How does breast pain present in breast cancer?

Breast Pain in Breast Cancer: Presentation Characteristics

Breast pain is not a common symptom of breast cancer, with only 0-3% of patients presenting with isolated breast pain having malignancy. 1 However, when breast cancer does present with pain, it has specific characteristics that warrant attention.

Types of Breast Pain in Cancer

• Advanced breast cancers may present with breast pain as the only symptom, especially when tumors are located deep in large breasts or have chest wall invasion 1
• Certain breast cancer subtypes are disproportionately associated with pain:
  • Invasive lobular carcinoma 1
  • Anaplastic carcinoma 1
  • Adenoid cystic carcinoma 1

Characteristics of Cancer-Related Breast Pain

• Cancer-related breast pain is typically:
  • Noncyclical (not related to menstrual cycle) 1
  • Unilateral (affecting one breast) 1
  • Focal (well-localized to a specific area) 1
  • Persistent rather than intermittent 1
  • Often located in the subareolar area, nipple, or lower inner breast 1

Risk Factors and Duration

• Some studies suggest that prolonged breast pain may indicate increased cancer risk:
  • 2.1-3.6 times increased risk for breast cancer in women with persistent pain 1
  • 5-fold increase in breast cancer risk for pain persisting more than 97 months 1
  • 5-fold increase after 37 months of pain 1
• However, other studies show no increased or even decreased risk of malignancy in patients with breast pain 1

Differentiating Features from Benign Breast Pain

• Benign breast pain is more commonly:
  • Cyclical (70% of cases) - related to hormonal fluctuations 2, 3
  • Bilateral or diffusely distributed 2
  • Waxes and wanes with menstrual cycle 2
• Noncyclical benign pain (25% of cases) may be inflammatory rather than hormonal 2

Post-Treatment Breast Cancer Pain

• Persistent pain following breast cancer treatment is common 4
• Post-mastectomy pain syndrome can result from:
  • Intercostobrachial nerve injury 5
  • Intercostal neuromas 5
  • Phantom breast pain 5
  • Pectoralis minor syndrome 5
• Treatment-related pain sources include:
  • Radiation-induced pain 6
  • Chemotherapy-induced pain 6
  • Surgical pain 6
  • Lymphedema-associated pain 4

Clinical Implications

• Focal, noncyclical breast pain warrants appropriate diagnostic imaging:
  • Diagnostic mammography with ultrasound for women ≥30 years 7
  • Ultrasound for women <30 years 7
• Even with normal clinical examination, imaging may be warranted for focal pain to exclude underlying malignancy 1, 7
• For diffuse, noncyclical pain without other symptoms, reassurance may be sufficient 3

Important Pitfalls to Avoid

• Dismissing focal, persistent breast pain without proper evaluation, as some cancers can present with pain as the only symptom 1, 3
• Assuming all breast pain is benign, particularly when pain is focal and persistent 1
• Failing to consider that localized pain can be a presenting symptom of breast cancer requiring careful physical and mammographic examination 8
• Ordering unnecessary imaging for diffuse, non-focal breast pain when clinical exam is normal 3

Understanding these characteristics can help differentiate between benign breast pain and pain potentially associated with breast cancer, guiding appropriate evaluation and management.