Coamplification of 12p11 and 12q13 approximately q22 in multiple ring chromosomes in a spindle cell sarcoma resolved by novel multicolor fluorescence in situ hybridization analysis

An 80-year-old male presented with a lobulated mass in the lower abdominal wall. A diagnosis of an intermediate grade myofibroblastic spindle cell sarcoma was made. Cytogenetic analysis demonstrated a complex karyotype with a der(6), a small marker and five, different in size, ring chromosomes. Fluorescence in situ hybridization (FISH), multiplex FISH, and multicolor banding analysis was used to further delineate this complex karyotype. The der(6) was shown to be a der(18)t(6;18;9;12;18), the marker chromosome was identified as del(17), and the ring chromosomes as r(9) and r(12;18)x4. Amplification of 18 and coamplification of 12p and 12q was detected in the ring and marker chromosomes. No intercellular heterogeneity was observed although a few micronuclei containing chromosome 18 and anaphase bridges, containing chromosome 12 material, the result of bridge-fusion-bridge (BFB) cycles, were observed. Our findings combined with results from others indicate that amplification of chromosomes 12 and 18 as well as BFB phenomena characterize this type of sarcoma.     

Jumping translocations of 11q in acute myeloid leukemia and 1q in follicular lymphoma

Jumping translocation is a rare cytogenetic aberration in leukemia and lymphoma, and its etiologic mechanisms are not clearly known. We report two cases with jumping translocations. One had follicular lymphoma and jumping translocations of 1q onto the telomeric regions of 5p, 9p, and 15q in three cell lines, co-existing with the specific translocation t(14;18)(q32;q21). The second case had acute myeloid leukemia (AML) and jumping translocations of 11q as the sole aberration, onto multiple derivative chromosomes in each of the abnormal cells. A total of 17 telomeric regions were seen as the recipients of 11q in this case, and 9q was always involved as one of the recipients in all abnormal cells. Fluorescence in situ hybridization (FISH) confirmed the identification of 11q material in the derivative chromosomes. While 1q has been the most common donor of acquired jumping translocations, this is the first report on jumping translocations of 11q. Different from all previously reported jumping translocations which involve only one recipient in each cell line and lead to a mosaic trisomy, multiple recipients in most of the abnormal cells in this case had led to a tetrasomy, or a pentasomy of 11q. The pattern of chromosome involvement as the recipients of 11q appears to show a continuing evolutionary process of jumping, stabilization, and spreading of the donor material into other chromosomes. Somatic recombinations between the interstitial telomeric or subtelomeric sequences of a derivative chromosome and the telomeric sequences of normal chromosomes are believed to be the underlying mechanism of jumping translocations and their clonal evolution.     

Two apparent Philadelphia chromosomes arising from translocations with different chromosomes in a patient with CML: 46,XY,t(7;22)(p22;q11),t(9;22)(q34;q11)

Chromosome studies on bone marrow cells and unstimulated peripheral lymphocytes from a patient with chronic myelogenous leukemia revealed the presence in all cells of two apparent Philadelphia chromosomes: one resulting from the classical translocation with a chromosome #9, and the other arising from a translocation between chromosomes #22 and #7. There was no normal chromosome #22. Some of the cells also had an i(17q), indicative of blast crisis. Repeated chromosome studies at different times during the course of the disease revealed the evolution of additional karyotypic changes. All cells from later samples had an extra #8; some of these cells had a third Philadelphia chromosome, whereas, others had a second Y chromosome. Although a few normal cells were seen in PHA-stimulated lymphocyte cultures, indicating that the patient has a normal constitutional karyotype, most of the cells had a karyotype identical to that found in unstimulated cultures. This unusual karyotype, 46,XY,t(7;22)(p22;q11),t(9;22)(q34;q11), represents the first case in which two apparent Philadelphia chromosomes are present in the leukemic cells from a patient in the absence of a normal #22 chromosome.     

Trisomy of the short arm of chromosome 8: Association with translocation between chromosomes 8 and 22 46,XY,22−,t(8p22q)+

The case of a retarded child with trisomy of the short arm of chromosome 8 associated with translocation between the short arm of chromosome 8 and the long arm of chromosome 22 is reported. Balanced translocation involving the same chromosomes was present in the mother and brother of the propositus. The specific chromosomes involved in the abnormality in this family were identified by use of fluorescence microscopy with quinacrine mustard staining, autoradiography and Giemsa banding. This appears to be the first case report of this anomaly, although trisomy of the short arm of chromosome 9 has been reported previously.     

