Necrotising dermatitis in refractory acute myeloid leukaemia

Severe cutaneous infections in leukaemic patients are difficult to treat and can rapidly become fatal. We report on a case of essential thrombocythemia evolved to a myelodysplastic syndrome and finally, to an overt myeloid leukaemia, refractory to chemotherapy. In the presence of a marked neutropenia, the patients developed a wide Staphylococcus epidermidis necrotising dermatitis. The diagnosis was made possible only by a skin biopsy culture and the antibiotic treatment, based on antimicrobial susceptibility tests, rapidly resolved the infection. In neutropenic patients, appropriate laboratory tests and treatment, can lead to recovery of life-threatening infections.

Helicobacter pylori eradication can induce platelet recovery in idiopathic thrombocytopenic purpura

Recent reports have suggested an association between Helicobacter pylori infection and idiopathic thrombocytopenic purpura (ITP). The prevalence of H pylori infection and the effect of its eradication in a series of 30 ITP patients were investigated. H pylori infection has been documented in 13 patients (43.33%) by 13C urea breath test and confirmed by histologic examination. Bacterium eradication with antibiotics, obtained in 12 of 13 infected patients (92.3%), led to a complete response in 4 (33.33%) and to a partial response (platelets 90 x 10(9)/L-120 x 10(9)/L) in 2 (16.66%). The response was maintained for a median of 8.33 months, but 1 patient relapsed 7 months after eradication. Search for H pylori infection seems appropriate in ITP patients at diagnosis. Bacterium eradication provides a new good option for a nonimmunosuppressive treatment in some ITP patients.

Late-appearing PML/RARalpha fusion transcript with coincidental t(12;13)(p13.2;q14) in acute promyelocytic leukemia lacking the t(15;17) cytogenetic anomaly

The late appearance of a cytogenetic/molecular hallmark in human leukemias is a rare event. We report on a case of acute myeloid leukemia with morphology, immunophenotype and clinical features typical of promyelocytic subtype (APL), in which the specific PML/RARalpha gene rearrangement was molecularly detected only at second relapse of disease, without cytogenetic evidence of the t(15;17). The emergence of the PML/RARalpha gene may be therapy-related or may represent the exceptional result of a clonal evolution during progression of neoplasia. At second relapse, a novel cell clone bearing a t(12;13)(p13.2;q14) was also observed and a molecular deletion and rearrangement of a locus at 13q14, distinct from retinoblastoma (Rb1) locus, was found. In this unusual case, the PML/RARalpha product seems to be not essential for the expression of the promyelocytic phenotype at diagnosis and, when detectable, it is not the sole genetic defect.

Chronic myeloid leukemia with thrombocythemic onset may be associated with different BCR/ABL variant transcripts

Ph-positive chronic myeloid leukemia (CML) mimicking essential thrombocythemia (ET) at onset seems to be a distinct clinical entity. Whether this rare clinical form of CML is associated with single, specific variants of BCR/ABL transcripts is a matter of debate. Among 82 consecutive patients with Ph-positive CML, we identified 3 patients in which the disease mimicked ET at presentation, because of marked thrombocytosis and moderate leukocytosis, with few immature myeloid cells in peripheral blood and blood basophilia in 2 of them. Molecular analysis with the reverse transcriptase-polymerase chain reaction technique showed the presence of b2a2, b3a2, and b3a2-b2a2 transcript variants in the three patients, respectively. The results of our study together with a review of literature data suggest that different BCR/ABL transcript variants may occur in CML mimicking ET, without an apparently significant prevalence of one type.

Occurrence of a novel t(11;19)(q13;q13.3) in complete remission of acute promyelocytic leukemia

A woman with t(15;17) and PML/RAR alpha positive acute promyelocytic leukemia (APL-M3v) achieved a complete remission (CR) with cytogenetic and molecular conversion, after one-month ATRA plus idarubicin treatment. During CR, less than one-month after consolidation therapy with topoisomerase II inhibitors, a novel t(11;19) (q13;q13.3) was detected in peripheral blood stem cells and later in harvest bone marrow cells. Persisting CR and the negativity for BCL1 and PRAD1 genes rearrangement, the autotransplantation was performed, with good outcome. The patient is still in CR eighteen months post-transplant, in spite of the persistence of a small t(11;19) clone in BM cells. The emergence of a novel chromosomal change during CR of acute leukemia is a rare phenomenon. This is the first t(11;19)(q13;q13.3) described in APL. This finding raises the issue of whether the abnormal karyotypes at remission might represent a risk of tumor recurrence. The meaning of this genomic instability is yet unknown.

