What is the cause of bilateral mastalgia in a postmenopausal woman?

Causes of Postmenopausal Bilateral Mastalgia

Postmenopausal bilateral mastalgia is most commonly noncyclical in nature and requires evaluation to exclude underlying benign or malignant breast lesions, with the most frequent causes being duct ectasia with periductal inflammation (25% of cases), medication-related effects, extramammary chest wall conditions, and rarely, advanced breast cancer.

Primary Mammary Causes

Duct Ectasia and Periductal Inflammation

• Duct ectasia with periductal inflammation accounts for approximately 25% of noncyclical mastalgia cases in postmenopausal women 1
• This condition is strongly associated with heavy smoking and presents as focal, burning pain often behind the nipple 1, 2
• Mammography may reveal duct ectasia or secretory calcifications at the site of pain 3
• Smoking cessation is the primary intervention for this etiology 2, 4

Benign Breast Lesions

• Fibrocystic changes can persist into the postmenopausal period and cause bilateral pain 1
• Simple cysts may correlate with focal pain and can be drained for symptom relief 2
• Noncyclical mastalgia resolves spontaneously in up to 50% of cases without specific treatment 3, 5

Malignancy Considerations

• Advanced breast cancers can present with pain as the only symptom, particularly invasive lobular carcinoma and anaplastic carcinoma, which are disproportionately associated with mastalgia 3, 4
• The risk of cancer in women presenting with breast pain alone ranges from 1.2-6.7%, though this remains relatively low 2, 4
• Cancers deep in large breasts or with chest-wall invasion are more likely to present with pain 3
• Thorough evaluation to rule out malignancy is mandatory before attributing symptoms to benign causes 1

Medication-Related Causes

• Noncyclical breast pain due to various medications is poorly understood and has variable presentations 3
• Hormone replacement therapy can cause bilateral mastalgia in postmenopausal women 6
• One case report documented excessively elevated estradiol levels (peak 2325 pmol/l) causing sudden intense bilateral mastodynia in a postmenopausal woman 7

Extramammary (Referred) Causes

• Extramammary causes account for 10-15% of perceived "breast pain" and must be systematically excluded 3

Musculoskeletal Origins

• Tietze syndrome (costochondritis) affecting the chest wall 3
• Pectoral muscle strains or spasms 3
• Entrapment of the lateral cutaneous branch of the third intercostal nerve 3
• Fibromyositis, fibromyalgia, myalgia 3
• Rib fractures 3

Neurological Sources

• Spinal nerve root syndrome (cervical or thoracic) causing referred pain along intercostal nerves T3-T5 3
• Any irritation along the anterolateral and anteromedial branches of intercostal nerves can manifest as breast or nipple pain 3

Visceral Referred Pain

• Coronary ischemia (critical to exclude in postmenopausal women) 3
• Esophageal disease including achalasia and hiatal hernia 3
• Gastroesophageal reflux and peptic ulcer disease 3
• Pulmonary conditions such as pleurisy, pulmonary embolus, or tuberculosis 3
• Gallbladder pathology 3
• Shingles (herpes zoster) 3

Trauma and Surgical History

• Previous breast surgery can cause chronic pain, especially if complicated by postoperative infection, hematoma, or incisions across Langer lines of tension 3
• Breast implants, particularly subpectoral placement, are associated with pain 3
• Postsurgical pain may result from scar tissue, nerve regeneration, focal nerve injury from ischemia, radiation effects, lymphedema, or implant capsule formation 3
• Trauma-related noncyclical breast pain occurs in approximately 10% of cases 3

Critical Clinical Pitfalls

Common Diagnostic Errors

• Dismissing breast pain without proper evaluation, as some cancers present with pain alone 2
• Failing to consider extramammary causes when breast examination and imaging are normal 2
• Not obtaining age-appropriate imaging (diagnostic mammogram with ultrasound for women ≥30 years) to exclude malignancy 2, 4

Key Distinguishing Features

• Noncyclical mastalgia in postmenopausal women is typically unilateral and focal, but bilateral presentation can occur 3, 1
• Most cases do not respond to hormonal manipulation, unlike premenopausal cyclical mastalgia 3
• The presence of palpable masses, skin changes, or nipple discharge significantly increases cancer risk and mandates immediate diagnostic workup 4, 6

Management Approach

• Reassurance after excluding malignancy resolves symptoms in many cases 2, 4
• For persistent symptoms without identified pathology, consider cyclic danazol therapy for 3 months if fibrocystic changes are present 1
• NSAIDs provide symptomatic relief for inflammatory causes 2, 4
• Address smoking cessation for periductal inflammation 1, 2
• Properly fitted supportive bras can help with mechanical pain 2