Ring chromosome 7 with amplification of 7q sequences in a pediatric case of hepatosplenic T-cell lymphoma

Hepatosplenic T-cell lymphoma is rare, and most cases that have been reported with cytogenetic abnormalities have an isochromosome 7q with or without trisomy 8. A 7-year-old boy who had hepatomegaly and splenomegaly was diagnosed with hepatosplenic T-cell lymphoma on the basis of a bone marrow biopsy. The karyotype of the lymphoma cells at diagnosis included a ring chromosome 7 and trisomy 8. Fluorescence in situ hybridization analysis with chromosome 7 probes demonstrated amplification of a 7q31 sequence in the ring chromosome. While isochromosome 7q is a common abnormality in hepatosplenic T-cell lymphoma, and other structurally abnormal chromosomes 7 have been reported in a small number of cases, this is the first reported case of ring chromosome in hepatosplenic T-cell lymphoma.     

Recurrent breakpoints at 9q31 and 22q12.2 in extraskeletal myxoid chondrosarcoma

A cytogenetic study of extraskeletal myxoid chondrosarcoma cells revealed a complex t(9;22;15)(q31;q12.2;q25) as a primary chromosome change. A reciprocal translocation involving identical breakpoints on chromosomes #9 and #22 in this tumor has been reported in the literature. We suggest that the breakpoints 9q31 and 22.q12.2 are associated with extraskeletal myxoid chondrosarcoma, a comparatively rare tumor of adulthood.     

Osteoid osteomas with chromosome alterations involving 22q

Cytogenetic analysis was performed in two osteoid osteomas. In both, the modal chromosome number was 46. One of the cases presented a del(22)(q13.1) as the sole clonal chromosome alteration. The other had clonal monosomies of chromosomes 3, 6, 9, 17, 19, and 21, as well as a +del(22)(q13.1) was detected as a non-clonal chromosome alteration. There is only one osteoid osteoma reported so far showing clonal karyotypic alterations. The cytogenetic behavior of osteoid osteomas described here was different from that of the osteoid osteoma of the literature. Numerical alterations of chromosomes 3, 6, 9, 17, 19, 21 and 22 have been described in several neoplasias including bone tumors. The breakpoint of chromosome 22 involves a region where important genes for the regulation of the cell cycle have been mapped.     

Trisomy 1q in a patient with severe aplastic anemia

Aplastic anemia is a rare, serious disease characterized by hypocellular bone marrow and pancytopenia in the peripheral blood. Most cases are acquired, idiopathic, and without gross cytogenetic abnormalities. A few chromosome abnormalities have recurred among a small subset of patients, most commonly trisomy 8 and monosomy 7. Some of these chromosome abnormalities have prognostic and therapeutic significance, although for most the clinical relevance is not known. We present the case of a 40-year-old man with idiopathic severe aplastic anemia in bone marrow cells with trisomy of the whole long arm of chromosome 1 due to an unbalanced translocation between chromosomes 1 and 15 at breakpoints of q10 and 15q10. This clonal abnormality (which, to our knowledge, has not been previously reported in a patient with aplastic anemia) suggests that genes on 1q may be involved in marrow aplasia.     

Complex translocations between chromosomes #6, #9, #22, and #11 in a patient with chronic myelocytic leukemia: 46,XX,t(6;9;22;11)(p21;q34;q11;q13)

A case of chronic myelocytic leukemia with myelofibrosis has been reported. An abnormal clone with a rearrangement of four chromosomes: 46,XX,t(6;9;22;11)[p21;q34;q11;q13] was observed. The possible significance of this chromosome abnormality is discussed.     

Characterization of a complex translocation [t(4;9;22)(p16;q34;q11)] in chronic myelogenous leukemia by fluorescence in situ hybridization technique

A patient was referred with a high leukocyte count and diagnosed with chronic myelogenous leukemia (CML). Although practically asymptomatic since the time of diagnosis, he had a variable and inconsistent response to treatment. All of his bone marrow cells had a complex, three-way translocation, involving chromosomes 4, 9 and 22. Translocation of chromosome 4 to chromosome 9 was undetectable by routine cytogenetic techniques; however, by the fluorescence in situ hybridization technique, a three-way translocation was identified, 46,XYt(4;9;22)(p16;q34;q11). Although, other chromosomes are frequently involved in complex or variant translocations with chromosome 9 and 22, participation of chromosome 4 is a very rare event. So far, two previous cases have been described in the literature with translocations involving chromosome 4p16. We present a third case of CML having similar break points whose clinical presentation is unusual.     

Derivative (1;18)(q10;q10): a recurrent and novel unbalanced translocation involving 1q in myeloid disorders.

