Chromosome abnormalities in benign hyperproliferative disorders of epithelial and stromal breast tissue

Publisher Website
Google Scholar
Abstract
Cytogenetic analysis of short‐term cultures from 15 cases of benign proliferative breast disease (PBD), 10 diffuse PBD and 5 papillomas, and 15 fibroadenomas of the breast revealed clonal chromosome abnormalities in 7 diffuse PBD lesions, 4 papillomas and 5 fibroadenomas. The remaining 14 cases had a normal female chromosome complement. Cytogenetically unrelated abnormal clones were seen in 4 fibroadenomas and 2 PBDs. A single abnormal clone was found in 9 PBDs and I fibroadenoma. Three clonal abnormalities were seen as recurrent changes in 6 cases, namely interstitial deletions of 3p with 3p 12–14 as the minimally common deleted segment (in I papilloma, I diffuse PBD with atypia and I mixed‐pattern lesion with both papilloma and atypical diffuse PBD features), r(9)(p24q34) (in I diffuse PBD and I fibroadenoma), and del(l)(q12) (again in I diffuse PBD and I fibroadenoma). Intriguingly, 6 of the 16 abnormal cases had chromosome changes that have been seen repeatedly as primary abnormalities in breast carcinomas: der(16)t(l;16)(q10;p10), del(3)(p12p14), and del(l)(q12). We conclude that some of the chromosome anomalies frequently found in breast carcinomas are also present in PBD and fibroadenomas. These aberrations may be accepted as early, neoplasia‐relevant mutations. However, they do not seem to be sufficient by themselves to unleash a malignant process.