Hepatitis C virus-induced leuko-thrombocytopenia and haemolysis

Hepatitis C virus (HCV) has been recognized as the cause of thrombocytopenia occurring in patients with chronic hepatitis C, possibly through autoimmune mechanisms. A patient is described with B cell chronic lymphocytic leukaemia, presenting with a marked leuko-thrombocytopenia and an associated mild haemolysis secondary to HCV infection, in the absence of clinical and biochemical signs of hepatitis. Anti-HCV antibodies were detected in the serum both by ELISA and RIBA but not 2 months before the onset of cytopenia. The presence of HCV RNA was documented both in the peripheral blood mononuclear cells and in the bone marrow by reverse transcriptase polymerase chain reaction of the 5' untranslated region of the viral genome. Of interest, HCV RNA was also found in the serum, showing that viraemia was associated with the presence of circulating anti-HCV antibodies. HCV genotyping, performed by PCR amplification of the core region, revealed the presence of an unclassifiable genotype. The hypothetical mechanisms leading to HCV-induced cytopenia in this patient are briefly discussed. Treatment with corticosteroids was effective in controlling blood cell counts, without increasing viraemia and deterioration of liver disease. HCV infection should be considered in the differential diagnosis of possible causes of cytopenia, mainly in immunosuppressed patients, even in absence of clinical and biochemical signs of hepatitis.

Additional neoplasms and HCV infection in low-grade lymphoma of MALT type

Several chronic inflammatory conditions and genetic alterations are likely to be involved in the pathogenesis of low-grade lymphoma of MALT type. In a well-characterized series of 27 patients with low-grade lymphoma of MALT type, we studied: (1) the incidence of other neoplasms, which might be indicative of genetic instability, apparently a characteristic of this disease; (2) the prevalence of serologic and molecular markers of HCV infection, which has been found in association with other lymphoproliferative disorders. Three patients had one or more additional cancers; a total of eight tumours, five of which occurred in the same patient, suggests the presence of some genetic instability in at least some cases of the disease. Rather unexpectedly, anti-HCV antibodies and HCV RNA sequences were documented in 50% of the patients examined, without elevation of serum transaminases. Of interest, the two patients with parotid and conjunctival MALT lymphomas, respectively, with a previous history of Sjögren's syndrome, were HCV positive. We suggest, for the first time, that HCV may be considered, in addition to Helicobacter pylori, as another potential infectious co-factor in the multistep pathogenesis of low-grade lymphomas of MALT type.

Long-term salvage treatment by cyclosporin in refractory autoimmune haematological disorders

We report on long-term treatment (13-62 months) with cyclosporin A (CyA) in eight patients with autoimmune haematological disorders, resistant to all usual therapies. Three patients had an autoimmune haemolytic anaemia (AHA); four an idiopathic thrombocytopenic purpura (ITP), and one an Evans syndrome. All patients were responsive: six achieved complete remission and two partial remission. The side-effects were moderate and transient. The majority of surviving patients remain dependent on continued drug administration. The CyA appears to be recommendable as a salvage treatment in life-threatening, resistant autoimmune haematological diseases.

YAC clone H10 discriminates between 3q26.2 and 3q27 chromosome rearrangements in hematological disorders

To discriminate with molecular-cytogenetic resolution between 3q26.2 breakpoint, associated to various myeloproliferative disorders, and 3q27 breakpoint, recurrent in several types of non-Hodgkin lymphoma, we tested the feasibility of using a yeast artificial chromosome, YAC clone H10, mapped on 3q26.3. Fluorescent in situ hybridization of the biotinylated polymerase chain reaction product of the YAC H10 was performed in three myeloproliferative diseases and one follicular non-Hodgkin lymphoma carrying different rearrangements of chromosome 3 involving region q26-q27. Our study shows that YAC H10 signal was telomeric to all three myeloid breakpoints, while it was centromeric in the lymphoid one thus showing that this probe can discriminate between these two subsets of chromosome 3 rearrangements. These results point out the opportunity of using additional YACs in the characterization of polymorphic chromosome alterations acquired in neoplastic cells.