We report two cases of hematological malignancies, comprising a case of myelodysplastic syndrome (MDS) that rapidly evolved into acute myeloid leukemia, and a case of myeloproliferative disorder (MPD), in which der(1;18)(q10;q10) was found as the sole acquired karyotypic abnormality. This observation indicates that the unbalanced translocation is a recurrent aberration in myeloid disorders. To the best of our knowledge, centromeric fusion between long arms of chromosomes 1 and 18, leading to a normal chromosome 18 substituted with a der(1;18) chromosome, is novel and has not been described in cancer. Mechanistically, either trisomy 1q or monosomy 18p that results from the translocation may potentially contribute to leukemogenesis. Finally, chromosomes with large constitutive heterochromatin bands such as chromosome 1 may be at risk of centromeric instability and be predisposed to centromeric fusion with other chromosomes.     

Acute myeloid leukemia with t(5;18)(q35;q21).

A case of acute myelocytic leukemia with a translocation (5;18)(q35;q21) is reported. Cytogenetic abnormalities of the long arm of chromosome 5 have long been known to affect hematopoiesis. Although translocations between 5q and other chromosomes have been associated with malignancy, this is the first reported case of a t(5;18) resulting in acute myeloid leukemia. Possible molecular mechanisms underlying the pathogenesis of the disease are discussed.     

A de novo complex chromosomal rearrangement with a translocation 7;9 and 8q insertion in a male carrier with no infertility

A de novo complex chromosomal rearrangement (CCR) involving chromosomes 7, 8 and 9 in a male carrier was ascertained through his healthy wife's recurrent spontaneous abortions. Six pregnancies over eight years resulted in four spontaneous abortions and two livebirths who died perinatally due to abnormal vital signs. Cytogenetic analyses utilizing high resolution chromosome banding technique showed a deletion of band in a der(7) chromosome and an extra band inserting at 8q21.2. Another extra band was also observed at the band 9p24, but it could not be karyotypically determined. Fluorescent in-situ hybridization using chromosome 7 and 8 specific microdissected library as probes confirmed the insertion of a segment from the translocated chromosome 7 into a chromosome 8, and additionally revealed a translocation between chromosomes 7 and 9. The karyotype of the CCR carrier was determined as 46,XY,t(7;9)(q22;p24),ins(8;7)(q21.2;q22q32).ish der(9)(wcp7+);ins(8;7)(wcp8+,wcp7+). Comparing with previously reported male CCR carriers with our case, we conclude that male CCR carriers may not always present with infertility or subfertility phenotypes. This may suggest that rare transmission of male carriers could result from abnormal chromosomal rearrangements during meiosis and gametogenesis in addition to frequent infertility.     

Prenatal diagnosis of mosaic trisomy 8q studied by ultrasound, cytogenetics, and array-CGH

Mosaic trisomy 8, also known as Warkany syndrome, has a well-characterized constellation of phenotypic findings. Partial trisomy 8, including mosaic cases, has also been reported, with outcome and counseling dependent on the chromosomal segment involved and whether accompanied by partial aneuploidy for other chromosomes. We present a case of a fetus mosaic for trisomy of the entire long arm (q) of chromosome 8 without additional chromosomal aberrations. The diagnosis was made by amniocentesis performed following an 18 week sonogram that showed multiple fetal anomalies. Mosaicism for trisomy 8q was confirmed by routine karyotyping and fluorescent in situ hybridization (FISH) analysis. The case proved useful for testing the sensitivity of array comparative genomic hybridization (array-CGH) with respect to segmental trisomy in the presence of chromosomal mosaicism. The phenotype of this fetus, which appears to be the first reported case involving mosaic trisomy 8 for the entire q arm of the chromosome, is described and compared to previously reported cases involving partial trisomy 8q.     

De novo 46,XX, dir dup (11)(q13.3→q14.2) in a patient with mental retardation, congenital cardiopathy and thrombopenia

A 31-year-old female is reported with mild to moderate mental retardation, facial dysmorphy, congenital cardiopathy, and mild thrombocytopenia as the most important clinical findings. Chromosome analysis in lymphocytes showed a de novo dir dup (11)(q13.3→14.2), by both G-banding and FISH techniques. Previously reported constitutional duplications of 11q are mostly the result of unbalanced translocations involving chromosome 11q, and are associated with a partial monosomy or trisomy of the translocation partner chromosome. In case of an unbalanced translocation it is not clear which clinical findings result from the chromosome 11 duplication and which result from the abnormality on the translocation partner chromosome. This is the first report on a constitutional duplication of chromosome region 11q13.3→14.2 without involvement of other chromosomes.     

