What are the management options for a patient with lobular neoplasia, atypical lobular hyperplasia, or lobular carcinoma in situ?

Management of Lobular Neoplasia (ALH/LCIS)

For patients with atypical lobular hyperplasia (ALH) or lobular carcinoma in situ (LCIS), annual screening mammography should begin immediately at diagnosis (but not before age 30), and supplemental annual breast MRI should be strongly considered given the 7-10 fold increased risk of developing invasive breast cancer. 1, 2

Risk Stratification and Surveillance

Breast Cancer Risk Assessment

• Lobular neoplasia (ALH and LCIS) confers a lifetime breast cancer risk of 10-20%, translating to a continuous annual risk of 0.5-1.0% per year 1
• LCIS specifically carries a 7-10 fold increased risk compared to the general population, with most invasive cancers occurring more than 15 years after diagnosis 1, 2
• The risk is bilateral, meaning both breasts remain at elevated risk indefinitely 1
• Risk doubles when there is an associated family history of breast cancer 1, 3

Screening Protocol

Annual mammography recommendations:

• Begin at time of diagnosis, but not before age 30 years 1, 4
• Digital breast tomosynthesis (DBT) is preferred over standard 2D mammography as it increases cancer detection rates by 20-40% and decreases false-positive recalls 1, 4
• Continue screening as long as life expectancy exceeds 5-7 years 1, 4

Supplemental MRI screening:

• Annual breast MRI with contrast is recommended starting at age 30 for women with biopsy-confirmed lobular neoplasia 1, 4
• MRI demonstrates 91-98% sensitivity for breast cancer detection in high-risk women when combined with mammography 4
• MRI is particularly valuable given that mammography may have lower specificity in women with ALH compared to average-risk women 4
• If MRI is unavailable, contraindicated, or declined, supplementary ultrasound in dense breasts should be considered 1

Surgical Management Decisions

When Core Needle Biopsy Shows Lobular Neoplasia

Classic ALH or LCIS (concordant with imaging):

• Imaging surveillance is acceptable in select cases where the finding is incidental, minimal, and concordant with imaging 1, 5
• Close observation may substitute for excisional biopsy in these carefully selected patients 1

Excisional biopsy is mandatory when:

• Pleomorphic LCIS variant is present (behaves more like DCIS) 1, 5, 6
• Clinical or radiological masses are detected (19% underestimation rate for invasive cancer) 6
• Imaging findings are discordant with pathology 1, 5
• The lesion is extensive or multifocal 4

Incidental LCIS Finding

• When LCIS is found incidentally on biopsy for another indication, risk-reducing mastectomy is not mandatory 1
• Options include ongoing surveillance (as outlined above) or chemoprevention, which should be discussed with the patient 1

Chemoprevention for Risk Reduction

Tamoxifen (First-Line Option)

Efficacy and indications:

• Tamoxifen provides a 75% reduction in invasive breast cancer occurrence in women with atypical hyperplasia 3, 7
• The NSABP Breast Cancer Prevention Trial demonstrated a 43-44% reduction in invasive breast cancer incidence overall, with even greater benefit in high-risk subgroups 7
• This represents Category 1 evidence (highest level) for risk reduction 3

Dosing and duration:

• 20 mg daily for 5 years 3, 7
• Treatment substantially reduces risk for both invasive cancer and benign breast disease 3

Monitoring requirements:

• Baseline and periodic gynecologic evaluation (increased endometrial cancer risk) 3
• Regular assessment for thromboembolic symptoms (DVT, PE risk) 3
• Monitor for vasomotor symptoms, muscle spasms, and gynecologic symptoms 3
• Assess for stroke risk factors, particularly in women with cardiovascular disease 7

Raloxifene (Alternative for Postmenopausal Women)

Indications:

• FDA-approved for reduction in risk of invasive breast cancer in postmenopausal women at high risk, including those with LCIS or atypical hyperplasia 8
• High risk is defined as at least one breast biopsy showing LCIS or atypical hyperplasia, one or more first-degree relatives with breast cancer, or 5-year predicted risk ≥1.66% by Gail model 8

Dosing:

• 60 mg daily, administered any time of day without regard to meals 8
• Optimum duration of treatment is not fully established, though studied for up to 5 years 8

Critical warnings:

• Increased risk of venous thromboembolism (DVT and PE) - contraindicated in women with active or past history of VTE 8
• Increased risk of death from stroke in postmenopausal women with documented coronary heart disease 8
• Consider risk-benefit balance carefully in women at risk for stroke 8

Long-Term Follow-Up

Lifelong surveillance is required regardless of surgical excision or chemoprevention:

• History and physical examination every 6-12 months for 5 years, then annually 3
• Annual diagnostic mammography (with DBT preferred) indefinitely 4, 3
• Annual breast MRI for at least 20 years, potentially longer 1
• Risk remains elevated in both breasts for decades, with median follow-up studies showing continued risk at 17 years 1, 3

Common Pitfalls to Avoid

• Do not stop screening at age 65-70 if the patient remains in good health; continue for at least 20 years after diagnosis even if this extends past typical screening age cutoffs 1
• Do not rely on mammography alone in these high-risk patients; supplemental MRI significantly improves cancer detection 1, 4
• Do not assume all lobular neoplasia requires excision after core biopsy; classic, concordant, minimal ALH/LCIS can be managed with surveillance in select cases 1, 5
• Do not overlook pleomorphic LCIS, which requires excision due to its DCIS-like behavior and higher upgrade rate 1, 5, 6
• Do not prescribe raloxifene to premenopausal women or those with history of VTE or significant stroke risk 8