Chromosome rearrangements at telomeric level in hematologic disorders

Following retrospective screening of our karyotype data from 414 consecutive non-childhood, neoplastic, and preneoplastic hematologic diseases, we have isolated 11 cases with alterations involving one or two chromosome termini, including: a) nonclonal telomeric telomeric associations (tas), b) subclonal terminal rearrangements consisting of additional (add) material of unknown origin fused at the end of the chromosome, c) clonal telomere-centromere fusion (t telcen) with pseudodicentric structure. Most of these abnormalities were present in karyotypes with multiple alterations and associated to an evolutive stage of the disease (9 of 94 cases studied in progression, including three of 22 CML studied in blast crisis). The immunophenotype of the cell populations was lymphoid in eight cases, six of which were NHL, and myeloid, erythroid, and undifferentiated in the other three. More data on telomeric abnormalities may clarify whether there is ubiquitous genomic instability of neoplastic cells or an inborn cell lineage predisposition favoring rearrangements involving telomeres.

Assessment of minimal residual disease in acute promyelocytic leukaemia with t(15;17) by chromosome painting

To detect the minimal residual disease (MRD) in acute promyelocytic leukaemia patients treated with all-trans retinoic acid, we compared the sensitivity of metaphase fluorescence in situ hybridization (FISH) with conventional analysis of G-banded metaphases. 5 out of 6 patients studied at diagnosis showed the t(15;17) translocation. 4 out of 5 patients carrying t(15;17) achieved complete remission and conventional cytogenetic conversion. In 3 cases the whole chromosome painting (WCP) probe 17 discovered one normal chromosome 17 and two fragments indicative of t(15;17) persistence. The FISH-WCP technique seems to be highly sensitive and recommendable in monitoring leukaemias with specific chromosome rearrangements.

Detection of PML-RAR alpha fusion transcript in Ph positive leukemia with acute promyelocytic phenotype lacking the t(15;17) cytogenetic abnormality

A 39-year-old woman was diagnosed with acute promyelocytic leukemia (APL) with disseminated intravascular coagulation syndrome. The hematologic examination showed a morphologic, cytochemical, and immunophenotypic picture typical of an APL, with a marked leukocytosis and a mixed population of hypergranular and microgranular promyelocytes. The cytogenetic analysis showed a 46,XX,t(9;22) karyotype, without any alterations of chromosomes 15 and 17. The t(15;17) translocation was not evident in FISH experiments, while a molecular analysis revealed the presence of a PML-RAR alpha chimera.

Spontaneous loss of Ph chromosome with maintenance of clonal hemopoiesis in an untreated patient with myeloproliferative disease and a long survival

The unusual case of myeloproliferative disease described here is characterized by the following features: (1) a clinically completely silent course for 11 years without splenomegaly, marrow fibrosis, or cellular morphologic alterations; (2) the presence, at the onset, of a Philadelphia (Ph) chromosome without DNA breakpoints in the M-bcr region; (3) the spontaneous loss of detectable Ph-positive cells, 5 years after the first finding of leukocytosis, in the absence of any therapy; (4) the maintenance of the clonal nature of hematopoiesis, as revealed by the PGK X-linked inactivation pattern, in the absence of the Ph chromosome; and (5) a biphasic trend in the levels of leukocytes, red cells, and platelets during the years of observation.

