Locoregional Management of Hereditary Breast Cancer

Abstracts

Hereditary breast cancer represents only 5–10% of diagnosed cases with germline mutations in BRCA1 and BRCA2 accounting for the majority of situations with an identifiable pathogenic mutation. Cumulative breast cancer risk estimates to age 70 range from 30 to 85% in BRCA mutation carriers. Differences in sample populations, testing methodology and environmental factors are possible explanations for reported variations in risk estimation.

Genetic testing is becoming more frequent and can influence treatment decision making. Testing for BRCA1 and BRCA2 has been available for the last 20 years, but new sequencing technologies and easier patent laws have made multipanel testing widely available at lower costs and in a more proficient way. However, clinical needs for genetic testing may not be adequately recognized due to lack of training in identifying high-risk patients. Although several guidelines are available to guide physicians in the detection of patients with a high probability of harbouring a mutation, it is important to have simple and reproducible methodologies to lessen the possibility of missing BRCA mutation carriers in the first approach of a newly diagnosed breast cancer patient.

In breast cancer diagnosed at young age, in triple negative breast cancer, in bilateral breast cancer and with a strong family history of breast and ovarian cancer, BRCA1 and BRCA2 are the most commonly assessed mutations.

A timely identification of carriers at diagnosis allows an informed discussion of locoregional and also systemic treatment options.

The optimal locoregional management reserved for patients with BRCA1 and BRCA2 mutations is still debated. The risk of ipsilateral breast recurrence, the impact of radiotherapy, the risk of contralateral breast cancer, the potential survival benefit of preventive surgery and individual risk factors that can have an impact in treatment choices should be discussed thoroughly with patients, before a final decision is taken.

Clinical guidelines for locoregional management of breast cancer in BRCA mutation carriers are still missing. Discussion in a multidisciplinary team is mandatory, and a case by case approach will lead to a more balanced choice using the published available evidence and always, taking into account, patients preferences.