DETECTION OF CHROMOSOMAL NUMERICAL ABNORMALITIES IN CLINICAL BREAST-TUMOR FINE-NEEDLE ASPIRATIONS BY FLUORESCENCE IN-SITU HYBRIDIZATION (FISH) - REFINEMENT OF A METHOD

This study sought to refine a fluorescence in situ hybridisation (FISH ) technique for the study of numerical chromosome aberrations in cells recovered from breast rumours by fine-needle aspiration (FNA). Such t echniques have been used to study numerical aberrations of chromosomes from tumours from many sites. This technique is intended for use in a routine cytopathology laboratory, and no specialised cytogenetics kno wledge is necessary. Slide preparation, slide and probe denaturation, and stringency conditions were investigated. We found that the simples t slide preparation technique (direct smears) gave the best results. N o difference was seen when slide and probe were denatured together or separately. Stringency conditions must be adapted to suit particular p robes. Study of numerical chromosomal changes map help determine their significance in the clinical progression of the disease. Such changes may prove to have prognostic significance and therefore influence tre atment of breast cancer. FISH on interphase cells is a technically str aightforward reproducible technique, suited to the study of numerical chromosome aberrations in tumour cells. The method has the potential f or use in the studs of malignant cells from sites other than breast, i ncluding ovary, prostate, lung and bladder.