Cytogenetic conversion in a case of polycythaemia vera treated with interferon-alpha

Polycythaemia vera is a clonal disorder of the haemopoietic stem cell causing a pathologic expansion of the erythroid and sometimes the megakaryocytic and myeloid elements. In order to avoid the possible mutagenic effects of radioactive phosphorus, alkylating agents and hydroxyurea, since 1988 alpha-IFN has been used for the treatment of PV and has been shown to induce and maintain haematological remission. We describe a 24-year-old PV patient with chromosomal abnormalities who achieved not only a reduction of the proliferation of erythroid elements and reticulin content in the bone marrow, but also a complete cytogenetic remission after IFN treatment.

Overexpression of c-kit in a leukemic cell population carrying a trisomy 4 and its relationship with the proliferative capacity

The expression of c-kit and its ligand, the stem cell factor (SCF), was studied in five cases of acute myeloid leukemia. One of these had a trisomy of chromosome 4, where the c-kit oncogene is located. In this case, the c-kit oncogene was overexpressed, but matched by a low expression of its ligand, SCF. The molecular evaluation of the growth rate by c-myc and the histone H3 expression indicated that the growth fraction of this cell population was very low. In one of the other leukemic cell populations studied, characterized by a low expression of c-kit and an elevated expression of the SCF, the growth fraction was also very low. Our results suggest that at least for some receptor oncogenes, the simple overexpression cannot be taken as an indication that the oncogene is involved in the deregulation of cell proliferation.

Progression of essential thrombocythemia to blastic crisis via idiopathic myelofibrosis

We report a 61-year-old man with essential thrombocythemia (ET) whose clinical course was followed for 12 years. The ET evolved into true idiopathic myelofibrosis (IM) 6 years after the initial diagnosis and progressed to myeloid blastic transformation 6 years later. The cytogenetic analysis showed a normal karyotype during the ET phase but subsequent analysis revealed an abnormal karyotype during the IM phase which evolved clonally at blastic crisis with constant involvement of chromosome 13q and chromosome 7. The close monitoring of essential events, using clinical, morphologic, immunologic and cytogenetic parameters, allowed us to carefully identify the transition from one chronic myeloproliferative disease (MPD) to another. This is only the second case reported showing a clinical evolution of this nature. The clinical and biological aspects of the disease are briefly discussed.

Sinus histiocytosis with massive lymphadenopathy

To date, the morphological aspects of sinus histiocytosis with massive lymphadenopathy (SHML) have been fully described. The disease is characterized by an enlargement of lymph nodes in which the sinuses are dilated and infiltrated by histiocytes, often phagocytosing lymphocytes. Even if the prognosis is usually benign and not requiring therapy, several fatal cases have been reported. The etiology is still obscure and the biology is not yet completely clear. Recent immunophenotypical studies suggest that histiocytes may belong to the T-zone associated histiocyte lineage. They may be cytologically homogeneous, but can express different antigenic patterns according to their stage of differentiation. Cytogenetic and molecular aspects of the disease have only been sporadically investigated. In order to better understand the pathogenesis of SHML, which seems to be a disorder lying in between the fields of infections, immunological disease and neoplasia, it is considered very useful to systematically employ a variety of immunophenotypical, cytogenetic and molecular techniques to study the disease, particularly in cases which are clinically atypical or with a more aggressive evolution.

Lymphocytes and low-frequency electromagnetic fields

Human lymphocytes have been used by several researchers to investigate the biological effect of electromagnetic fields (EMF). EMF modulate the response by lymphocytes to lectin stimulation. The size and direction of the effect depends both on the lymphocyte physiology and on the physical parameters characterizing the EMF. Lymphocytes have also been used to investigate the genotoxicity of EMF exposure.

Effect of low frequency low energy pulsing electromagnetic fields on mice injected with cyclophosphamide

