes of death were leukemia (n = 4), acute GVHD (n = 4, with associated cytomegalovirus infections in three), sepsis (n = 1), liver failure (n = 1), multiorgan failure (n = 1), and hemorrhage (n = 1). The actuarial transplant mortality is 29%, the actuarial relapse rate 22%. Nineteen patients survive with a median follow up of 288 days (100-690). The actuarial 2-year survival is 57%. Three patients received PBSCT from family donors mismatched for one class II antigen: all engrafted, one developed grade I aGVHD; one died of leukemia on day +155; two are alive disease free 267 to 290 days postgraft. This study suggests that thiotepa cyclophosphamide followed by unfractionated PBSC allograft may be an alternative form of transplant for adults with advanced leukemia, also in the setting of one antigen mismatched donor. The engraftment is rapid with acceptable GVHD and relatively low transplant-related mortality.

Loss of telomeric sequences in a ring derived from chromosome 8 in refractory anemia with excess of blasts in transformation

Using the fluorescence in situ hybridization technique, we analyzed a ring chromosome that appeared as a karyotype evolution in a patient affected by refractory anemia with excess of blasts in transformation. Metaphases hybridized with a chromosome-8-specific centromeric probe indicated that the ring retained the centromere of chromosome 8. Successively, utilizing a probe specific for all human telomeres, we observed that the ring lost telomeric sequences. This study demonstrated that the formation of a ring chromosome in hematologic disorders can cause loss of genetic material not revealed by banding techniques and therefore providing further proof of the advantages of molecular cytogenetic techniques.

Autografting Ph-negative blood precursor cells in chronic myeloid leukaemia

The study was devised to evaluate whether it was possible to collect Philadelphia-negative precursor cells in patients with chronic myeloid leukaemia. The approach was based on previous experience showing that complete remission (Ph-negative bone marrow cells) is rarely achieved after chemotherapy and is very short-lasting. We decided to explore whether it was possible to collect Ph-negative precursor cells in peripheral blood during the early phase of haemopoietic recovery. These data show that: the collection of Ph-negative precursor cells occurred in 12/16 (75%) patients mobilized within one year of diagnosis (group A) versus 12/33 (36%) in patients with a history of more than one year of disease (group B). Furthermore the numbers of Ph-negative precursor cells were significantly much higher at diagnosis. Ten patients mobilized at diagnosis were subsequently autografted with such Ph-negative precursor cells. Five of them remain Ph-negative from 4 to 12 months while the other five have percentages of Ph-positive cells in their marrow ranging from 20% to 70%. In this stage of the disease the procedure is safe and associated with a very good compliance. Occasional restoration of Ph-negative haemopoiesis could be observed up to 40 months after autograft, in patients of group B, but most of patients revert to Ph-positive haemopoiesis. in conclusion these data suggest that it is possible to restore Ph-negative haemopoiesis in 70% of patients mobilized at diagnosis. This percentage represent the highest one can obtain without allogeneic BMT, and this includes patients who never would have been cytogenetic responders to IFN-alpha. Whether and how long for Ph-negative status can be maintained is a matter for future observation and study.

Fluorescence in situ hybridization provides evidence for two-step rearrangement in a masked Ph chromosome formation

A chronic myelogenous leukemia (CML) patient with a masked Ph chromosome due to the translocation (9;10;22)(q34;q24;q11) is reported. Banding analysis showed a 9q+ chromosome typical of standard t(9;22)(q34;q11), and fluorescence in situ hybridization studies confirmed the involvement of a chromosome 10 in the masked Ph formation and also the presence of 3' ABL-DNA sequences in the der(22). This complex rearrangement could be explained by two consecutive translocations: the first, a standard t(9;22) (q34;q11), the second, a translocation between a chromosome 10 and the der(22) with a breakpoint in sequences derived from chromosome 9 telomeric to the ABL gene. By reverse transcription polymerase chain reaction (RT-PCR), we studied the BCR/ABL transcript junction: a chimeric m-RNA b3-a2, indicating a breakpoint within the major breakpoint cluster region, was found.

bcr/abl chimeric transcript in patients in remission after marrow transplantation for chronic myeloid leukemia: higher frequency of detection and slower clearance in patients grafted in advanced disease as compared to patients grafted in chronic phase

