A comparative analysis of chromosomes and diagnostic cytology in effusions from 58 cancer patients

Cytogenetic Study of Pleural Effusions

Chromosome analysis of effusions has been recently regarded as useful means in the diagnosis of cancer. Cytological and cytogenetic findings of 19 pleural effusions from patients with benign and malignant diseases are compared. Conventional cytology does not always give correct positive results because of the high percentage of false negatives, whereas cytogenetic analysis reveals a considerable spread of the chromosome number in neoplastic fluid, with structural chromosome changes, marker chromosomes and minute fragments. Absence of mitosis does not exclude the malignant etiology of the effusion when the patient had been previously treated with antineoplastic drugs. Benign diseases were never falsely classified as malignant by cytogenetic analysis.

Cell-to-cell fusion as a link between viruses and cancer

The ability to fuse cells is shared by many viruses, including common human pathogens and several endogenous viruses. Here we will discuss how cell fusion can link viruses to cancer, what types of cancers it can affect, how the existence of this link can be tested and how the hypotheses that we propose might affect the search for human oncogenic viruses. In particular, we will focus on the ability of cell fusion that is caused by viruses to induce chromosomal instability, a common affliction of cancer cells that has been thought to underlie the malignant properties of cancerous tumours.

Isochromosome i(3q) and premature chromosome condensation are recurrent findings in chronic B-cell lymphocytosis with binucleated lymphocytes

Chronic B lymphocytosis with binucleated lymphocytes (LWBL) is a recently described entity. The lymphocytosis is stable over years and atypical binucleated lymphocytes are detected on peripheral blood smears. Further investigation has shown a predominance in females, a polyclonal increase in serum IgM and HLA-DR7 expression in most cases. In almost all cases cytogenetic studies with classical culture conditions have not shown any abnormality. We describe 7 patients with LWBL associated with an abnormal karyotype. An additional i(3q) was found in 6 cases. Premature chromosome condensation (PCC) was detected in all 7 cases. As both abnormalities are rarely present in other benign or malignant proliferations, we suggest a strong correlation between LWBL and i(3q) and/or PCC.

Premature chromosome condensation in children with acute lymphocytic leukemia (L1) and malignant histiocytosis

In this study we report the observation of premature chromosome condensation (PCC) in two children with acute lymphocytic leukemia L1 and one child with malignant histiocytosis. Cytogenetic analysis was performed on peripheral blood or bone marrow cells cultivated for 24 hours without mitogen. In all three reported cases the modal karyotype was normal, while 12.9%, 5.5%, and 5% of spreads with PCC was observed, respectively.

Flow cytometry and Feulgen cytophotometry in evaluation of effusions

Fifty-eight effusions (42 pleural and 16 ascitic fluids) from patients with and without cancer were analyzed by conventional cytology and the results compared with DNA patterns generated by flow cytometry of 10(4) nuclei and several modes of Feulgen cytophotometry. In 31 patients (24 without evidence of cancer and seven with history of cancer and cytologically negative fluids), the fluids were diploid by flow cytometry. One fluid with atypical cells from a lymphoma suspect was also diploid. Flow cytometry of 26 cytologically cancerous fluids disclosed aneuploid DNA patterns in 16 and diploid patterns in ten. Feulgen cytophotometry of 11 of these fluids (three aneuploid, eight diploid) was performed on nuclear preparations identical to those used in flow cytometry and on restrained smears used for visual analysis. The analysis was performed in two modes: as a study of 500 sequential nuclei in an automated system, mimicking flow cytometry, and visually selected large, presumably malignant nuclei. In nine of the 11 cases, the DNA content of visually selected cancer cells was aneuploid, even though this DNA pattern was not evident in the analysis of 500 sequential cells. In two cases, both diploid by flow cytometry, the Feulgen analysis confirmed the presence of cancer cells in the diploid range. In samples of 10(4) nuclei representing a mixed population of cells occurring in effusions, the presence of aneuploid cancer cells may not be disclosed by conventional flow cytometry. A larger sample of cells, a detailed analysis of DNA histograms, and perhaps sorting of select cells in the hypertetraploid range, may prove essential before flow cytometry can be accepted as a diagnostic tool in the laboratory in the assessment of effusions.

Premature chromosome condensation in human cervical carcinoma

Premature chromosome condensation was observed in 22 of 150 cases (15%) of cervical cancers studied with G-banding. The percentage of premature chromosome condensation in the tumors ranged from 1.5% to 8.9%. Premature chromosome condensation was present in greater frequency (16 of 22 cases) in tumors showing hyperdiploidy, suggesting that this could be a major mechanism of induction of polyploidy in addition to other operative mechanisms, such as endomitosis and endoreduplication. No relationship, either with the disease stage or prognosis, was evident.

