Lack of referral for genetic counseling and testing in BRCA1/2 and Lynch syndromes: a nationwide study based on 240,134 consultations and 134,652 genetic tests

Breast Cancer Res Treat. 2013 Aug;141(1):135-44. doi: 10.1007/s10549-013-2669-9. Epub 2013 Aug 24.

Abstract

Based on nationwide data from the French national cancer institute (INCa), we analyzed the evolution of cancer genetics consultations and testing over time, and the uptake of targeted tests in relatives of families with BRCA1/2 or MMR genes mutation. Genetic testing and consultations for familial high-risk individuals are exclusively funded and monitored by the INCa in France. All nationwide cancer genetics centers reported annually standardized parameters of activity from 2003 to 2011. The analysis included a total of 240,134 consultations and 134,652 genetic tests enabling to identify 32,494 mutation carriers. Referral for hereditary breast and ovarian cancer (HBOC) or colorectal cancer predisposition syndromes represented 59 % (141,639) and 23.2 % (55,698) consultations, respectively. From 2003 to 2011, we found a dramatic and steady increase of tests performed for BRCA1/2 (from 2,095 to 7,393 tests/year, P < 0.0001) but not for MMR genes (from 1,144 to 1,635/year, P = NS). The overall percentage of deleterious mutations identified in the probands tested was 13.8 and 20.9 % in HBOC and Lynch syndromes, respectively. Pooled analysis for BRCA1/2 and Lynch syndrome tests showed an inverse relationship between the percentage of mutation detected and the absolute number of tests performed over the time (overall Cochran-Armitage test for trend: P < 0.001). In families with BRCA1/2 or MMR identified mutations, there was an average number of 2.94 and 3.28 relatives performing targeted tests, respectively. This nationwide study shows a lack of referral and genetic testing in Lynch as compared to HBOC syndromes. Only a third of relatives of a proband with a predisposing mutation performed a targeted test. Enhanced information about benefit of genetic testing should be given to clinicians and patients for Lynch syndrome and relatives of a proband carrying an identified predisposing mutation.

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics*
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / prevention & control
  • Cancer Care Facilities / statistics & numerical data
  • Colorectal Neoplasms, Hereditary Nonpolyposis / genetics*
  • Colorectal Neoplasms, Hereditary Nonpolyposis / prevention & control
  • DNA Mismatch Repair / genetics
  • DNA Mutational Analysis / statistics & numerical data
  • DNA-Binding Proteins / genetics*
  • Family Health
  • Female
  • France
  • Genes, BRCA1*
  • Genes, BRCA2*
  • Genetic Carrier Screening
  • Genetic Counseling / statistics & numerical data*
  • Genetic Counseling / trends
  • Genetic Testing / statistics & numerical data*
  • Genetic Testing / trends
  • Humans
  • Laboratories / statistics & numerical data
  • Male
  • MutL Protein Homolog 1
  • MutS Homolog 2 Protein / genetics*
  • Mutation
  • Neoplastic Syndromes, Hereditary / genetics*
  • Neoplastic Syndromes, Hereditary / prevention & control
  • Nuclear Proteins / genetics*
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / prevention & control
  • Referral and Consultation / statistics & numerical data*
  • Referral and Consultation / trends

Substances

  • Adaptor Proteins, Signal Transducing
  • DNA-Binding Proteins
  • G-T mismatch-binding protein
  • MLH1 protein, human
  • Nuclear Proteins
  • MSH2 protein, human
  • MutL Protein Homolog 1
  • MutS Homolog 2 Protein