BRCA1/BRCA2 gene mutation positive

Laboratory

• BRCA1/BRCA2 genotyping

Clinical significance

• BRCA1/BRCA2 gene mutation-related cancers include:
  • breast cancer
  • ovarian cancer
  • peritoneal cancer
  • fallopian tube cancer

Radiology

• women with BRCA gene mutation should begin breast cancer screening at age 25 with MRI & mammography beginning at age 30 years.

Complications

• risk of ovarian cancer 4% between age 35-40 years in women with deleterious BRCA1 mutation
• risk of ovarian cancer 1% between age 35-50 years in women with deleterious BRCA2 mutation

Management

• prophylactic bilateral mastectomy (by age 35 ?)* reduces risk of breast cancer 90% in women with BRCA gene mutation
• prophylactic bilateral salpingo-oophrectomy (BSO) by age 35 reduces risk of ovarian cancer 80% in women with BRCA1 gene mutation
  • does not reduce risk of breast cancer
• prophylactic BSO by age 45 for BRCA2 mutation

* age = 35 suggested by analogy to prevention of ovarian cancer

More general terms

• BRCA gene mutation (BRACAnalysis CDx)
• abnormal laboratory test
• susceptibility to breast cancer

More specific terms

• BRCA1 gene mutation positive
• BRCA2 gene mutation positive

Additional terms

• BRCA1/BRCA2 genotyping
• breast cancer type 1 susceptibility protein (BRCA1)
• breast cancer type 2 susceptibility protein (Fanconi anemia group D1 protein, BRCA2, FACD, FANCD1)