Premature chromosome condensation: evidence for in vivo cell fusion in human malignant tumours

Premature chromosome condensation (PCC) was studied in direct preparations of tissues from patients with haematological diseases and carcinomas of various histological types. PCC was found in 6 out of 166 malignancies (128 haematological cases, 35 carcinomas and 3 malignant effusions) analysed with the GTG-technique. Chromosome analysis revealed S-phase and G1-phase PCC in each case; the frequency of PCC varied between 1, 4 and 8.6% of the metaphases analysed. It is suggested that PCC chromosomes, which represent cell fusion in vivo, are not very rare in naturally-occurring human malignancies, and that cell fusion may affect the malignant phenotype. In conjunction with other factors they may also explain the heterogeneity of tumour cell populations.

Use of Cytogenetic Analysis of Body Fluids in Cancer Diagnosis

Direct chromosome preparations were made from 52 malignant and 21 non-malignant effusions. An effusion was classified as malignant if 2% of the counted cells showed abnormal karyotypes. There was a significant relationship between diversified karyotypes and the pathological nature of tumours: diversity of karyotypes was much higher in undifferentiated adenocarcinoma, anaplastic carcinoma and embryonal cell carcinoma cells than in well-differentiated cancer cells. Diagnosis was positive for 38 of the 52 malignant effusions by cytological examination (73% sensitivity), and positive for 41 of the 52 by cytogenetic analysis (78% sensitivity). There were no false positive results using both cytogenetic and cytologic examinations (92% sensitivity). Particularly in patients with equivocal cytology, cytogenetic analysis appears to be a useful tool in the diagnosis of malignant effusions.

Premature chromosome condensation in human large bowel cancer

Two patients with large bowel cancer are described in whose tumors the presence of cells with premature chromosome condensation (PCC) was encountered. The percentage of PCC In the tumors was 6.9 and 6.6%. We hypothesize that the near tetraploid chromosome number present in the tumor cells in both patients may be the product of fusion of two near diploid malignant cells. Also it is speculated that some colorectal tumors with chromosomes ranging from the hypotriploid to the hypotetraploid levels may be the result of cell fusion.

C-group chromosome abnormalities in bone marrow cells of three children with dyshematopoiesis of unknown origin

Clinical and cytogenetic findings in three children with dyshaematopoiesis and bone marrow aneuploidy are described. Monosomy 7 was found in immature cells of one 10-year-old boy with myelofibrosis following a 3 years evolution of severe thrombocytopenia and anaemia. Trisomy 8 was found in 80% of the bone marrow metaphases of a 5 1/2-year-old girl with aplastic anaemia and Australia antigen positivity. During a 3 year observation period the number of cells with trisomy 8 regressed and eventually disappeared. Improvement of her clinical condition is present but still limited. Trisomy 8 was also found in all bone marrow cells of an 8-year-old girl with an undefined myeloproliferative disorder. Her disease was apparently related to collagen-vascular disorders like periarteritis or other necrotizing angiitis and presented with periods of exacerbation and periods of chronic evolution. Periods of exacerbation were accompanied by excessive myeloid proliferation. Repeated bone marrow cytogenetic analysis during the acute and chronic phases showed trisomy 8 in all the metaphases analysed. During the last episode of acute illness, further clonal evolution was observed, characterized by a translocation (8;17).

Cytological and cytogenetical analysis of thoracic duct lymph in patients with pulmonary carcinomas

Seven patients with squamous cell carcinomas of the lung and nodular metastases underwent Daniels' biopsy and cannulation of the thoracic duct. Lymph specimens obtained by aspiration the day after catheter insertion were examined by cytologic and cytogenetical techniques, including chromosome banding methods. In five of the seven cases maligant cells could be detected by karyotype analysis, whereas standard cytologic examinations yielded no positive diagnoses. This indicates that chromosome analysis is applicable as a diagnostic tool in lymph fluid.

Non-random chromosome changes in human cancer

Chromosome changes in human cancer cells appear to evolve by non-random losses and/or gains of particular homologues or groups. It is probable that some of the apparent losses or gains actually represent formation of new chromosome structures, which are then classified as markers or are misclassified as normal homologues. In many cancers these changes appear to continue at a high rate throughout the life of the cancer (so that in some cancers almost every cell will exhibit a different karyotype). In other cancers the rate of change may be slow or arrested so that all cells will have the same abnormal karyotype. One very common step in karyotype evolution is doubling of the entire chromosome complement (2n → 4n or more commonly, S → 2S where S is the stemline number). The 2S cells tend to replace the original stemline. Homologues which have larger amounts of concentrated blocks of heterochromatin (i.e. late replicating DNA) seem more apt to be lost.