CYTOGENETIC STUDIES OF BREAST CARCINOMAS - DIFFERENT KARYOTYPIC PROFILES DETECTED BY DIRECT HARVESTING AND SHORT-TERM CULTURE

Chromosome analysis was performed on samples from 85 consecutive patie nts with breast cancer by one or more of three different methods: dire ct harvest, culture after mechanical disaggregation, and culture after collagenase digestion. Metaphases suitable for karyotyping were obtai ned in 70% of the cases; direct harvest yielded metaphases in 29% and cultures without and with digestion in 40% and 59%, respectively. Chro mosomal abnormalities were detected in 37 cases. Cells judged to be ph enotypically abnormal in culture were twice as likely to reveal chromo somal aberrations as normal-looking cells. Eight cases showed multiclo nal abnormalities. Significant differences were detected in the karyot ypic profile depending on the method used. With direct harvest, the yi eld of complex chromosomal changes was 87%, compared to 44% after cult ure of digested tissue (P < 0.01), and also polyploidy was more common in direct-harvested samples. Detailed karyotypic analysis was possibl e in 29 primary tumors. The chromosomes most frequently involved were 1, 3, 7, 11, 16, and 17. Recurrent structural abnormalities were der(1 ;16)(q10;p10), i(1)(q10), del(6)(q21), and del(1)(p22). Breakpoints cl ustered to the centromere regions of chromosomes 1, 3, 11, 15, and 16 and to the short arms of chromosomes 7, 17, and 19. Seven of twenty-ni ne fully analyzed cases had a family history of breast cancer, and cha nges of chromosomes 1, 3, and 15 seemed to be more common in these cas es. There was an association between karyotype and survival: The 3 yea r survival was 63% in patients with complex karyotypic changes and 92% in those without complex changes. (C) 1995 Wiley-Liss, Inc.