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N Mandahl

Publications and source records attributed to N Mandahl.

At least 217 records · Page 12Linked to original sources
PubMed1991

Chromosomal abnormalities in giant cell tumors of bone.

Cytogenetic analysis of short-term cultures from ten giant cell tumors of bone revealed clonal and nonclonal chromosome abnormalities in three tumors and nonclonal changes only in seven. None of the clonal aberrations, inv(21)(p11q21) in one tumor, +5 in another, and t(15q22q), dic(4;22)(p16;p1?), double minutes, dicentrics, and ring chromosomes present in three separate clones in the third tumor, were identical to previously reported clonal changes in giant cell tumors. Telomeric associations were found in five tumors. The telomeres of chromosome arms 19q and 15p were particularly frequently involved.

Adolescent↗
PubMed1991

Chromosome analysis of 96 uterine leiomyomas.

From September 1989 to May 1990, we attempted cytogenetic analysis on 96 uterine leiomyomas removed from 64 women. Of the 90 tumors in which analysis was successful, 59 had a normal karyotype while 31 had clonal abnormalities. The most common aberration (13 tumors) was 7q-, mostly del(7)(q21.2q31.2); in two tumors with +12 and t(12;14) as the primary abnormalities, the 7q- was obviously a secondary change since it was found only in a subclone. A t(12;14)(q14-15;q23-24) was detected in two tumors, complex aberrations involving both 12q14-15 and 14q23-24 were also present in two, and rearrangements of 12q without concomitant 14q changes were seen in another two myomas. Rearrangements of 6p were present in five tumors, and trisomy 12 was found in two. More than one abnormality could be detected in 17 leiomyomas. Evidence of clonal evolution in the form of subclones was found in eight tumors, all of which were cellular and had histologically detectable mitotic activity. In addition to their clonal complexity, these myomas also frequently exhibited clonal telomeric associations (four tumors) and ring chromosome formation (three tumors; twice affecting chromosome 1). Monosomy 22 occurred as a secondary abnormality in three tumors; it, too, may reflect a preferred pathway in the karyotypic evolution of uterine leiomyomas.

Chromosome Aberrations↗
PubMed1991

Chromosomal abnormality t(9;22)(q22;q12) in an extraskeletal myxoid chondrosarcoma characterized by fine needle aspiration cytology, electron microscopy, immunohistochemistry and DNA flow cytometry.

A multidisciplinary approach was taken to characterize a soft tissue tumour. In smears prepared from aspirated material, uniform tumour cells, embedded in a myxoid matrix and partly arranged in a lace-like pattern, were found. Histopathology showed a lace-like pattern of cells in a matrix of hyaluronidase-stable mucins. Cytoplasmic positivity for S-100 protein was found in some tumour cells. Electron microscopic analysis revealed intracisternal aggregates of microtubules. All these features are consistent with the diagnosis of extraskeletal myxoid chondrosarcoma (EMC). DNA flow cytometry showed a diploid DNA content. Cytogenetic examination revealed the tumour karyotype 45,XY,t(2;11)(q31;p15),t(9;22)(q22.3;q12),dic(13;22)(p11;p13). Because similar 9;22-translocations have been described in two other cases of EMC, we conclude that t(9;22)(q22-31;q11-12) is a specific rearrangement in this tumour type. Cytogenetic analysis may thus be of diagnostic value in the examination of tumours with this and similar histologies.

Aged↗
PubMed1990

On the significance of trisomy 7 and sex chromosome loss in renal cell carcinoma.

Cytogenetic analysis of 30 renal cell carcinomas showed 3p aberrations in nine tumors, trisomy 7 in 17 tumors, and clonal loss of one sex chromosome in 14 tumors. The 3p aberrations and trisomy 7 were present in the same clone in two tumors and in separate clones in three tumors. Loss of one sex chromosome was present together with 3p aberrations in the same clone in one tumor and occurred in seemingly unrelated clones in two tumors. It occurred as the sole change in five tumors. Clones with trisomy 7 as the only change were present in six tumors. Trisomy 7 and loss of one sex chromosome were present in separate clones in four tumors and in the same clone in one tumor. Because +7 and -X/-Y were thus rarely present together with clonal structural abnormalities, in particular 3p changes, our findings make it highly unlikely that loss of one sex chromosome or trisomy 7 represents a primary change in renal cell carcinoma. We instead suggest that there is a tendency for normal kidney cells to lose an X or a Y chromosome and also to gain an extra copy of chromosome 7. This tendency is retained by renal carcinoma cells; therefore, trisomy 7 and sex chromosome loss should not be viewed as tumor-specific abnormalities in this context. Whether these simple numerical aberrations reflect in vivo mosaicism or are acquired in vitro remains unresolved.

