What pre-blood work is recommended prior to initiating raloxifene (Evista) therapy for chemoprevention?

Pre-Blood Work Requirements for Raloxifene in Chemoprevention

No specific pre-blood work is mandated by guidelines before initiating raloxifene for breast cancer chemoprevention, but a baseline assessment of venous thromboembolism risk factors is essential due to raloxifene's increased risk profile for this complication. 1

Risk Assessment Before Initiating Raloxifene

Raloxifene is FDA-approved for reducing the risk of invasive breast cancer in postmenopausal women with osteoporosis and/or postmenopausal women at increased risk of breast cancer. Before prescribing raloxifene for chemoprevention, consider:

Patient Selection Criteria

• Confirm the patient is postmenopausal (raloxifene should not be used in premenopausal women) 1
• Verify 5-year projected absolute breast cancer risk ≥1.66% or presence of lobular carcinoma in situ (LCIS) 1
• Ensure no history of thromboembolic events (contraindication) 1

Risk Assessment

While no specific blood tests are mandated by guidelines, clinical judgment suggests evaluating:

1. Thromboembolic Risk Factors:

   • Raloxifene increases risk of venous thromboembolism with a relative risk of 3.1 compared to placebo 1, 2
   • Contraindicated in women with history of deep vein thrombosis, pulmonary embolism, stroke, or transient ischemic attack 1

2. Baseline Health Status:

   • Consider standard health assessment that might include complete blood count and comprehensive metabolic panel to establish baseline health status
   • No specific laboratory monitoring is required by guidelines for chemoprevention use 1

Monitoring During Raloxifene Therapy

• No specific ongoing blood monitoring is required for chemoprevention use
• Timely workup of any abnormal vaginal bleeding 1
• Regular clinical follow-up to assess for adverse effects

Important Considerations

Benefits vs. Risks

• Raloxifene reduces risk of invasive breast cancer by 76% over 3 years in postmenopausal women 3
• Most significant for estrogen receptor-positive breast cancers (90% risk reduction) 3
• Consider risk-benefit profile - studies show approximately 5% of raloxifene users may not have evidence of net benefit 4

Adverse Effects to Monitor

• Hot flushes and leg cramps are common side effects 5, 6
• Increased risk of venous thromboembolic events (RR 3.1) 2
• Unlike tamoxifen, raloxifene does not increase endometrial cancer risk 3

Duration of Therapy

• Standard recommendation is 60 mg daily orally for 5 years 1
• May be used longer than 5 years in women with osteoporosis, where breast cancer risk reduction is a secondary benefit 1

Comparison with Other Agents

Unlike some other medications used for osteoporosis or breast cancer prevention, raloxifene does not require specific pre-treatment laboratory testing when used for chemoprevention. This contrasts with agents like bisphosphonates which often require baseline renal function assessment.

In summary, while no specific pre-blood work is mandated by guidelines for raloxifene when used for chemoprevention, clinical judgment should guide assessment of thromboembolic risk factors and baseline health status before initiating therapy.