C3H mice have been used to investigate the effect of a combination of cyclophosphamide (CY) and electromagnetic fields (PEMF). Mice were injected i.p. with a single dose of 200 mg/kg body weight of CY and then exposed to PEMF 24 h per day. In an initial series of experiments immediately after CY injection mice were exposed to PEMF until sacrifice. WBC counts in the peripheral blood demonstrated a quicker decline in WBC at days 1 and 2 in mice exposed to PEMF. Groups of mice were sacrificed at days 1, 4, 6, 8, and 10 after CY injection. In mice exposed to PEMF the spleen weight was less than in controls at days 6, 8, and 10. Autoradiographic studies demonstrated that the labeling index of bone marrow smears did not significantly differ between controls and experimental mice exposed to PEMF, whereas the spleen labeling index proved to be higher among control mice versus mice exposed to PEMF at day 6, and higher among mice exposed to PEMF versus controls at day 8. In a second series of experiments mice were exposed to PEMF only over the 24 h following CY injection. We found that the spleens of mice exposed to PEMF weighed less than those of controls at days 6 and 8. The labeling index of bone marrow did evidence a slight decrease among mice exposed to PEMF at days 8 and 10 after CY injection versus control mice. The spleen labeling index proved to be lower in experimental mice exposed to PEMF than in controls at days 4, 6, and 8. Mice were then injected with CY, half were exposed to PEMF, and 24 h later bone marrow was recovered from both groups of animals. The same number of bone marrow cells was injected via the tail vein into recipient mice irradiated to 8.5 Gy. The grafting efficiency of the bone marrow was evaluated by examining the number of spleen colonies and the spleen and bone marrow labeling indices at day 8; all parameters proved to be significantly lower among mice grafted with the bone marrow of mice injected with CY and exposed to PEMF than among controls injected with CY only. Finally, we found th at the effect of PEMF is evident only if mice are exposed during the 24 h following CY injection. The data reported here indicates that PEMF exposure after CY injection increases the damage induced in mice by CY.

Detection of low abundance mRNA of myeloid specific genes in cells of acute and chronic lymphoid leukemias by cRNA hybridization

The hybridization to a complementary RNA (cRNA) probe both in situ and in solution was used to assay tiny amounts of mRNA of the lactoferrin (LF) and myeloperoxidase (MPO) genes in normal bone marrow cells and in acute and chronic lymphoid leukemias. Evidence is reported that this technique is much more sensitive than the standard Northern blot technique. The LF mRNA was detectable in three of seven cases of acute lymphoblastic leukemia (ALL) and in three of seven cases of chronic lymphocytic leukemia (CLL). Four cases of ALL were also positive when tested with the MPO cRNA. It is apparent from these results that myeloid specific mRNA, different from MPO, may be detected in leukemic cells with lymphoid phenotype using a method more sensitive than the Northern blot technique. Whether or not the molecular events observed in these cell populations reflect events physiologically occurring rather than a deregulation of gene expression associated to leukemogenesis remains to be established.

Sinus histiocytosis with massive lymphadenopathy: immunological, cytogenetic and molecular studies

We describe a case of "sinus histiocytosis with massive lymphadenopathy" (SHML) studied by immunohistochemical, cytogenetic and molecular analysis. The immunophenotyping showed that the lymph node histiocytes were strongly positive for the S-100 protein and MoAb LeuM3, OKM5, KP1 and DRC-1; a portion of these cells was also positive for OKT6 and Leu3A, suggesting a possible relationship with the veiled cells, which represent an intermediate step in the pathway from the Langerhans cell to the interdigitating reticulum cell. Cytogenetic analysis showed a normal prevalent clone and a small hypodiploid clone and the molecular study showed no detectable involvement of the c-fms proto-oncogene, which is related to monocyte/macrophages. Unfortunately all these data do not seem sufficient to define the benign or neoplastic nature of the disease. Further investigations, immunophenotypical, cytogenetic and molecular, are needed to elucidate the pathogenesis of the disease, especially for more aggressive cases or for cases with unfavorable evolution.

Extramedullary pleural blast crisis in chronic myelogenous leukemia: cytogenetic and molecular study

Two patients with Ph1-positive chronic myelogenous leukemia with pleural blastic transformation occurring before medullary involvement are presented. The clonal origin of the pleural cells identified as unclassified blasts in 1 patient and as erythroid blasts in the other was confirmed by the presence of the t(9;22) translocation and their clonal evolution by the presence of duplicated Ph1 and additional chromosome alterations. DNA obtained from the pleural blasts and peripheral blood cells of 1 patient showed an identically rearranged bcr configuration, indicating the origin of the pleural blasts from the CML clone and suggesting that this genomic event is not directly linked with the progression of disease.

