Tetrasomy 8 as a clonal anomaly in myeloid neoplasias

Tetrasomy 8 in a patient with chronic lymphocytic leukemia

We report a case of a 47-year-old man diagnosed with chronic lymphocytic leukemia (CLL) with two extra copies of chromosome 8. Classical cytogenetic analysis by the immunostimulatory combination of DSP30 and interleukin 2 showed tetrasomy of chromosome 8 in 60% of the metaphase cells (48,XY,+8,+8[12]/46,XY[8]). Spectral karyotype analysis confirmed the abnormality previously seen by G banding. Additionally, interphase fluorescence in situ hybridization using an LSI CEP 8 probe performed on peripheral blood cells without any stimulant agent showed tetrasomy of chromosome 8 in 54% of analyzed cells (108 of 200). To our knowledge, tetrasomy 8 as the sole chromosomal abnormality in CLL has not been previously described. The prognostic significance of tetrasomy 8 in CLL remains to be elucidated. However, the patient has been followed up in the outpatient hospital since 2004 without any therapeutic intervention and has so far remained stable.

Tetrasomy 8 in a patient with acute monoblastic leukemia

Trisomy 8 is one of the most frequent numerical chromosomal abnormalities observed in hematological malignancies, whereas tetrasomy 8 is a clonal aberration seen mainly in myeloid disorders such as acute myelod leukemia (AML) and myelodysplastic syndromes. In contrast to trisomy 8, tetrasomy 8 is a rare chromosomal aberration, in that only 17 reported AML cases with isolated tetrasomy 8 have been documented. Interestingly, the majority of reported cases were associated with monocytic-lineage leukemias. According to recent reports, tetrasomy 8 is regarded as a poor prognostic factor, and most patients having this abnormality relapsed and died within 1 yr. Here, we report a patient with acute monoblastic leukemia having tetrasomy 8 and a very aggressive disease course.

Acute myelogenous leukemia with tetrasomy 8 is a disease with a poor prognosis

Tetrasomy 8 is an extremely rare chromosome abnormality, one that has been reported in only a few cases with myeloid malignancies. The majority of reported cases consist of acute myelogenous leukemias (AML) of monocytic lineage. In slightly more than half of the patients, tetrasomy 8 was the single cytogenetic abnormality. Fluorescence in situ hybridization revealed tetrasomy 8 and trisomy 8 concurrently in all but one of the bone marrow samples. The clonal relationship between trisomy 8 and tetrasomy 8 in these cases remains to be clarified. Patients with tetrasomy 8 have a poor prognosis, and only 1 out of 33 patients was free of disease 3 years after autologous bone marrow transplantation. Here, we report the case of a 25-year-old female patient with monocytic leukemia and tetrasomy 8.

Polysomy 8 defines a clinico-cytogenetic entity representing a subset of myeloid hematologic malignancies associated with a poor prognosis: report on a cohort of 12 patients and review of 105 published cases

Tetrasomy, pentasomy, and hexasomy 8 (polysomy 8) are relatively rare compared to trisomy 8. Here we report on a series of 12 patients with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or myeloproliferative disorder (MPD) associated with polysomy 8 as detected by conventional cytogenetics and fluorescence in situ hybridization (FISH). In an attempt to better characterize the clinical and hematological profile of this cytogenetic entity, our data were combined with those of 105 published patients. Tetrasomy 8 was the most common presentation of polysomy 8. In 60.7% of patients, polysomy 8 occurred as part of complex changes (16.2% with 11q23 rearrangements). No cryptic MLL rearrangements were found in cases in which polysomy 8 was the only karyotypic change. Our study demonstrates the existence of a polysomy 8 syndrome, which represents a subtype of AML, MDS, and MPD characterized by a high incidence of secondary diseases, myelomonocytic or monocytic involvement in AML and poor overall survival (6 months). Age significantly reduced median survival, but associated cytogenetic abnormalities did not modify it. Cytogenetic results further demonstrate an in vitro preferential growth of the cells with a high level of aneuploidy suggesting a selective advantage for polysomy 8 cells.

