Detection of numerical chromosomal abnormalities in malignant cells in fine needle aspirates by fluorescence in situ hybridization of interphase cell nuclei with chromosome-specific probes.

The feasibility of detecting numerical chromosomal abnormalities (NCA) in malignant cells on fine needle aspirates (FNA) using the fluorescent in situ hybridization (FISH) technique was tested on clinical specimens from patients with various neoplasms. Directly labeled DNA probes specific for chromosomes 8 and 12 were used for in situ hybridization to interphase cell nuclei. Thirty-nine of 42 samples from various sites were evaluable. Based initially on the Papanicolaou-stained slides, there were 32 malignant and 7 benign samples. Blind analysis (200 cells per sample) showed that all benign samples had a normal number of chromosomes, while 27 of 32 malignant samples showed different NCA composed of 5-95% of the cell population and ranging from 1 to 10 chromosome signals per cell. We conclude that interphase cytogenetic cell analysis of FNA by FISH is (1) feasible and gives superior signals for detection of NCA, and (2) relatively simple, with a turnaround time of less than 24 hours. This method may have diagnostic and prognostic application in the study of the biologic behavior of malignant neoplasms.