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The phenotypic progression of colorectal tumors is driven by their step-by-step acquisition of genomic alterations. These pathogenetically important mutations are at the same time markers of tumor clonality. The aim of this study was to describe the clonal relation among synchronous colorectal adenomas. Twenty-four colorectal adenomas from 11 patients were subjected to chromosome banding analysis. Clonal chromosome abnormalities were found in 20 tumors. Recurrent structural rearrangements involved chromosomes 1, 13, 17, and 18. The most common numerical changes were gain of chromosomes 7, 13, 20, and 3 and loss of chromosome 18. Eight adenomas had subclones as evidence of clonal evolution. Similar clones in separate polyps were seen in tumors from 6 patients; these adenomas were always located in the same part of the large bowel. In 2 patients, both with one rectal adenoma and one adenoma in the colon, no karyotypic similarity between the lesions was found. Our findings indicate that whereas close, but macroscopically distinct, synchronous colorectal adenomas usually have a common pathway of progression, perhaps even the same clonal origin, large bowel adenomas at a considerable distance from one another exhibit karyotypic differences, indicating that they arise independently.

To better understand the role of trisomy 8 in myelodysplastic syndrome (MDS), we performed a multiparameter analysis combining conventional chromosome studies (CCS), fluorescence in situ hybridization (FISH), and bone marrow (BM) culture studies in two patients with MDS evolving into acute myeloid leukemia (AML). A mosaicism of a cytogenetically normal clone and a clone with trisomy 8 was detected in both patients throughout the course of the disease, a finding confirmed by FISH on BM cells. The relative size of the trisomic clone increased from 52% to 71% (p Combined FISH and immunophenotyping of BM cells showed involvement of the granulomonocytic lineage in patient 1 and involvement of erythroid cells as well as of the granulomonocytic lineage in patient 2. Only disomic lymphocytes were detected in both patients. FISH on single hemopoietic colonies grown in semisolid media detected trisomic CFU-GM and disomic BFU-E in patient 1, whereas a proportion of CFU-GM and BFU-E deriving from the trisomic clone was detected in patient 2. However, the percent of trisomic colonies was lower than the percent of involved granulomonocyte precursors and involved erythroblasts, as detected by combined FISH and immunophenotyping on fresh BM samples. We have thus shown heterogeneity of lineage involvement by trisomy 8 in MDS undergoing transformation into AML. Although preferential growth of disomic clones may occur in vitro, the finding of an increased size of the trisomic clone at the time of leukemic switch suggests that these cells had proliferative advantage in vivo over cells without trisomy 8.

Epithelioid leiomyomas of the uterus, unlike ordinary leiomyomas, show substantial epithelial differentiation. No chromosome abnormalities have been reported in uterine epithelioid leiomyomas before. We analyzed short-term cultures from five such tumors and detected abnormal karyotypes in four. A del(7) (q21.2q31.2) was found in two tumors, in one as the only change and in the other as a secondary aberration acquired during clonal evolution. Rearrangement of chromosomal band 12815, another of the cytogenetic hallmarks of ordinary uterine leiomyomas, was seen in the form of a t(10;12) in one tumor. Band 17q21 was involved in structural aberrations in two cases. The data we present indicate that epithelioid leiomyomas are fundamentally similar cytogenetically, and hence presumably also pathogenetically, to the much more common smooth muscle-differentiated uterine myomas. The only differences hinted at are that epithelioid tumors may be karyotypically more complex and more often have rearrangements of 17q21.

Scientific methods and models are interdependent. That the techniques one uses determine which findings one gets, is evident. But equally important is the influence of our a priori expectations; they may cause us to choose inadvertently those methods that are most likely to yield results that appear to confirm an already preconceived picture of reality. The conceptual models and methods of solid tumor cytogenetics are to a large extent inherited from leukemia and lymphoma cytogenetics. We illustrate how this may bias the generation and interpretation of new findings, especially when carcinomas are investigated. These malignant epithelial tumors much more often harbor cytogenetically unrelated clones than do hematologic or mesenchymal neoplasms. Carcinoma cytogenetics is therefore extremely susceptible to selection differences, making the results heavily dependent on which sample is processed, how it is disaggregated, how and for how long the cells are cultured, and on how the analysis is performed and the results presented. This calls for more efforts to be directed toward establishing also the phenotypic nature of those cells that are being karyotyped. As one cannot yet quality-grade most clonal chromosome changes in any reliable manner, meaning that one cannot determine to what extent each aberration or each clone contributes to the neoplastic process, statements about the "true" karyotypes of tumor parenchymas should be viewed with suspicion. A complete carcinoma karyotype may be much more complex than extrapolations from the analysis of a few cells may lead one to believe.

