ABSENCE OF TRISOMY-7 IN NONNEOPLASTIC HUMAN ASCITIC AND PLEURAL FLUIDCELLS - AN INTERPHASE CYTOGENETIC STUDY

Trisomy 7 is a frequent aneuploid change in lymphomas, adenocarcinomas , and malignant mesenchymal and neurogenic tumors. Moreover, it has be en observed in cultured and uncultured non-neoplastic cells from brain , kidney, liver, lung, and atherosclerotic plaques, among other tissue s, opening debate on the role of this change in normal and neoplastic tissue. We used nonradioactive in situ hybridization (ISH) with a biot inylated chromosome 7-specific alpha-satellite DNA probe to seek an ex tra copy of chromosome 7 in ascitic and pleural fluid interphase cells from 26 donors. The donors comprised 24 patients with nonmalignant cl inical history one patient with non-Hodgkin's malignant lymphoma (posi tive control), and one patient with chronic myeloid leukemia (CML, neg ative control). The highest frequency of fluid cells with three hybrid ization signals in patients without neoplasia was 0.5%, in contrast to the frequency of 40.5 % noted in the fluid cells of the patient with non-Hodgkin's malignant lymphoma. The results demonstrate that the fre quency of trisomic cells in pleural as well as in ascitic fluid is ver y low making possible use of the cells in ascitic or pleural fluids in identification of malignancy.