What are the implications of atypical ductal hyperplasia (ADH) of the breast?

From the Guidelines

Breast atypical ductal hyperplasia (ADH) requires surgical excision for definitive diagnosis and management, and patients should undergo risk assessment and be considered for risk-reducing medications and enhanced surveillance to reduce breast cancer risk. When ADH is found on core needle biopsy, a surgical excisional biopsy should be performed since approximately 15-30% of these lesions are upgraded to ductal carcinoma in situ (DCIS) or invasive breast cancer upon complete removal 1. After diagnosis, patients should undergo risk assessment and be considered for risk-reducing medications such as tamoxifen 20mg daily, raloxifene 60mg daily, or aromatase inhibitors like exemestane 25mg daily or anastrozole 1mg daily for 5 years, as these can reduce breast cancer risk by 50-65% 1. Some key points to consider in the management of ADH include:

• Enhanced surveillance is recommended with annual mammography and clinical breast exams every 6-12 months 1.
• Patients should be counseled that ADH increases breast cancer risk approximately 4-5 times compared to the general population, with the highest risk in the first 5-10 years after diagnosis 1.
• This elevated risk applies to both breasts, not just the affected side.
• Lifestyle modifications including maintaining healthy weight, limiting alcohol consumption, and regular exercise should also be encouraged as these can help reduce overall breast cancer risk 1. It is also important to note that low-dose tamoxifen (5mg daily) may be an alternative for women with intraepithelial neoplasia, as it has been shown to reduce breast cancer risk with fewer side effects compared to standard-dose tamoxifen 1. Overall, the management of ADH should prioritize risk reduction and surveillance to minimize the risk of breast cancer development.

From the Research

Implications of Atypical Ductal Hyperplasia (ADH) of the Breast

The implications of ADH of the breast are significant, with an increased risk of subsequent carcinoma. Some key points to consider include:

• ADH is associated with a substantial increase in lifetime risk for breast cancer 2
• The risk of upgrade to invasive cancer after surgery and the risk of progression to invasive cancer for ductal carcinoma in situ (DCIS) are concerns 3, 4
• Certain radiological and cytological criteria can be used to help determine which patients should forgo surgery and be followed up with good results 3
• Long-term follow-up is crucial for patients who have not undergone surgery 3
• Active surveillance (AS) with imaging may be a viable option for some patients with ADH and DCIS, reducing the burden of overtreatment 4

Management Strategies

Management strategies for ADH include:

• Surgical excision, which may reveal invasive carcinoma or high-grade DCIS 3, 5
• Active surveillance with imaging, which may be appropriate for select patients 4
• Risk-reducing strategies, such as preventive endocrine therapy options, enhanced surveillance imaging, and lifestyle modifications 2
• Consideration of molecular markers and laboratory updates, such as EZH2 overexpression, to help identify which cases of ADH will be upgraded to carcinoma 6

Clinical Significance

The clinical significance of ADH is notable, with:

• An increased risk of subsequent carcinoma when diagnosed in isolation 6
• Variable clinical significance when ADH involves benign breast lesions 6
• Challenges in obtaining an accurate diagnosis of clinically palpable and multicentric ADH or DCIS based on preoperative radiological and histological evaluation 5