A cell line was established from a liver metastasis of a periampullary pancreatic carcinoma in a patient with Gardner's syndrome. The primary tumor, the liver metastasis, and passages 6 and 15 of the cell line were characterized cytogenetically. The only aberration common to all samples was a der(15)t(8;15); this was probably the primary chromosomal abnormality. Loss of the short arm of chromosome 19 was also found in all samples but was brought about by different aberrations in the primary tumor and the metastasis. The secondary aberrations characteristic of clonal evolution often included further gain of 8q material but losses from 1p, 6q, and chromosomes 17 and 18, all of which have been seen before in sporadic pancreatic and colorectal carcinomas. This is the first cell line established from a tumor in a Gardner's syndrome patient and also the first characterization of an abnormal tumor karyotype associated with this autosomal dominant cancer syndrome.

Morphologic, immunologic, and cytogenetic features were studied in 30 newly diagnosed patients with CD34-positive (CD34+) de novo acute myeloid leukemia (AML) in comparison with 30 patients with CD34-negative (CD34-) AML. Karyotype at diagnosis was abnormal in 25/30 CD34+ AML patients, of which nine had major karyotype aberrations (MAKA). Clonal chromosome changes were detected in 9/30 patients with CD34- AML. The most frequent chromosome aberration in CD34+ patients was -5/5q-, an aberration showing a strong association with the M2 FAB subtype of AML. Other recurring chromosome changes involved chromosome 16q (four cases) and chromosome 17p (three cases). Total or partial monosomy 7q was detected in three cases. Among CD34- AML, two patients had the classical t(15;17) and two had structural aberrations of 6q. Among patients with CD34+ AML, nine had MAKA in association with trilineage myelodysplasia (TMDS). TMDS was infrequent in CD34+ AML without MAKA and in CD34- AML. Complete remission (CR) was achieved in 8/30 CD34+ AML (26%), as compared with 22/30 CD34- AML (73%), and median survival was 2 months in the former group and 8 months in the latter. No patient with CD34+ AML and MAKA achieved CR, whereas 8/21 CD34+ AML without complex chromosome changes or with normal karyotype achieved CR. In conclusion, a distinct cytogenetic profile may be associated with CD34+ AML. Cytogenetic findings in CD34+ AML may be clinically relevant in that they may disclose a subset of patients with MAKA with a low CR rate.

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.

The phenotypic progression of colorectal tumors is driven by their step-by-step acquisition of genomic alterations. These pathogenetically important mutations are at the same time markers of tumor clonality. The aim of this study was to describe the clonal relation among synchronous colorectal adenomas. Twenty-four colorectal adenomas from 11 patients were subjected to chromosome banding analysis. Clonal chromosome abnormalities were found in 20 tumors. Recurrent structural rearrangements involved chromosomes 1, 13, 17, and 18. The most common numerical changes were gain of chromosomes 7, 13, 20, and 3 and loss of chromosome 18. Eight adenomas had subclones as evidence of clonal evolution. Similar clones in separate polyps were seen in tumors from 6 patients; these adenomas were always located in the same part of the large bowel. In 2 patients, both with one rectal adenoma and one adenoma in the colon, no karyotypic similarity between the lesions was found. Our findings indicate that whereas close, but macroscopically distinct, synchronous colorectal adenomas usually have a common pathway of progression, perhaps even the same clonal origin, large bowel adenomas at a considerable distance from one another exhibit karyotypic differences, indicating that they arise independently.