Tetrasomy 8 as a primary chromosomal abnormality in a child with acute megakaryoblastic leukemia

Tetrasomy 8 is a relatively rare chromosomal abnormality in hematological disorders, and is mostly associated with myeloid malignancies and poor prognosis. In a number of cases, tetrasomy 8 has been reported as an accompanying anomaly with other chromosomal changes. In this report, we describe a 14-year-old girl with acute megakaryoblastic leukemia associated with tetrasomy 8 (primary) and trisomy 6, 19 and 20. She died 6 months after diagnosis, suggesting a relatively poor prognosis for AML with tetrasomy 8. To the best of our knowledge, this is the first report of a tetrasomy 8 abnormality associated with subtype FAB M7. Interestingly, this abnormality has not been previously reported in childhood AML patients.

Tetrasomy 8 is associated with a major cellular proliferative advantage and a poor prognosis. two cases of myeloid hematologic disorders and review of the literature

We report two cases of acute myeloid leukemia (AML) with tetrasomy 8 detected in patients' bone marrow samples using chromosome GTG-banding, fluorescence in situ hybridization (FISH) and primed in situ labeling (PRINS) techniques. Case 1 was a myelodysplastic syndrome (MDS) in transition to AML-M4 and case 2 was an AML-M2. In case 1, the tetrasomy 8 was found in 40% of metaphase cells and constituted the only chromosome abnormality. In case 2, it was accompanied by a double Ph, trisomy 18 and disomy Y and was found in 68% of metaphase cells. However, FISH and PRINS techniques revealed the coexistence of tetrasomy 8 and trisomy 8 in interphase nuclei of both cases. When the proportion of cells with tetrasomy 8 was compared between metaphases and interphase nuclei, it showed a much higher percentage of cells with tetrasomy 8 in metaphases than in interphase nuclei. Moreover, in case 2, although multi-PRINS and FISH-PRINS techniques showed other populations of interphase nuclei with different combinations of chromosome anomalies with respect to the copy numbers for chromosomes 8, 18, Y and Ph, only cells that contained either a single Ph or tetrasomy 8 plus trisomy 18, disomy Y, and double Ph could be seen in metaphases. This strongly suggests that tetrasomy 8 confers a higher proliferative advantage to cells. Our cases also show that the tetrasomy 8 is associated with a poor prognosis.

Clonal evolution from trisomy into tetrasomy of chromosome 8 associated with the development of acute myeloid leukemia from myelodysplastic syndrome

Tetrasomy 8, though rare, is usually associated with trisomy 8, a far more common chromosomal abnormality in acute myeloid leukemia (AML). Yet the clonal relationship between trisomy 8 and tetrasomy 8 in the cases with these chromosomal abnormalities has been unclear. Here, we report a case of a 17-year-old male, diagnosed as having a myelodysplastic syndrome (MDS). Chromosome analysis showed the presence of trisomy 8. Five years later, he developed overt AML exhibiting tetrasomy 8 only. After chemotherapy, the blast cells in the bone marrow decreased to 3.4%, and the karyotype showed trisomy 8 alone. Fluorescence in situ hybridization using a probe specific for chromosome 8 showed that the percentages of cells exhibiting 2/ 3 /4 signals were 7.8/89.2/2.0 at the MDS stage, 20.5/36.1/41.0 when overt AML developed and 24.0/72.1/2.4 after chemotherapy. These results suggested that tetrasomy 8 is derived from the AML clone, possibly evolved from the MDS clone with trisomy 8. To our knowledge, this is the first detailed case report of clonal evolution from trisomy 8 into tetrasomy 8 associated with the development of AML from MDS.

Trisomy/ tetrasomy of chromosome 8 and +i(8q) as the sole chromosome abnormality in three adult patients with myelomonocytic leukemia

We report three cases of tetrasomy 8 associated with myeloid disease. Two patients had chronic myelomonocytic leukemia (CMMoL) and the other had acute monocytic leukemia (AML M5 FAB). Two patients had trisomy/tetrasomy chromosome 8 as the sole abnormality. The other patient with CMMoL had two normal 8 chromosomes plus one isochromosome 8q; this is the first case of long arm chromosome 8 tetrasomy without short arm 8 monosomy. This cytogenetic finding suggests the importance of the genes located in the long arms of chromosome 8.

