Chromosome changes of in situ carcinomas in the female breast.

Eight lesions of ductal carcinoma in situ (DCIS) and one case of benign radial scar were investigated cytogenetically and compared with invasive ductal carcinomas. DCIS was shown to be associated with chromosome changes different from those of invasive carcinomas as concern ploidy levels. All cases exclusively contained abnormal metaphases, also the specimen that was classified as a benign radial scar. No consistent chromosome changes were found. Chromosome no. 1 was most frequently involved in marker chromosome formation.