The polymerase chain reaction (PCR) was used to amplify the bcr/abl transcript as a marker of minimal residual disease (MRD) in 76 patients with chronic myeloid leukemia (CML) subjected to allogeneic BMT and in complete hematological remission. We examined 56 patients transplanted in chronic phase (CP) and 20 in advanced phase (AD), including 16 in accelerated phase and four in blastic transformation. A total of 135 samples collected between 4 and 105 months from BMT were analyzed and the PCR analysis was positive in 33 (24%) samples from 20 patients. The bcr/abl chimeric transcript was detected in 7/13 (54%) patients analyzed within 1 year and in 21/88 (23%) beyond 1 year from BMT. Fluctuation of the residual disease at the molecular level in individual patients was recorded. The results have been correlated with a number of clinical parameters obtained before and after BMT; among the tested variables only the phase of the disease at BMT was associated with higher frequency of PCR positivity after BMT. The probability of finding persisting disease 1 year beyond BMT was significantly higher (P = 0.00005) in patients allografted in AD (14/26, 54%) as compared to patients grafted in CP (7/62, 11%). At any interval from BMT the difference between the two groups remained statistically significant: the bcr/abl transcript was present in 5/31 patients transplanted in CP compared to 9/15 patients transplanted in AD (P = 0.003) between 12 and 36 months from BMT, and in 2/31 CP vs 5/11 AD patients (P = 0.008) beyond 36 months from BMT.(ABSTRACT TRUNCATED AT 250 WORDS)

Very primitive hemopoietic cells (LTC-IC) are present in Philadelphia negative cytaphereses collected during early recovery after chemotherapy for chronic myeloid leukemia (CML)

We have previously demonstrated that Philadelphia negative (Ph-ve) hemopoietic cells can be collected by leukaphereses after an acute leukemia-like chemotherapy during the early hemopoietic recovery in patients with chronic myeloid leukemia (CML). In this study we have evaluated whether these collections contain very primitive hemopoietic cells defined as 'long-term culture initiating cells' (LTC-IC) and whether these cells belong to the Ph-positive or Ph-negative population. Twenty-eight out of 76 cytaphereses collected in 15 patients with CML proved to contain Ph-ve cells only (six patients), 21 showed only Ph+ve cells (five patients), and 27 a mixture of Ph+ve and Ph-ve cells (four patients). In cytaphereses containing Ph-ve cells only, we found variable numbers of LTC-ICs, more consistently when we mobilized patients in the first 3 months from diagnosis. In three cases cytogenetic analysis on LTC-ICs and CFU-GM confirmed results obtained on fresh samples. Ph-positive collections were devoid of LTC-ICs except for 2/21 samples. However, their cytogenetic analysis revealed a small number of Ph-negative progenitors. LTC-ICs were randomly detected in mixed (Ph+ve and Ph-ve) collections. In conclusion these data indicate that, in a consistent proportion of chronic myeloid leukemia patients, intensive chemotherapy is able to recruit Ph-ve LTC-ICs in to the peripheral blood. Moreover these data provide the biological basis for developing autografting programs with Ph-negative cells.

Chronic clonal myeloproliferative disease associated with a t(5;21) translocation. Complete but transient hematologic and cytogenetic remission induced by interferon-alpha

A patient with a chronic myeloproliferative disease associated with a 100% t(5;12) translocation was treated with 3 million U per day of IFN-alpha 2a. Besides being consistently Ph-negative, the search for BCR/ABL hybrid transcripts by means of RT-PCR was also negative. Total cytogenetic conversion to diploid hematopoiesis was obtained, but after discontinuation of IFN a 50% relapse of t(5;21) mitoses was found, and treatment was resumed. There is some degree of consensus that the mechanism by which IFN-alpha suppresses the Ph+ clone in CML consists in the restoration of normal adhesion of CML progenitors to the marrow stroma, by preventing transcription of the BCR/ABL mRNA, and hence expression of the p210 tyrosine kinase. However, if the 'faulty adhesion' hypothesis, and its correction by IFN-alpha, is to be considered correct, this case proves that it must include also Ph-negative, not BCR-ABL rearranged clonal myeloid proliferations.

Four-step high-dose sequential chemotherapy with double hematopoietic progenitor-cell rescue for metastatic breast cancer

PURPOSE

High-dose chemotherapy produces high complete remission (CR) rates and some survival advantage in patients with metastatic breast cancer (BC). A current issue is the possibility that these patients may have an even better prognosis with multiple high-dose treatments. In this study, we evaluated the feasibility of a four-step, high-dose sequential chemotherapy (HDSC) with double autologous hematopoietic progenitor-cell rescue. We also tested the hypothesis that peripheral-blood progenitor cells (PBPCs) harvested following a single recruitment with cyclophosphamide (CY) and granulocyte-macrophage colony-stimulating factor (GM-CSF) allow the safe administration of the whole HDSC with closely timed repeated courses of several non-cross-resistant agents.

