What tests should be ordered for a patient with axillary pain radiating to the left breast?

Diagnostic Approach for Axillary Pain Radiating to Left Breast

For a patient with axillary pain radiating to the left breast, age-appropriate diagnostic imaging is recommended, with ultrasound as the primary modality for all ages, plus mammography for patients ≥30 years of age. 1

Initial Diagnostic Workup

For patients ≥30 years of age:

• Ultrasound of the axilla and breast - First-line imaging test 1
• Diagnostic mammography or digital breast tomosynthesis (DBT) - Should be performed in conjunction with ultrasound 1

For patients <30 years of age:

• Ultrasound of the axilla and breast only - Mammography is not recommended 1, 2

Imaging Interpretation and Follow-up

If imaging findings are normal (BI-RADS 1):

• Provide reassurance and symptomatic management:
  • Over-the-counter pain medications
  • Good support bra
  • Ice packs or heating pads 2

If imaging reveals a simple cyst (BI-RADS 2):

• If the cyst correlates with the focal pain, drainage may be considered for symptom relief 2

If imaging reveals a complicated cyst (BI-RADS 3):

• Follow-up imaging every 6 months for 1-2 years
• Symptomatic management as needed 2

If imaging is suspicious (BI-RADS 4 or 5):

• Core needle biopsy is recommended 2, 1
• For suspicious axillary lymph nodes, ultrasound-guided core needle biopsy should be performed 1

Special Considerations

• If axillary biopsy confirms metastatic disease of breast origin but breast imaging is negative, breast MRI should be performed 2, 1
• If lymphoma is suspected in axillary lymph nodes, special pathologic evaluation and/or surgical excision may be required 2
• For palpable axillary mass with negative/benign imaging, clinical management should be based on level of suspicion 2

Important Clinical Considerations

• The risk of cancer in a woman presenting with breast pain as the only symptom is low (1.2%-6.7%) 2
• Axillary masses are more often related to benign disorders than malignancy 2
• However, when cancer is identified in axillary lymph nodes, breast cancer is the most common cause 2
• Consider non-breast etiologies such as:
  • Infections or inflammatory conditions
  • Accessory breast tissue disorders (can present as axillary masses) 3
  • Brachial plexus disorders (can cause radiating pain) 4

Common Pitfalls to Avoid

• Failing to perform breast imaging even with isolated axillary symptoms, as occult breast cancer is a common cause 1
• Relying solely on mammography, as ultrasound is superior for characterizing axillary findings 1
• Missing non-breast etiologies such as systemic diseases, lymphoma, and other malignancies 1
• Observation alone without appropriate imaging - studies show poorer outcomes for patients with occult breast cancer who undergo observation versus definitive treatment 5

By following this diagnostic algorithm, clinicians can effectively evaluate axillary pain radiating to the left breast while ensuring appropriate detection of potentially serious underlying conditions.