An improved method for fluorescence in situ hybridization (FISH) investigation of old, previously G-banded, mounted chromosome preparations with chromosome specific painting probes and centromere-specific probes is described. Before hybridization, the slides are incubated in xylene until the coverslips detach spontaneously;any mechanical manipulation will jeopardize the results. The success of chromosome painting is improved by excluding the regular RNase treatment step prior to hybridization. Additional changes compared with standard FISH protocols are that the 2 X SSC step is omitted, that the amount of added probe is increased approximately 2.5 times, and that the amplification of signals is performed twice. The applicability of the method, which allows double painting with two differently labeled probes using two differently fluorescing colors, was tested on 11 cases involving different chromosome abnormalities and different types of material, including short-term cultures of epithelial and mesenchymal tumors, blood, leukemic bone marrow, and long-term cultures of a cell line derived from an epithelial tumor. Success was achieved even with chromosome preparations that were several years old.

Chromosome analysis of short-term cultured breast carcinoma cells revealed trisomy 12 in four cases. In one tumor it was the only abnormality. The second case showed cytogenetic polyclonality, but the mainline had +12 as the sole change. In the remaining two tumors, trisomy 12 was part of more complex karyotypes. These findings, especially when coupled with similar information on previously published cases, show that gain of chromosome 12 is a recurrent and sometimes early event in breast carcinogenesis.

To better define the role of interleukin-3 (IL-3) and IL-6 in the cytogenetic analysis of multiple myeloma (MM), we performed concomitant chromosome and cytologic studies in 34 patients. In each case, 10-30 x 10(6) bone marrow cells were incubated in two independent cultures consisting of conventional cytogenetic medium with and without IL-3 plus IL-6 added for 72 hours. 1-ml aliquots of each culture were aspirated at 24, 48, and 72 hours and exposed to colcemid for 6 hours. Cytospin preparations were then made and mitotic cells were counted and identified as plasma cells or as nonmalignant cells based on their reactivity with an appropriate anti kappa/lambda serum. Slides for conventional cytogenetic analysis were prepared at 72 hours. A greater than two-fold increase of mitotic plasma cells was observed in cytospin preparations from stimulated cultures versus unstimulated cultures in 15 of 34 cases, whereas a less than 2-fold increase, no variation or no mitosis was recorded in 19 cases. Comparison of the number of mitotic plasma cells in stimulated cultures at 24, 48, and 72 hours showed a decreased mitotic activity at 72 hours. Clonal abnormalities were detected by conventional cytogenetic analysis in 19 of 34 cases (55.8%). Recurrent clonal aberrations involved chromosome 13 (4 cases), chromosomes 1p, and 14q (3 cases); chromosomes 3p, 6q, 7q, and 9q (2 cases). We conclude that IL-3 + IL-6 may increase the number of dividing plasma cells in cytogenetic cultures and that a 2-day culture with these cytokines may facilitate the detection of chromosome abnormalities in MM.

Adenomyosis is a uterine disease whose defining characteristic is the presence deep in the myometrium of endometrial glands and stroma. The condition is believed to arise from inordinate downward growth by contiguity from the endometrium rather than from in situ metaplasia or neoplasia. No acquired chromosome abnormalities have been associated with adenomyosis before. We analyzed short-term cultures from three cases and detected in all of them a del(7) (q21.2q31.2), a karyotypic anomaly that has hitherto been found repeatedly only in uterine leiomyomas. The cytogenetic similarity to leiomyoma suggests that the del(7q) was present in the mesenchymal or, more precisely, smooth muscle cells of the adenomyosis lesions. The very fact that clonal chromosome abnormalities were present questions whether the prevailing understanding of adenomyosis pathogenesis is adequate; the cytogenetic data would better fit a model of the disease envisioning the intramyometrial endometrial foci as having arisen through a neoplastic process.

Cytogenetic investigation was attempted on 15 endometrial tumors. Whenever possible, a combination of direct harvesting and short-term culture (with or without prior methotrexate synchronization) was used. The analysis was successful in 13 cases: 12 carcinomas of stage I and one atypical hyperplasia. Clonal abnormalities were found in 10 tumors, whereas the remaining three showed a normal karyotype. The modal chromosome number was near-diploid. The abnormal karyotypes contained relatively simple numerical or structural aberrations in all but one tumor, a serous papillary carcinoma with multiple complex changes as well as cytogenetic evidence of intratumor heterogeneity. Gain of 1q, trisomy for chromosomes 2, 7, 10 (this trisomy was shown by in situ hybridization to be present also in a large number of interphase cells), and 12, and loss of chromosome 22 were recurrent aberrations; these are also the cytogenetic anomalies that have been consistently associated with endometrial carcinomas in previous studies. The utilization of both direct harvesting and short-term culture in several cases increased the frequency with which abnormal karyotypes were found; sometimes aberrations were found by the first method but not by the other, and vice versa. Never were different clonal anomalies found by the two approaches in the same case. Synchronization of the cultures generally led to chromosome preparations with more mitoses and of better quality. Again, no different anomalies were found in synchronized and standard cultures from the same tumor.