Pentasomy 8 in acute monoblastic leukemia

We report a case of pentasomy of chromosome 8 in 30-year-old man with de novo acute monoblastic leukemia (FAB AML M5a).

Translocation (15;17)(q22;q21) as a secondary chromosomal abnormality in a case of acute monoblastic leukemia with tetrasomy 8

We describe a case of acute monoblastic leukemia (AML M5a), originally presenting as granulocytic sarcoma of the testis, showing unusual cytogenetic abnormalities. Tetrasomy 8 (primary) and t(15;17)(q22;q21) (secondary) were detected in bone marrow cells 6 months post-diagnosis, both by routine karyotype analysis and by fluorescence in situ hybridization (FISH) studies on metaphases and interphase nuclei. Retrospectively, the same abnormalities were identified in the primary testicular lesion using interphase FISH. However, reverse transcriptase polymerase chain reaction (RT-PCR) did not reveal the presence of a classic PML/RAR alpha fusion transcript. To the best of our knowledge, this is the first case to be reported in the literature of AML showing tetrasomy 8 in combination with secondary t(15;17).

Isolated tetrasomy 8 in minimally differentiated acute myeloid leukemia (AML-M0)

Tetrasomy 8 as a sole anomaly in hematological disorders is relatively rare. To the best of our knowledge, only 19 such cases have been described in the literature to date. Of them, acute myeloid leukemia (AML) in 13 (M1, one; M2, three; M4, one; M5, eight), acute lymphoblastic leukemia(ALL) in one, myelodysplastic syndrome(MDS) in 3, polycythemia vera(PV) and myelofibrosis(MF), one case each. Their median survival was 20 weeks. Here, we report the first case of a 29-year-old man with minimally differentiated AML (AML-M0) displaying a tetrasomy 8 clone. Immunophenotyping showed positivity with CD33, CD34 and intracellular MPO, but all lymphoid markers tested were negative. Conventional cytogenetics of bone marrow cells showed 84.9% of metaphases with tetrasomy 8 in addition to 15.1% with normal diploidy. However, Fluorescence in situ hybridization(FISH) using a centromeric probe specific for chromosome 8 revealed trisomy 8 in 14.2% of interphase nuclei besides tetrasomy 8 in 82.4%. The patient died four weeks after diagnosis without therapy. In conclusion, these findings suggest that tetrasomy 8 is associated with a heterogeneous group of myeloid disorders and heralds a bad prognosis. It may be a consequence of clonal evolution of trisomy 8.

A second case of hexasomy 8 in myelodysplastic syndrome

Tetrasomy 8 is a rare form of acquired aneuploidy found exclusively in the myeloid leukemias. Hexasomy 8 is even rarer: only one case has been reported, thus far. We describe here the second case of hexasomy 8 as the sole abnormality in an elderly female patient with myelodysplastic syndrome (MDS).

Chromosome 8 tetrasomies and pentasomies--a clonal abnormality closely associated with acute monocytic leukaemia

We report four cases of polysomy 8 (one tetrasomy and three pentasomies) observed in acute monocytic leukemia (FAB M4 and M5). Three of them showed a rearrangement of 11q23 identified by conventional cytogenetic analysis and/or chromosome painting. Our cases as well as a review of the literature, suggest that polysomy 8 is preferentially associated with monocytic differentiation (24/31). These polysomies have been observed in 21 de novo leukemias and in 10 secondary hematological disorders. A 11q23 rearrangement has been detected in 9 out of 32 patients, by conventional cytogenetic techniques in 7 and by FISH in 2. We suggest that these cases should be analysed by FISH and molecular studies in order to detect a rearrangement of MLL/11q23. Monocytic differentiation is often associated with a change of the MLL gene and the polysomy 8 might be a particular clonal evolution secondary to 11q23 abnormality.

Coexistence of tetrasomy 8 and trisomy 8 in a case with myeloid metaplasia with myelofibrosis

We present a case of myeloid metaplasia with myelofibrosis (MM/MF), with tetrasomy 8 as the sole cytogenetic abnormality detected by conventional cytogenetic studies. Tetrasomy 8 was also detected by in situ interphase studies and confirmed by chromosome painting in metaphase. To our knowledge, this is the first case of MM/MF with tetrasomy 8. Noteworthy is the association with neurofibromatosis.