PATIENTS AND METHODS

The treatment plan included CY 7 g/m2, followed by GM-CSF 5 to 7 micrograms/kg/d administered by continuous intravenous (i.v.) infusion on days 2 to 14; PBPCs with or without bone marrow (BM) harvest; mitoxantrone (NOV) 60, 75, or 90 mg/m2 plus melphalan (L-PAM) 140 to 180 mg/m2 with hematopoietic rescue; methotrexate (MTX) 8 g/m2 plus vincristine (VCR) 1.4 mg/m2; and etoposide (VP-16) 1.5 g/m2 plus carboplatin (PP) 1.5 g/m2 with hematopoietic rescue.

RESULTS

All 15 patients enrolled completed the entire treatment and there were no toxic deaths. Hematologic reconstitution was good at each step. The median number of days with an absolute neutrophil count (ANC) less than 100/microL and platelet count less than 20,000/microL were 8 and 3, respectively, after NOV plus L-PAM, and 7 and 4, respectively, after VP-16 plus PP. The main non-hematologic toxicity was mucositis, while organ toxicity was mild and reversible.

CONCLUSION

This regimen is feasible, with acceptable toxicity. GM-CSF and PBPCs have a pivotal role, as they hasten hematologic reconstitution, abate toxicity, and allow rapid recycling.

Cytogenetic clonality in chronic myelomonocytic leukemia studied with fluorescence in situ hybridization

Chronic myelomonocytic leukemia (CMML) is a myelodysplastic syndrome (MDS) subtype, characterized by monocytosis, dysgranulocytosis and a low number of blast cells in the peripheral blood (PB). The clonal nature of MDS has been demonstrated by various techniques: the stem cell involved initially is capable of myeloid and lymphoid differentiation. Fluorescent in situ hybridization (FISH) is a technique which can be utilized without any pretreatment on whole interphase cells. In this study leukocytes of PB Wright-stained smears from four CMML patients with trisomy 8 (three cases) and 9 (one case) have been analyzed by FISH. Utilizing a probe for the centromere of chromosome 8 and for the heterochromatic region of chromosome 9, we observed the cells involved by trisomy. In each of the four cases neutrophils, eosinophils, basophils and monocytes may show trisomy 8 or 9, whereas lymphocytes resulted disomic. The comparison between leukocytes morphology and genotype suggests that the supernumerary chromosome does not influence cellular differentiation and maturation. We conclude that FISH analysis of PB leukocytes of patients with CMML is informative when studying the clonality of the disease. Chromosomal abnormalities seem to involve a hematopoietic cell committed to myeloid but not lymphoid differentiation. Trisomies 8 and 9 seem to confer some proliferative advantage without influencing the morphologic characteristics of leukocytes. Other causes will be investigated to explain dysmorphisms of neutrophils and monocytes typical of this disease.

Clonality study by fluorescence in situ hybridization of a patient with refractory anemia with ringed sideroblasts and monosomy 7

Myelodysplastic syndromes (MDS) are stem cell diseases but it is still controversial whether chromosomal abnormalities occurring in these disorders affect a multipotent stem cell or a committed progenitor. We studied a case of refractory anemia with ringed sideroblasts (RARS) and monosomy 7 in 100% of examined metaphases. Using the fluorescence in situ hybridization (FISH) technique with a probe specific for the centromeric region of chromosome 7, we demonstrated that 15% of BM cells fixed in acetic acid/methanol exhibited a normal diploid karyotype. Applying the FISH technique on PB cells smeared onto a slide, we observed that lymphocytes maintain two chromosomes 7, whereas other leukocytes exhibited monosomy 7. Our study confirms that chromosomal abnormalities found in MDS can occur in cells capable of differentiation along granulocytic and monocytic lineages, but not along the lymphocytic lineage.

Chromosome derived from translocation(1;17) retains alphoid sequences of both chromosomes involved

Examining a bone marrow (BM) karyotype of a patient with a refractory anemia with excess of blasts (RAEB), we detected a clone with an unbalanced translocation(1;17), resulting in monosomy of 17p and trisomy of 1q. Using fluorescence in situ hybridization (FISH) technique with alpha-satellite DNA probes specific for chromosomes 1 and 17, we observed that the chromosome derived from the translocation shows hybridization signals for both the centromeres of chromosomes 1 and 17. This finding suggests that the breakpoints of the two autosomes involved in the rearrangement occurred in the primary constriction. The case confirms the ability of ISH analysis to detect structural rearrangements in cancer cytogenetics.