Clinical follow up of Mexican women with early onset of breast cancer and mutations in the BRCA1 and BRCA2 genes

Objective. This study describes the presence of mutations in BRCA1 and BRCA2 genes in a group of Mexican women and the clinical evolution of early onset breast cancer (EOBC). Material and Methods. A prospective hospital-based study was performed in a sample of 22 women with EOBC (7 in clinical stage IIA, 8 in IIB, and 7 in IIIA). The patients attended a tertiary care hospital in northeastern Mexico in 1997 and were followed up over a 5-year period. Molecular analysis included: 1) a mutation screening by heteroduplex analysis (HA) of BRCA1 and BRCA2 genes and 2) a sequence analysis. Results. Of 22 patients, 14 (63.6%) showed a variant band detected by heteroduplex analysis of the BRCA1 and BRCA2 genes: 8 polymorphisms, 4 mutations of uncertain significance, and 2 novel truncated protein mutations, one in BRCAI (exon II, 3587delT) and the other in the BRCA2 gene (exon II, 2664InsA). Conclusions. These findings support future studies to determine the significance and impact of the genetic factor in this Mexican women population.