What is the recommended management for atypical lobular hyperplasia (ALH)?

Management of Atypical Lobular Hyperplasia (ALH)

For most cases of atypical lobular hyperplasia (ALH) that are incidental, limited in extent (≤3 foci), and concordant with imaging findings, close observation with surveillance is appropriate rather than surgical excision.

Diagnosis and Initial Management

Core Needle Biopsy Findings

• ALH is typically an incidental finding on core needle biopsy performed for other reasons
• ALH is characterized by proliferation of cells within the terminal duct lobular units of the breast 1
• When ALH is diagnosed on core needle biopsy, the following factors should be assessed:
  • Extent of ALH (number of foci)
  • Presence of other high-risk lesions
  • Radiologic-pathologic concordance

Management Algorithm Based on Biopsy Findings

1. Limited ALH (≤3 foci) with radiologic-pathologic concordance:

   • Observation is appropriate without surgical excision 2, 3
   • This represents a shift from older guidelines that recommended excision of all atypical lesions

2. ALH requiring surgical excision:

   • ALH involving >4 terminal ductal units 1
   • Radiologic-pathologic discordance 4
   • Pleomorphic variant of ALH 1
   • ALH with other high-risk lesions requiring excision 4

Risk Assessment and Surveillance

Breast Cancer Risk

• ALH confers a 4-5 fold increased lifetime risk of breast cancer compared to the general population 1
• Risk is approximately 0.5-1.0% per year 1
• Risk is bilateral (not limited to the breast where ALH was found) 1, 5
• Risk persists long-term, with many subsequent cancers occurring >15 years after diagnosis 1, 5
• Risk is doubled with positive family history of breast cancer 1

Surveillance Recommendations

• Clinical breast examination every 6-12 months 1
• Annual diagnostic mammography 1
• Consider supplemental screening with breast MRI for women with dense breasts 4, 1
• Surveillance must be bilateral as risk affects both breasts 1
• Long-term surveillance is essential as risk persists for decades 1, 5

Risk Reduction Strategies

Chemoprevention

• All women with ALH should be informed about chemoprevention options 1
• For premenopausal women: Tamoxifen 20mg daily for 5 years reduces invasive breast cancer risk by approximately 43-46% 1, 6
• For postmenopausal women: Either tamoxifen or raloxifene may be considered 1, 7
• Raloxifene is indicated for reduction in risk of invasive breast cancer in postmenopausal women at high risk, including those with atypical hyperplasia 7

Surgical Options

• Bilateral risk-reduction mastectomy is generally not recommended for ALH alone 1
• May be considered in special circumstances:
  • BRCA1/2 mutations
  • Strong family history of breast cancer
  • Patient preference after thorough counseling

Lifestyle Modifications

• Maintain healthy weight
• Limit alcohol consumption
• Regular physical activity
• Consider limiting hormone replacement therapy

Common Pitfalls to Avoid

1. Overtreatment: Not all ALH requires surgical excision; limited ALH (≤3 foci) with radiologic-pathologic concordance can be safely observed 2, 3

2. Inadequate follow-up: The risk of breast cancer persists long-term, requiring consistent surveillance for decades 1, 5

3. Failure to discuss risk reduction: All women with ALH should be informed about chemoprevention options 1

4. Unilateral focus: Surveillance must be bilateral as risk affects both breasts 1, 5

5. Misclassification: Ensure thorough pathologic review to distinguish ALH from other atypical lesions or early invasive carcinoma 1

6. Underestimating long-term risk: The risk of developing breast cancer remains elevated for at least 15-20 years after diagnosis 1, 5