Cytogenetics of epithelial hyperplasias of the human breast

Generally, benign breast lesions behave like innocuous and limited prolifer ations; however, sometimes they can represent precancerous pathologies. The cytogenetic analysis of five mammary epithelial hyperplasias is reported. Four cases had clonal chromosome alterations. All of the cases presented a modal number of 46 chromosomes. Chromosome 9 monosomies and chromosome 1 de letions were common in these benign tumors. The study of benign proliferati ons of the breast may reveal a possible relationship between chromosomal al terations and the conditions of the tissue. (C) 2000 Elsevier Science Inc. All rights reserved.