PLOIDY ANALYSIS BY IN-SITU HYBRIDIZATION OF INTERPHASE CELL-NUCLEI INFINE-NEEDLE ASPIRATES FROM BREAST CARCINOMAS - CORRELATION WITH CYTOLOGIC GRADING

Fine-needle aspirates from 54 breast cancer patients were investigated for numeric aberrations in chromosomes 6,7, 12, and 17 by in situ hyb ridization (ISH) of interphase cell nuclei. Ploidy findings were compa red with cytologic grading of tumors. Aneuploidy was found in 73% of c ases. Chromosomes 6 and 7 showed numeric abnormalities in 63% and 62% of cases, respectively, whereas chromosome 17 retained a disome patter n in 2/3 of the tumors. Thirteen cancers (28% of 47 with four analyzed probes) had a normal signal number in all four chromosomes. In 17 (36 %), all four had signal gain. Another 17 showed a mixed disome/aneusom e pattern. They presented a continuum of increasing numeric abnormalit ies, 82% disomy for chromosome 17, and 13 of them were grade 2, indica ting intermediate biologic properties. Correlation between grading and ploidy was good, with 10 of 11 grade 1 carcinomas showing diploidy, w hereas 33 of 36 grade 2 and 3 tumors had numeric aberrations. (C) 1997 Wiley-Liss, Inc.