Adult↗
PubMed1990

Simple numerical chromosome aberrations in well-differentiated malignant epithelial tumors.

Cytogenetic analysis of four well-differentiated malignant epithelial tumors revealed primary clones with only numerical abnormalities. The karyotypes were 49,XX, +5, +5, +7, +7, -17/50,XX, +5, +5, +7, +7, -17, +r in an adenocarcinoma of the lung; 47,XX, +3/47,XX, +5/47,XX, +7 in a squamous cell carcinoma of the epiglottis; 47,XX, +5/48,XX, +5, +10 in a squamous cell carcinoma developing in an ovarian dermoid cyst; and 52,XX, +5, +7, +8, +14, +15, +21 in a seropapillary ovarian adenocarcinoma. Also, in previously published cases exclusively numerical aberrations were much more common in highly differentiated epithelial tumors (22/74) than in moderately to low-differentiated carcinomas (13/281). Our findings and the literature data thus agree with a developmental scheme in which numerical changes, possibly reflecting an early-onset genomic instability in the tumor cells, may precede massive structural anomalies in the gradual malignization of epithelial tumors.

Adenocarcinoma↗
PubMed1990

Localization of the chromosomal breakpoints of the t(12;16) in liposarcoma to subbands 12q13.3 and 16p11.2.

Short-term cultures of two myxoid liposarcomas and two mixed-type (myxoid and round cell) liposarcomas were cytogenetically analyzed. A t(12;16)(q13;p11) was present in three tumors, whereas the fourth had an unbalanced 12;16-translocation with breaks in 12q13 and 12q22, with loss of the 12q13-q22 segment, and in 16p11. In the two mixed liposarcomas, the breakpoints could be determined at subband level to 12q13.3 and 16p11.2.

Adult↗
PubMed1990

Cytogenetic findings in acute megakaryoblastic leukemia (ANLL-M7).

The clinical, morphologic, and cytogenetic findings in a patient with acute megakaryoblastic leukemia (ANLL-M7) are described. At the time of diagnosis, the karyotype contained three related clones: 47,XY,t(3;6)(p13;q27), +8,t(12;22)(p13;q12), +15, -21, -22, +der(22)t(21;22)(q11;p13)/47,XY, +8,del(9)(q22),t(12;22), +15, -21, -22, +der(22)/46,XY, +8, t(12;22), -21, -22, +der(22). Complete remission was achieved with intensive combination chemotherapy. At relapse 20 months later, there was clear evidence of clonal evolution, and the karyotype was now 45,XY,t(2;18)(q33;p11),del(9)(q22),t(12;22)(p13;q12), -16, +der(16)t(8;16)(q13;p13), -21, -22, +der(22)t(21;22)(q11;p13)/46,XY,t(2;18),del(9),t(12;22), -16, +der(16), -21, -22, +der(22), +mar. A comparison with the few previously cytogenetically analyzed cases of ANLL-M7 reveals that structural rearrangements of chromosomes 21 and 22 might be of primary importance in the pathogenesis of acute megakaryoblastic leukemia.

Adult↗
PubMed1990

Chromosomal rearrangements in chondromatous tumors.

Short-term cultures from 16 chondromatous tumors, 15 primary and one recurrent, were analyzed cytogenetically. Clonal chromosome aberrations were found in one of six benign tumors and in seven of ten malignant tumors. A chondroma had a complex translocation involving chromosomes X, 8, 12, and 13, as well as a deletion of the derivative chromosome 8. In the malignant tumors, monosomy 6 and 22 were observed in three tumors and monosomy 10, 11, 13, and 18 were observed in two tumors. In two of the three metastasizing tumors, del(5) (q13) and loss of chromosomes 6, 10, 11, 13, and 22 were common features. Structural aberrations of chromosome 1 were found in five tumors, of chromosomes 6, 12, and 15 in three tumors, and of chromosomes 4, 5, 9, and 20 in two tumors. We conclude that although considerable cytogenetic heterogeneity exists among chondromatous tumors, the karyotypic anomalies are still nonrandom.

