DNA cytofluorometry in micro-dissected paraffin embedded breast tissue: description of a method.

DNA microfluorometry on smears obtained from paraffin embedded tissue has been shown to be a distinctive possibility. In this paper a simple method for the detachment of cells from mammary ducts and ductules is described. Areas of interest were selected in conventional slides stained with Haematoxylin and Eosin. The corresponding paraffin embedded block was then dewaxed. The areas under study were retraced with a stereomicroscope and the cells within ducts and ductules were scraped out with a 0.4 mm diameter fine needle. Cells were isolated with mechanical and enzymatic procedures and stained with the Feulgen reaction. The DNA content of single cells was then measured using a microfluorometer.