A cryptic unbalanced translocation t(2;9)(p25.2;q34.3) causes the phenotype of 9q subtelomeric deletion syndrome and additional exophthalmos and joint contractures

We report on a 26-year-old woman with microcephaly, typical facial features of 9q subtelomeric deletion syndrome, exophthalmos, contractures of elbow and knee joints, severe muscular hypotonia, no ability to walk, and no speech development.Array CGH revealed a cryptic 9q34.3 deletion and 2p25.2-p25.3 duplication transmitted by her mother, who was carrying a balanced translocation of chromosomes 2p and 9q. There are about 50 reported cases of deletions of the subtelomeric part of chromosome 9q, however, duplications of only the terminal part of chromosome 2p are rare. Neuroblastoma, diaphragmatic hernia, neural tube defects, broncho-pulmonary abnormalities, and congenital heart defects are conditions associated with partial trisomy of larger fragments of 2p. To our knowledge there is only one case described with an isolated duplication as distal as in the patient reported here. Joint contractures and exophthalmos observed in this patient are also seen in our patient. These features are not allegeable by the deletion 9q34.3 identified in the patient reported here and may be a hint that terminal duplication of 2p could be associated with exophthalmos and contractures.     

A case of childhood acute myeloid leukemia AML (M5) with a neocentric chromosome neo(1)(qter→q2324::q2324→q43→neo→q43→qter) and tetrasomy of chromosomes 8 and 21

Hyperdiploidy is rarely observed in childhood acute myeloid leukemia (AML). Described here is the case of a 2½-year-old girl with AML-M5 and 51 chromosomes characterized by double tetrasomy of chromosomes 8 and 21 and also a neocentric derivative chromosome neo(1)(qter→q2324::q2324→q43→neo→q43→qter). Little is known about the prognostic significance of these chromosomal abnormalities in childhood AML. In the actual case, complete remission was achieved after chemotherapy, which continued for 7 months. No acquired neocentric chromosome 1 has been described previously, even though neocentromere formation has been reported for other chromosomes in neoplasms.     

Isodicentric 20q- in two cases of B-cell acute lymphocytic leukemia with the respective t(9;20)(p11;q11.2) and t(9;22)(q34;q11.2)

The cytogenetic anomaly der(20)del(20)(q11.2q13.3)idic(20)(p11), or idic(20q-) in short form, has been reported in 13 cases of myelodysplastic syndrome, one case of chronic myelomonocytic leukemia, and one case of acute myeloid leukemia since 2004. To our knowledge, it has not previously been described in lymphoid diseases. Here we report the cases of two patients with B-cell acute lymphocytic leukemia (ALL) having a novel idic(20q-). One was a 34-year-old man with B-cell ALL whose leukemic cells at presentation had a karyotype of 45,XY,dic(9;20)(p11;q11.2); at relapse, a small marker chromosome was found coexisting with the dic(9;20). The other was a 39-year-old woman with Ph-positive B-cell-ALL whose leukemic cells contained both t(9;22)(q34;q11.2) and a small marker chromosome. A series of FISH analyses using the appropriate probes revealed the small marker chromosome in both patients to be an idic(20q-), confirming the dic(9;20)(p11;q11.2) in one case and revealing a BCR/ABL fusion gene in the other. One patient achieved complete remission but relapsed; the other did not achieve complete remission. Both patients died with a short survival time, despite receiving intensive chemotherapy. These two cases show that idic(20q-) can appear not only in myeloid diseases but also in lymphoid diseases.     

Nonmosaic smallest duplication of 12q24.31-qter: the first reported case

Duplication of the terminal region of the long arm of chromosome 12 is not common. In 13 previous cases, duplication of this region was generally associated with deletions of the derivative chromosomes, larger sized duplications or mosaicism. We have studied a young man with a nonmosaic duplication of 12q24.31-qter translocated to chromosome 5pter. This is the first reported case of pure subtle duplication involving less than two terminal subbands of 12q24.31 to qter. The origin of this genetic material was confirmed by whole chromosome paints and subtelomere specific FISH probes. As both the subtelomere signals for 5p and 12q were present in the der(5) chromosome, it is unlikely that there was any loss of unique DNA sequences from the terminal region of chromosome 5p. This case is compared with 13 other reported cases with a duplication of the 12q terminal segment.     

Duplication 9q34→qter identified by chromosome painting

We have studied an infant with multiple anomalies and a 46,XY,12p+ karyotype. Parental chromosomes were normal, and it was not possible to determine the identity of the extra material on chromosome 12 cytogenetically. Chromosome painting with probes from a chromosome 9 library identified this material as coming from chromosome 9, and cytogenetics established the duplication as 9q34→qter. Comparison of this patient with others reported with partial dup(9q) documented excellent concordance of minor anomalies, most notably dolichocephaly, “;deep-set”; eyes, short horizontal palpebral fissures, beaked nose, micrognathia, arachnodactyly, and developmental delay. Identification of cytogenetically indeterminate abnormalities by molecular cytogenetics is very important, as it permits prognosis to be offered for families of newborn infants with unbalanced karyo-types. © 1993 Wiley-Liss, Inc.