Overexpression of the MPO gene occurring in a case of APL without unusual genotypic characteristics

Northern blot analysis of four typical cases of acute promyelocytic leukemia showed that one of the cell population examined was characterized by a very high level of expression of the myeloperoxidase (MPO) gene. Western blot analysis confirms that the protein content of the cells corresponded to the levels of the MPO mRNA. Southern blot studies of the DNA of this cell population ruled out the presence of any genome amplification or rearrangement. Chromosome hybridization studies in situ confirmed that the MPO gene was translocated on the long arm of chromosome 15. The observation that a typical genomic pattern may or may not be associated with the MPO overexpression leads us to believe that so far it is impossible to reach any conclusion about the significance of the translocation in the genesis of MPO overexpression.

Philadelphia-positive chronic myelogenous leukemia with typical bcr/abl molecular features and atypical, prolonged survival

Despite the major breakthrough in the knowledge of the molecular events underlying the t(9;22) translocation, still no consistent data have been found on the evolution of Ph1 positive CML from the chronic to the accelerated or blastic phase of the disease. In most patients in fact the bcr/abl rearrangements are identical both in chronic phase and in blast crisis, and overall differences in chronic phase duration, related to different location of breakpoints inside the bcr region, were found to be marginal. We approached this problem by studying the molecular features of the bcr/abl abnormality in rare CML patients with very long, atypical chronic phase. The three patients studied, whose chronic phase duration is 17, 19, and 21 years, respectively, have typical genomic bcr rearrangements, and two of them show, hybridizing Northern blots to c-abl, the 8.5 kb mRNA, as that typically present in CML. It seems that genomic alterations within bcr and abl cannot account, alone, for the duration of the chronic phase of Ph1 positive CML and those quantitative and/or qualitative alterations of the p210 bcr/abl protein, unluckily awkward to prove, might be responsible for the atypical clinical features of these CML long survivors.

Expression of the myeloperoxidase gene in acute and chronic myeloid leukemias: relationship to the expression of cell cycle-related genes

The expression of the myeloperoxidase (MPO) gene was studied, by means of Northern blot analysis in 14 cases of acute myeloid leukemia (AML), 11 cases of chronic myeloid leukemia (CML), and 6 cases of CML blast crisis, and in HL60 cells before and after induction of terminal differentiation with retinoic acid (RA), phorbol esters (TPA), or vitamin D. The expression of a panel of cell cycle-related genes, namely C-MYC, histone H3, ornithine decarboxylase, P53, vimentin, and calcyclin, was also studied in the same cell populations. Our results indicate that: (a) MPO gene expression (steady state mRNA levels) is strictly confined to the first stages of myeloid differentiation, reaching its peak at the promyelocyte stage and becoming undetectable in mature granulocytes and monocytes; (b) cells devoid of any detectable MPO enzymatic activity such as leukemic basophils have a high content of MPO mRNA; and (c) MPO gene expression is not related to the growth activity of the cell population. Finally, our results show that the pattern of expression of growth-regulated genes in the neoplastic myeloid disorders AML, CML, and CML blast crisis is remarkably different.

Cytogenetic and molecular studies in primary myelofibrosis

Cytogenetic and molecular data of three patients affected by primary myelofibrosis with myeloid metaplasia (PMMM) evolving to blastic crisis are reported. The cytogenetic findings were uncommon. The first patient (female) showed an idic(X)(q13) as the sole alteration in chronic phase, with an additional r(7) in 67% of the cells of the blast crisis; the other two patients showed, in blast crisis, a partial trisomy of the long arm of chromosome 1, without translocation, as a unique structural abnormality. These findings confirm the presence of nonrandom, although nonspecific, alterations in PMMM that, in our cases, seem to be related to the multistep progression of the neoplastic process. Molecular investigations have been applied to study the genomic organization and the level of expression of genes such as bcr and calcyclin and c-fms protooncogene possibly involved in the molecular mechanisms underlying cell proliferation in hematopoietic cells. The data obtained are discussed with respect to the myeloproliferative disorder.