Adolescent↗
PubMed1990

Trisomy 21 in neoplastic cells.

Trisomy 21 as an acquired clonal chromosome change has been described in 642 of the 10,625 human neoplasms with chromosome aberrations known from the cytogenetic literature. A total of 590 of the 642 cases (92%) are hematologic disorders and malignant lymphomas. The incidence of trisomy 21 is similar (4.1%-6.7%) in acute myeloid leukemia (AML), chronic myeloid leukemia, myeloproliferative disorders, myelodysplastic syndromes, chronic lymphoproliferative disorders, and malignant lymphomas; it is substantially higher (14.8%) in acute lymphocytic leukemia (ALL). In most cases, the extra chromosome 21 is present together with other numerical and/or structural changes. Acquired trisomy 21 is the only karyotypic abnormality in only 0.4%. Trisomy 21 has never been reported as the sole anomaly in a solid tumor. The cytogenetic literature contains information on 62 patients with constitutional trisomy 21 and a malignant disorder in which the tumor cells have been analyzed by banding techniques. Thirty-four of the 62 patients had AML, 16 had ALL, and 2 had acute undifferentiated leukemia. The 52 leukemic Down syndrome (DS) cases account for 1.4% of the total acute leukemias, an overrepresentation that parallels the generally increased risk of leukemia development in DS. Sixty-three percent of the ALL patients and 79% of those with AML had additional changes superimposed on constitutional trisomy 21. These included several of the characteristic primary leukemia-associated aberrations: 5q-, 7q-, +8, and t(8;21) in AML, and t(1;19), t(4;11), 6q-, and 14q + in ALL. Thus, it seems that the pattern of acquired karyotypic changes is similar in patients with DS and in individuals with a normal constitutional karyotype.

Chromosome Aberrations↗
PubMed1990

Unrelated clonal chromosomal aberrations in carcinomas of the oral cavity.

Short-term cultures from 12 oral squamous cell carcinomas were cytogenetically investigated. A normal karyotype was found in 3 tumors, 2 of which had many nonclonal changes. Clonal chromosome abnormalities were detected in the remaining 9 cases, in 6 of them in the form of 2 or 3 abnormal clones. In 5 cases the different clones were cytogenetically unrelated, suggesting a multiclonal origin. Numerous additional nonclonal changes were present in 4 of the 9 tumors with clonal aberrations. None of the structural aberrations, clonal or nonclonal, were found in more than one case; nor did any of the rearrangements correspond to cancer-associated aberrations known from other tumors. The aberration breakpoints of the present series and of previously reported tongue cancer clustered to bands 1p32, 1p22, 1p11, 1q21, 1q23, 1q25, 1q32, 1q42, 1q44, 2q31, 3p11, 4q35, 7p22, 11p15, 11q13, 12q24, and 17q25.

Aged↗
PubMed1990

Trisomy 12 is a consistent chromosomal aberration in benign ovarian tumors.

Clonal karyotypic abnormalities were detected in 7 of 42 cytogenetically analyzed benign ovarian tumors. An adenofibroma had -X and a mucinous cystadenoma had t(1;11)(q25;q23) as the sole abnormality. Trisomy 12 was found in the remaining five tumors. It was the only change in two fibromas and a serous cystadenoma; the fourth tumor, a mucinous cystadenoma, had one clone with +12 and one with +12 and +10, and the fifth tumor, a fibrothecoma, had +4,+9,+12. The finding of trisomy 12 in five of seven karyotypically aberrant tumors suggests that this aberration characterizes a hitherto unrecognized cytogenetic subgroup of benign ovarian neoplasms.

Adenofibroma↗
PubMed1990

Frequent rearrangement of chromosomal bands 1p22 and 11q13 in squamous cell carcinomas of the head and neck.

We report the finding of clonal structural chromosome abnormalities in short-term cultures from 15 squamous cell carcinomas of the head and neck region. When the distribution of chromosomal breakpoints in these 15 tumors and in the 16 head and neck carcinomas previously described are assessed, a marked clustering is seen at bands 1p22 and 11q13, which are rearranged in eight and nine tumors, respectively. No other band was involved in aberrations in more than five tumors. Cytogenetic evidence of gene amplification was seen in four tumors, three times in the form of homogeneously staining regions (twice located in 11q13), and in one tumor as double minutes. Among the candidate genes for such amplification are BCLI, INT2, and HSTI, all of which map to 11q13, and NRAS, which maps to 1p22. All these oncogenes have previously been shown to be amplified in subsets of head and neck carcinomas. We conclude that bands 1p22 and 11q13 are nonrandomly involved in chromosomal rearrangements in head and neck carcinomas and suggest that activation of oncogenes located in these bands may proceed via cytogenetic mechanisms.