Tetrasomy 8 detected by interphase cytogenetics in a child with acute lymphocytic leukemia

Tetrasomy 8 is a rare clonal anomaly in human acute leukemia. Here we present a case of a 7-year-old boy with acute lymphoblastic leukemia (ALL) displaying a tetrasomy 8 clone that could not be detected by conventional cytogenetics. In this study, bone marrow and peripheral blood cells were collected at five different diagnostic stages and analyzed by double targeted fluorescence in situ hybridization (FISH) with centromeric DNA probes for chromosomes 7, 8, 9, and 12. FISH analysis revealed a significant increase in tetrasomy 8 frequency, but not in other chromosomes examined. A smaller increase in trisomy 8 was also detected. At one stage over 60% of the cells were hyperdiploid with 40% being tetrasomic. The size of the tetrasomic clone changed during the course of the disease. The hyperdiploid frequencies of chromosome 8 detected by interphase FISH analysis in bone marrow and peripheral blood were similar. Our findings indicate the utility of FISH analysis in cytogenetic monitoring of leukemia patients and further show that tetrasomy 8 may play a specific role in a subtype of ALL.

Tetrasomy 8 in a patient with acute nonlymphocytic leukemia: a metaphase and interphase study with fluorescence in situ hybridization

Tetrasomy 8 constitutes a relatively rare recurring chromosome defect in myeloid disorders. The patient reported here, a 71-year-old man, presented with tetrasomy 8 as the sole chromosome abnormality associated with an acute nonlymphocytic leukemia of the M2 type. He failed to respond to chemotherapy and died one year after diagnosis. Following conventional cytogenetics and fluorescence in situ hybridization (FISH) with a centromeric probe specific for chromosome 8, tetrasomy 8 was detected in 61% of the metaphases analyzed and trisomy 8 in 39%. FISH analysis of interphase nuclei confirmed the existence of tetrasomic (35%) and trisomic cells (56%) and revealed a number of cells with two chromosomes 8 (8%). This normal population may represent lymphocytes or myeloid cells that escaped conventional analysis due to their inability to divide or to the small number of metaphases available. The relatively higher proportion of tetrasomic cells in metaphase compared with interphase may be attributed to a proliferative advantage of tetrasomic cells in vitro or to the longer duration of their cell cycle. The simultaneous presence of trisomic and tetrasomic cells confirms the hypothesis of a clonal relationship between trisomy 8 and tetrasomy 8. Our case brings further evidence to the specificity of tetrasomy 8 to myeloid disorders and to the association of this chromosome abnormality with a relatively poor prognosis. However, new patients must be studied to further delineate this cytogenetic entity.

Tetrasomy 8 and t(1;11)(p32;q24) in acute myelo-monocytic leukemia with extensive leukemic cutaneous involvement

We report a case of tetrasomy 8 in a patient suffering from acute myelomonocytic leukemia with extensive leukemic cutaneous infiltration. In all metaphases analyzed t( I;11)(p32;q24) was concomitantly observed. Similarly to other cases with tetrasomy 8, the patient showed monocytic involvement and poor response to chemotherapy. We conclude that this kind of cytogenetic aberration is associated with distinct morphologic and clinical features.

Double isochromosome 8q as single cytogenetic aberration in acute myelo-monocytic leukemia

We report a case of double isochromosome 8q as a single cytogenetic abnormality in a patient with acute myelo-monocytic leukemia. Similarly to rare cases with tetrasomy 8, the patient showed monocytic involvement and was refractory to cytotoxic chemotherapy. We conclude that this kind of cytogenetic aberration is probably associated with distinct morphologic and clinical characteristics.

Tetrasomy of chromosome 8 in a patient with acute myeloid leukemia

We report a case of acute myeloid leukaemia (AML), FAB classification M2, associated with tetrasomy 8. This chromosomal aberration was detected using conventional cytogenetics and flourescent in-situ hybridization (FISH). Using FISH, the pre-treatment cells with tetrasomy 8 were disomic for chromosome 7. A small number of tetrasomy 8 cells were found post-treatment, but these were tetrasomic for chromosome 7. The significance of this is considered, and the literature regarding tetrasomy 8 in acute myeloid leukaemia is reviewed.