What are the guidelines for breast cancer screening in British Columbia (BC)?

Breast Cancer Screening Guidelines in British Columbia

The current guidelines for breast cancer screening in British Columbia recommend annual mammography screening starting at age 40, with a transition to biennial screening at age 55 for average-risk women, and continuing as long as they have good health with a life expectancy of at least 10 years. 1

Screening Recommendations by Age Group

Average-Risk Women

• Ages 40-44: Annual mammography (optional but recommended)
• Ages 45-54: Annual mammography
• Ages 55+: Biennial (every 2 years) mammography as long as in good health with life expectancy ≥10 years

High-Risk Women

• Women with known BRCA mutations or ≥20-25% lifetime risk:

  • Annual mammography AND annual MRI
  • Earlier screening initiation (typically by age 25-30)

• Women with family history of breast cancer:

  • Begin screening 10 years before the youngest age of diagnosis in the family
  • Generally not before age 30
  • Digital breast tomosynthesis (DBT) is preferred over standard digital mammography 1

Special Considerations

Dense Breasts

• Women with dense breasts should consider supplemental screening:
  • MRI is the preferred method
  • Alternatives include contrast-enhanced mammography or ultrasound if MRI is not possible 1

Higher-Risk Populations

• Black women and women of Ashkenazi Jewish heritage:

  • Should undergo risk assessment by age 25
  • May require earlier and more intensive screening based on risk factors 1

• Women with previous breast biopsy showing atypical hyperplasia:

  • More likely to benefit from regular mammography
  • Should consider supplemental MRI screening 1, 2

Clinical Breast Examination and Self-Examination

• Clinical breast examination is not recommended for breast cancer screening among average-risk women 1
• Breast self-examination is not recommended due to risk of false positives and lack of evidence of benefit 1
• Instead, breast self-awareness (understanding normal appearance and feel) is encouraged 1

Follow-up of Abnormal Results

Timely follow-up of abnormal screening results is crucial:

• For high-suspicion findings, diagnostic testing should occur sooner than for less suspicious results
• Delays beyond one year in diagnostic follow-up are associated with increased odds of larger tumors and lymph node metastases 3

Common Pitfalls to Avoid

• Failure to conduct risk assessment by age 25 for high-risk women 1
• Continuing screening in women with life expectancy less than 10 years 1
• Relying solely on mammography for high-risk women or those with dense breasts 1
• Having a false sense of security from false-negative results, particularly in dense breast tissue 1
• Delaying follow-up of abnormal results, which can lead to diagnosis of more advanced disease 3

Benefits vs. Harms of Screening

• Benefits: Early diagnosis, less aggressive therapy, improved cosmetic results, and reduced mortality (24% mortality reduction) 1
• Harms: Increased biopsy rates, psychological effects of false-positive results, and unnecessary procedures 4

The evidence strongly supports the value of regular mammography screening in reducing breast cancer mortality, particularly for women aged 50 and older, while recognizing the importance of individualized risk assessment to determine optimal screening approaches for women at higher-than-average risk.