Prophylactic Surgery in the BRCA+ Patient: Do Women Develop Breast Cancer While Waiting?

Area of Science:

• Oncology
• Genetics
• Surgical Outcomes

Background:

• BRCA mutation carriers have a significantly elevated risk of developing breast cancer.
• Risk-reducing strategies include surveillance and prophylactic mastectomy with or without reconstruction.
• Patients undergoing prophylactic mastectomy aim to decrease their future cancer risk.

Purpose of the Study:

• To determine the incidence of breast cancer diagnosed before prophylactic surgery in BRCA mutation carriers.
• To identify modifiable factors within the patient's journey contributing to pre-surgical cancer development.
• To analyze the time intervals between mutation disclosure, surgical decision-making, and the procedure itself.

Main Methods:

• Historical cohort study of 333 BRCA mutation carriers from the British Columbia Cancer Hereditary Cancer Program (2000-2012).
• Patients were categorized into surveillance (S) and prophylactic mastectomy with immediate breast reconstruction (PM/IBR) groups.
• Analysis of cancer incidence, time to PM/IBR, and patient journey timelines.

Main Results:

• The median time from mutation disclosure to surgery was 31 months.
• 6% of patients undergoing prophylactic mastectomy developed breast cancer prior to surgery (interval cancer).
• Patients on surveillance had a higher incidence of breast cancer (14%) during the study period.

Conclusions:

• A significant proportion of BRCA carriers develop breast cancer before prophylactic surgery, particularly during the decision-making phase.
• Strategies to expedite surgical decision-making and improve access to surgery are crucial for this high-risk population.
• Prioritizing waitlists and allocating dedicated operating time can reduce interval cancer rates in BRCA mutation carriers.