Cytogenetic analysis of short-term cultures of five phyllodes tumors of the breast-classified as benign (one tumor), borderline malignant (two tumors removed from the same breast in 1991 and 1993), and malignant (two tumors)--revealed clonal changes with simple structural abnormalities in the benign tumor, the borderline malignant tumors, and one malignant tumor in which benign areas and areas of borderline malignancy were also present. In contrast, the malignant tumor without admixed borderline malignant or benign areas had a complex karyotype. The karyotype of the benign phyllodes tumor was 46,XX,del(12)(p11p12)/46,XX,t(8;18)(p11;p11)/46,XX. The first borderline malignant phyllodes tumor had t(3;20)(p21;q13) as the sole abnormality. When the tumor recurred, this was no longer the only clone detected and the tumor karyotype was now 46,XX,t(3;20)(p21;q13)/46,XX,t(9;10)(p22;q22)/46,XX,t(1;8) (p34;q24)/46,XX,del(11)(q22-23)/46,XX. The malignant/borderline malignant/benign tumor had t(1;6)(p34;p22) as the sole clonal abnormality. Finally, the karyotype of the malignant phyllodes tumor which contained no benign or borderline malignant areas was 42,XX,der(1)t(1;4)(q21;q21),der(3)t(3;17)(q29;q21), -4,i(8)(q10), -10, -13,i(13)(q10),der(14)t(1;14)(q21;p11),der(14)t(4;14) (p12;p11), -17/80-90,idemx2, +del(1)(q12), +i(1)(p10), +dic(5;5)(p14;p14), +i(6)(p10), +del(7)(p11), +dup(7)(q11q36), +i(15)(q10),inc/46,XX. The findings indicate some cytogenetic similarities between benign/borderline malignant phyllodes tumors and fibroadenomas of the breast, presumably reflecting similar pathogenetic mechanisms in the two types of mixed-lineage tumors.

Short-term cultures from three carcinomas of the gallbladder were cytogenetically analyzed. All three had an abnormal karyotype. The modal chromosome number was near- or hypertriploid in two tumors and near diploid in the third. Structural rearrangements of chromosomes 1 and 3, loss of material from the long arm of chromosome 18, and loss of chromosome 21 material were common to all three tumors and would seem to be the best candidates for nonrandom karyotypic changes in carcinomas of the gallbladder.

A cell line was established from a liver metastasis of a periampullary pancreatic carcinoma in a patient with Gardner's syndrome. The primary tumor, the liver metastasis, and passages 6 and 15 of the cell line were characterized cytogenetically. The only aberration common to all samples was a der(15)t(8;15); this was probably the primary chromosomal abnormality. Loss of the short arm of chromosome 19 was also found in all samples but was brought about by different aberrations in the primary tumor and the metastasis. The secondary aberrations characteristic of clonal evolution often included further gain of 8q material but losses from 1p, 6q, and chromosomes 17 and 18, all of which have been seen before in sporadic pancreatic and colorectal carcinomas. This is the first cell line established from a tumor in a Gardner's syndrome patient and also the first characterization of an abnormal tumor karyotype associated with this autosomal dominant cancer syndrome.

