RAD51D mutations have been recently identified in breast (BC) and ovarian cancer (OC) families. Although an etiological role in OC appears to be present, the association of RAD51D mutations and BC risk is more unclear. We aimed to determine the prevalence of germline RAD51D mutations in Spanish BC/OC families negative for BRCA1/BRCA2 mutations. We analyzed 842 index patients: 491 from BC/OC families, 171 BC families, 51 OC families and 129 patients without family history but with early-onset BC or OC or metachronous BC and OC. Mutation detection was performed with high-resolution melting, denaturing high-performance liquid chromatography or Sanger sequencing. Three mutations were found in four families with BC and OC cases (0.82%). Two were novel: c.1A>T (p.Met1?) and c.667+2-667+23del, leading to the exon 7 skipping and one previously described: c.674C>T (p.Arg232*). All were present in BC/OC families with only one OC. The c.667+2-667+23del cosegregated in the family with one early-onset BC and two bilateral BC cases. We also identified the c.629C>T (p.Ala210Val) variant, which was predicted in silico to be potentially pathogenic. About 1% of the BC and OC Spanish families negative for BRCA1/BRCA2 are carriers of RAD51D mutations. The presence of several BC mutation carriers, albeit in the context of familial OC, suggests an increased risk for BC, which should be taken into account in the follow-up and early detection measures. RAD51D testing should be considered in clinical setting for families with BC and OC, irrespective of the number of OC cases in the family. What's new? RAD51D mutations have recently been identified in breast (BC) and ovarian (OC) cancer families. Although RAD51D mutations are associated with hereditary OC, such an association is less clear in BC. This study determined the prevalence of germline RAD51D mutations in Spanish BC/OC families testing negative for BRCA1/BRCA2 mutations. RAD51D mutations were found in almost 1% (4/491) of BC/OC families. These families had only one OC case, with some carriers presenting BC, suggesting that RAD51D testing should be offered to all BC/OC families. The existence of an increased risk of BC should be considered when setting the follow-up and prevention measures. © 2013 UICC.
|Revista||International Journal of Cancer|
|Estat de la publicació||Publicada - 1 de maig 2014|