Aged↗
PubMed1990

High resolution mapping of consistent leiomyoma breakpoints in chromosomes 12 and 14 to 12q15 and 14q24.1.

A substantial percentage of uterine leiomyomas are cytogenetically characterized by consistent, clonal chromosome abnormalities, including t(12;14)(q14-15;q23-24) and other rearrangements of 12q14-15 that occur without any visible 14q changes. The partly similar banding characteristics of these two regions have hitherto precluded exact mapping of the 12q and 14q breakpoints to any particular band, let alone their assignment to subbands. In the series of four myomas presented here, in which one tumor had inv(12q), two t(12;14), and one a three-way t(7;12;14), we were able to achieve high resolution banding (550 band stage) of the rearranged chromosomes in several metaphases. This enabled us to assign a 12q breakpoint to 12q15 in all tumors and, in the three cases informative in this regard, the 14q breakpoint to 14q24.1. The more precise breakpoint mapping considerably narrows down the area that must be examined with molecular genetic methods in order to identify the gene loci that are rearranged in leiomyomas with 12q and 14q aberrations. It will also help determine to what extent leiomyoma rearrangements of 12q involve the same loci that are affected in 12q changes in other tumor types, e.g., in pleomorphic adenomas of the salivary gland, in lipomas, and in myxoid liposarcomas. At present it seems that the breakpoint in 12q may be cytogenetically identical in the three benign tumors, whereas it in myxoid liposarcomas appears to be more proximal.

Chromosome Aberrations↗
PubMed1990

Malignant fibrous histiocytomas with a 19p+ marker chromosome have increased relapse rate.

Malignant fibrous histiocytomas (MFH) often have complex karyotypic abnormalities. Recently, we described a 19p+ marker chromosome in 9 of 22 MFH. Other recurrent karyotypic features have been telomeric associations, ring chromosomes, and structural rearrangements of chromosomal bands 1q11, 3p12, and 11p11. After a median follow-up time of 18 months, distant metastases and/or local recurrence have occurred in 8 of the 9 patients with 19p+ markers but in only 4 of the 13 patients without. The only other cytogenetic parameter that seemed to affect relapse tendency was the presence of ring markers: relapse has occurred in 2 of 8 patients with unidentifiable supernumerary ring marker chromosomes compared to 10 of 14 patients without. No differences in relapse frequency were apparent for tumors belonging to the other cytogenetic subgroups. It thus appears that 19p+ marker chromosomes in MFH signal an increased relapse risk whereas the finding of ring markers indicates a reduced relapse risk.

Adult↗
PubMed1990

Parallel karyotypic evolution and tumor progression in uterine leiomyoma.

Cytogenetic evidence of clonal evolution was detected in five uterine leiomyomas. In two tumors, two clones were found, the third tumor had four, the fourth had nine, and the fifth had 12 clones. The first tumor had trisomy 12 as the primary anomaly and a sideline that also contained a del(7)(q21q31). Both clones of the second tumor had three structural changes in common but differed by the presence in the more advanced clone of an inv(7)(q31q34). Two cytogenetically unrelated pairs of clones were seen in the third tumor. One clone had a stemline of 46 and an r(1); a sideline had developed through duplication of this clone. The other pair had a del(7)(q21q31) in common. The last two tumors both had t(12;14)(q14-15;q23-24) as the primary abnormality. They also had a high frequency of telomeric associations that involved certain chromosome arms only. One of the secondary changes in the fourth tumor was a del(7)(q21q31); the principal secondary change in the fifth case was a ring chromosome 1 of variable size in the different clones. The analysis of these five uterine leiomyomas and the collation of the results with previously obtained data lead us to conclude that del(7)(q21q31) is secondary to t(12;14) and + 12 in this tumor type, and that ring formation involving chromosome 1 material, often with duplication of segments, is a common phenomenon during clonal evolution. The fact that the tumors were classified as cellular and had an increased mitotic rate indicates a parallel development between histologically detectable tumor progression and cytogenetically recognizable clonal evolution in uterine leiomyomas.

Chromosome Aberrations↗