A SUBGROUP OF BREAST CARCINOMAS IS CYTOGENETICALLY CHARACTERIZED BY TRISOMY-12

Chromosome analysis of short-term cultured breast carcinoma cells reve aled trisomy 22 in four cases. In one tumor it was the only abnormalit y. The second case showed cytogenetic polyclonality, but the mainline had +12 as the sole change. In the remaining two tumors, trisomy 12 wa s part of more complex karyotypes. These findings, especially when cou pled with similar information on previously published cases, show that gain of chromosome it is a recurrent and sometimes early event in bre ast carcinogenesis. (C) Elsevier Science Inc., 1997.