From the Guidelines
Atypical Ductal Hyperplasia (ADH) confers a significantly increased risk of breast cancer, with a relative risk of 4- to 5-fold for invasive cancer, and a cumulative risk 10 years after diagnosis that is 2.6 times higher than without ADH. Women diagnosed with ADH have approximately a 4-5 times higher risk of developing breast cancer compared to women without ADH, which translates to about a 20-30% lifetime risk of developing breast cancer following an ADH diagnosis 1. The risk is bilateral, meaning it affects both breasts, even if ADH was only found in one breast. This elevated risk persists long-term and does not diminish substantially over time. Key factors to consider in assessing the risk include:
- The number of family members with breast cancer, especially first-degree relatives, and their age at diagnosis
- Personal history of breast cancer or other proliferative breast lesions
- Genetic predisposition, such as BRCA1 or BRCA2 mutations
- History of radiation therapy, particularly at a young age
- Ethnicity, with black women experiencing higher incidence rates of triple-negative breast cancer
For patients diagnosed with ADH, enhanced surveillance is typically recommended, including annual mammography, possible breast MRI depending on other risk factors, and consideration of chemoprevention options such as tamoxifen, raloxifene, or aromatase inhibitors. Risk-reducing strategies should be discussed with healthcare providers, as individual risk may vary based on additional factors such as family history, genetic predisposition, and other breast pathologies 1. It is essential to weigh the benefits and risks of these strategies, considering the potential impact on morbidity, mortality, and quality of life.
From the Research
Risk of Breast Cancer in Patients with ADH
The risk of breast cancer in patients with Atypical Ductal Hyperplasia (ADH) is a significant concern. Studies have shown that ADH is a high-risk premalignant lesion of the breast, and its biology is poorly understood 2.
Key Findings
- ADH is associated with an increased risk of developing breast cancer, with a 2:1 ratio of ipsilateral to contralateral breast cancer 2.
- The ipsilateral predominance is marked in the first 5 years, consistent with a precursor phenotype for ADH 2.
- The 10-year cumulative risk of invasive breast cancer after a diagnosis of ADH is approximately 2.6 times higher than the risk in women with no ADH 3.
- ADH diagnosed via excisional biopsy is associated with an adjusted hazard ratio (HR) of 3.0, and via core needle biopsy, with an adjusted HR of 2.2 3.
- The estimated 10-year breast cancer risk for women with ADH is around 17.3% 4.
Management and Follow-up
- Chemoprevention has been shown to significantly reduce breast cancer risk for all atypia types, including ADH 4.
- Long-term follow-up is crucial for patients with ADH, especially those who have not undergone surgery 5.
- Certain radiological and cytological criteria can be used to help determine which patients should forgo surgery and be followed up with good results 5.
Risk Estimates
- The risk of breast cancer with atypical breast lesions, including ADH, is substantial, with estimated 10-year cancer risks ranging from 17.3% to 26.0% 4.
- Women with ADH diagnosed on excisional biopsy have a slightly higher risk of invasive cancer compared to those with ADH diagnosed via core needle biopsy 3.