Chromosome abnormalities in breast fibroadenomas.

Cytogenetic analysis of 25 breast fibroadenomas (FA) showed clonal chromosome alterations in three cases. Insertion (12;?) (q15;?) and deletion (2) (q14q31 or q32) were detected as a sole change in cases 1 and 3, respectively. Case 2 displayed the karyotype 45,XX,t(1;8;16)(q25;q23;q22-23), add (7)(p14), rea(15), -17. The present findings are discussed together with the reports on FA in the literature.

Cytogenetic and pathologic aspects of Ewing's sarcoma and neuroectodermal tumors.

Diagnostic classification of poorly differentiated, round cell, primitive neuroectodermal neoplasms, including Ewing's sarcoma, peripheral neuroepithelioma, Askin's tumor, and esthesioneuroblastoma, is challenging to the surgical pathologist using conventional histopathologic approaches because of very similar and overlapping morphologic and cytologic features. Furthermore, distinguishing these neoplasms from neuroblastoma, embryonal rhabdomyosarcoma, small cell osteogenic sarcoma, and non-Hodgkin's lymphoma can be difficult. This paper describes and reviews the cytogenetic and molecular genetic changes in these tumors and demonstrates how the ability to detect these changes has enabled a greater understanding of the histogenesis, classification, diagnosis, and prognosis of these neoplasms.

Cytogenetic and fluorescence in situ hybridization analysis of breast fibroadenomas.

We report cytogenetic and fluorescence in situ hybridization (FISH) analysis findings in 7 patients with breast fibroadenomas (FA). Three patients were cytogenetically abnormal. One patient had a translocation t(3;5)(p22;q13), the second had trisomy 8, and the third two clones, 47, XX, +11 and 47,XX, +10.

Analysis of a giant marker chromosome in a well-differentiated liposarcoma using cytogenetics and fluorescence in situ hybridization.

Well-differentiated liposarcomas (LPS) are cytogenetically very complex, characterized by giant marker chromosomes, ring chromosomes, and telomeric associations. We report a case of well-differentiated LPS in which the only cytogenetic anomaly was an additional giant marker. In an attempt to identify the origin of this marker, centromeric probes (chosen on the basis of the morphology of the marker) to chromosomes 1,2,3,4,6,7,8,9,10,11,12,16,17, and X and a shared satellite probe for chromosomes 1,5, and 19, were used with fluorescence in situ hybridization (FISH). This was successful at eliminating certain chromosomes as candidates for centromeric trisomy but could not identify the origin of the marker. This case is unusual in that it does not conform to the typical cytogenetic pattern for well-differentiated LPS and is the first known example with an apparently normal diploid karyotype with only one additional change.

del(6q) as a possible primary change in malignant mesothelioma.

Detailed cytogenetic and fluorescence in situ hybridization analysis of an untreated pleural malignant mesothelioma revealed two clonal cell populations, both with a single abnormality affecting chromosome 6. The majority of cells had a deletion together with an inversion of the long arm of chromosome 6, while a smaller population showed loss of this chromosome. The normal 6 was retained. Most reports show that mesotheliomas are characterized by complex karyotypes, involving numerous chromosomes. Abnormalities of chromosome 6 (particularly deletions of the long arm) are among the consistent changes. Our case apparently is the first report of a mesothelioma with a single change involving chromosome 6, which could be the primary cytogenetic change.

Ring chromosome in a dermatofibrosarcoma protuberans.

We report the cytogenetic findings in a case of dermatofibrosarcoma protuberans in a 40-year-old male. Chromosome analysis revealed one clone consisting of +7, +11, +13, +14, +15, and a ring chromosome. This is consistent with two previously reported cases, each of which also had a single ring chromosome.

The proliferative activity of B-chronic lymphocytic leukaemia lymphocytes prior to and after stimulation with TPA and PHA.

The proliferative activity of B-CLL lymphocytes from 10 patients was investigated both prior to and after stimulation with TPA and PHA. The analysis of cell cycle-associated features such as BrdU incorporation and the expression of the nuclear proliferation-associated antigen, Ki-67, together with the phenotypic profile of the cells, was performed using double colour immunofluorescent methods. The unstimulated B-CLL cells represented a homogeneous population with the same cell cycle position (G0) as resting peripheral blood lymphocytes. After TPA stimulation 22.7% of the lymphocytes were found in G1, 9.4% in S + G2/M and 13.4% in post-M. PHA stimulation induced a greater proportion of cells in G1, i.e. 35% and 17.8% into S + G2/M and 13.4% into post-M. Double colour immunofluorescence was able to demonstrate that in TPA cultures the majority of the stimulated lymphocytes originated from the malignant clone. Evidence of B-CLL lymphocyte proliferation using double colour labelling with BrdU and Ig kappa and/or Ig lambda showed that a small minority of B-CLL lymphocytes were stimulated into S + G2/M phases of the cell cycle. PHA was also capable of inducing a small proportion of B-CLL cells into mitosis although this proportion of cells was smaller compared to the TPA-stimulated lymphocytes.

An Analysis of Circulating CD4 Lymphocyte Subpopulations in B-Cell Chronic Lymphocytic Leukaemia.

The distribution of circulating CD4 lymphocyte subpopulations determined by reactivity with monoclonal antibodies anti-2H4 (CD45RA), anti-UCHL1 (CD45RO), anti-4B4 (CD29) and anti-Leu8, and analysed by dual colour immunofluorescence flow cytometry is described in a series of patients with B-CLL and in age-matched control subjects. The percentages and absolute numbers of CD4 cells reactive with anti-CD45RA, anti-CD45RO and anti-CD29 reagents were similar in the patient and control groups. In contrast, CD4+ Leu8+ cells (percentages and absolute numbers) were significantly reduced in B-CLL patients resulting in an inversion of the normal CD4+ Leu8+ :CD4+Leu8- ratio. The patients' clinical or therapeutic status did not appear to influence the levels of the respective CD4 subpopulations; nor was evidence of hypogammaglobulinaemia associated with specific numerical alterations in any of the CD4 subpopulations studied. It is proposed that, in B-CLL, the alterations in the CD4Leu8 subpopulations are associated with the disease process, whereas the distributions of CD4+CD45RA+, CD4+ CD45RO+ and CD4+ CD29+ cells reflect the normal physiological levels of these subpopulations in elderly subjects.