Detection of chromosomal aneusomy by fluorescence in situ hybridization infine-needle aspirates from breast tumors: Application to the preoperative diagnosis of breast carcinoma

BACKGROUND, The authors studied the clinical usefulness of fluorescence in situ hybridization (FISH) analysis of a numerical aberration of chromosomes (aneusomy) using fine-needle aspiration (FNA) samples from patients with b reast tumors in the preoperative diagnosis of breast carcinoma. METHODS. FNA samples were obtained from 176 breast tumors and were subjecte d to conventional cytology and FISH analysis using the centromere probes fo r chromosomes 1, 11, and 17. Patients with FNA samples that showed aneusomy in at least one of the three chromosomes were diagnosed as positive. RESULTS. Histologic examination revealed 157 malignancies and 19 benign res ults (10 fibroadenomas, 6 intraductal papillomas, 1 intracystic papilloma, and 2 ADH). The sensitivity, specificity, and diagnostic accuracy were 85.4 %, 94.7%, and 86.4%, respectively, for cytology and 90.4%, 100%, and 91.5%, respectively, for FISH. Of 15 breast malignancies that were diagnosed with indeterminate cytology, 13 were diagnosed as positive with FISH analysis ( sensitivity, 86.7%). CONCLUSIONS. The results demonstrate that the use of FISH in the diagnosis of FNA samples has a diagnostic accuracy comparable to conventional cytolog y and is useful in making a definitive diagnosis of malignancy (100% specif icity) in patients with indeterminate cytologic results, suggesting that FI SH diagnosis can be a good adjunct to conventional cytology. Cancer (Cancer Cytopathol) 2000;90:373-378. (C) 2000 American Cancer Society.