Morphologic, immunologic, and cytogenetic features were studied in 30 newly diagnosed patients with CD34-positive (CD34+) de novo acute myeloid leukemia (AML) in comparison with 30 patients with CD34-negative (CD34-) AML. Karyotype at diagnosis was abnormal in 25/30 CD34+ AML patients, of which nine had major karyotype aberrations (MAKA). Clonal chromosome changes were detected in 9/30 patients with CD34- AML. The most frequent chromosome aberration in CD34+ patients was -5/5q-, an aberration showing a strong association with the M2 FAB subtype of AML. Other recurring chromosome changes involved chromosome 16q (four cases) and chromosome 17p (three cases). Total or partial monosomy 7q was detected in three cases. Among CD34- AML, two patients had the classical t(15;17) and two had structural aberrations of 6q. Among patients with CD34+ AML, nine had MAKA in association with trilineage myelodysplasia (TMDS). TMDS was infrequent in CD34+ AML without MAKA and in CD34- AML. Complete remission (CR) was achieved in 8/30 CD34+ AML (26%), as compared with 22/30 CD34- AML (73%), and median survival was 2 months in the former group and 8 months in the latter. No patient with CD34+ AML and MAKA achieved CR, whereas 8/21 CD34+ AML without complex chromosome changes or with normal karyotype achieved CR. In conclusion, a distinct cytogenetic profile may be associated with CD34+ AML. Cytogenetic findings in CD34+ AML may be clinically relevant in that they may disclose a subset of patients with MAKA with a low CR rate.

Cytogenetic analysis of short-term cultures of a nonneoplastic focal steatosis of the liver showed trisomy 7 as the sole chromosomal change. This finding, especially when viewed in light of previous reports describing +7 in nonneoplastic tissues, strongly suggests that trisomy 7 cannot be considered a tumor-specific abnormality when it occurs as the only change. The cell type in which +7 is present is not yet known.

Short-term cultures of four abdominal smooth muscle tumors, three leiomyosarcomas and one leiomyoma, were analyzed cytogenetically. A low-grade malignant, epithelioid leiomyosarcoma had a normal karyotype. The other two leiomyosarcomas had abnormal karyotypes; one was near-diploid, and the other was near-triploid. Structural rearrangements of the short arm of chromosome 16 and monosomies of chromosomes 14, 15, and 22 were observed in both tumors. When our cases and previously published abdominal leiomyosarcomas are viewed in conjunction, loss of chromosomes 14, 15, and 22 are the most frequent abnormalities. The leiomyoma, the second cytogenetically abnormal nonuterine leiomyoma reported to date, had a hyperdiploid karyotype with a chromosome number of 56 and structural rearrangements of chromosomes 9, 14, and 19. The only aberrations similar to those observed in the previously reported esophageal leiomyoma were trisomies of chromosomes 7 and 8.

Short-term cultures of three primary hepatocellular carcinomas were cytogenetically analyzed. Case 1 displayed a normal karyotype. Case 2 had, in addition to cells with a normal male chromosome complement, a clone with −Y. In case 3, two abnormal clones were found, one with −Y and one with a highly aberrant karyotype: 71–79,XX,−Y,(3n+/-),+3,−8,−16,−17,−21,dez(1)t(1;?) (p36;?),del(1)(p11),+dez(1)t(1;?)(q21;?),+del(1)(q32),+der(3)t(1;?;3)(3qter→3p11::?::1p12→1p36::?), der(6)t(6;8)(q12;q13),+der(6),9p+,+del(9)(q13),del(10)(q24),dez(12)t(12;?)(p13;?),inv dup(12)(q11q24), der(13)t(10;13)(q11;p13),+1–9mar. Our results, collated with the findings in one previously published primary hepatocellular carcinoma and in three cell lines, suggest that structural changes of chromosomes 1 and 6, leading to loss of 1p and 6q material, and loss of chromosome 16 are frequent events in hepatocellular carcinogenesis.

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.

Cytogenetic analysis of short-term cultures from 10 uterine leiomyomas revealed normal karyotypes in 8 and clonal complex chromosome rearrangements in 2 tumors. In both leiomyomas with clonal abnormalities, 12q14, but not 14q22–24, was involved in translocations with 1q43 in one tumor and with 12q24 in the other. Additional chromosome abnormalities were found in both cases: 1–5 rings and monosomy of chromosome 9 in case 1, and complex numerical and structural abnormalities of chromosomes 1, 6–8, 11, 13, 16, 17, and 22 in case 2. The consistent cytogenetic rearrangement of 12q14 in uterine leiomyomas, sometimes without concomitant 14q changes, indicates that a gene of critical importance for leiomyoma development may be found in this band.