What is the next recommended test or imaging study for a patient with persistent left submammary pain, normal mammography, and normal chest X-ray and ultrasound, who is a smoker?

Next Steps for Persistent Left Submammary Pain with Normal Initial Imaging

For a patient with persistent left submammary pain for 3 months who is a smoker with normal mammogram, chest X-ray, and ultrasound, the next recommended test is an upper gastrointestinal endoscopy to evaluate for gastroesophageal reflux disease (GERD) or other gastrointestinal causes.

Rationale for Recommendation

Ruling Out Cardiac Causes

1. With normal chest X-ray and no reported chest pain or breathing issues, cardiac causes are less likely but still warrant consideration given the patient's smoking history.
2. The location (below left breast) and chronicity (3 months) without associated cardiac symptoms makes acute coronary syndrome less likely 1.

Ruling Out Breast Pathology

1. Normal mammogram and ultrasound of the area effectively rule out breast-related causes:
   • The ACR Appropriateness Criteria for Breast Pain indicates that breast cancer is rare (0-3%) in patients with breast pain as their only symptom 1.
   • With normal imaging already completed, additional breast imaging (MRI, tomosynthesis) is not indicated 1.

Considering Non-Cardiac, Non-Breast Causes

1. Gastrointestinal causes are a common source of chest wall pain that can mimic cardiac or breast pathology:

   • For patients with recurrent acute chest pain without evidence of cardiac or pulmonary causes, evaluation for gastrointestinal causes is reasonable (Class 2a, Level C-LD) 1.
   • GERD and peptic ulcer disease can present with pain in the left submammary region 2, 3.
   • Studies show a high prevalence of esophagitis (52.3%) and peptic ulcer (8.4%) in patients with suspected GERD-related symptoms 2.

2. Smoking is a risk factor for both GERD and peptic ulcer disease:

   • Smokers have higher rates of peptic ulcer disease, which can present with epigastric or submammary pain 4.

Recommended Diagnostic Algorithm

1. Upper Gastrointestinal Endoscopy:

   • First-line next test to evaluate for GERD, esophagitis, or peptic ulcer disease 5.
   • High diagnostic yield in patients with persistent chest/epigastric pain and normal cardiac/pulmonary evaluation 2, 3.

2. If endoscopy is negative:

   • Consider CT chest with contrast to evaluate for:
     • Chest wall inflammatory conditions
     • Subtle pleural disease related to smoking history
     • Costochondral junction abnormalities 1

3. If both endoscopy and CT chest are negative:

   • Consider referral to pain management for evaluation of musculoskeletal causes
   • Bone scan may be considered if inflammatory conditions of the sternoclavicular joints or costochondral junctions are suspected 1

Important Considerations and Pitfalls

• Don't assume breast etiology: With normal mammogram and ultrasound, continued focus on breast imaging is unlikely to yield diagnosis 1.
• Don't dismiss symptoms in smokers: While smoking increases risk of serious conditions, attributing symptoms solely to smoking can lead to missed diagnoses.
• Consider referred pain: Submammary pain can originate from thoracic, abdominal, or musculoskeletal sources 1.
• Avoid premature closure: If initial GI evaluation is negative, continue systematic evaluation rather than labeling as non-specific pain.

By following this approach, you can efficiently identify the cause of persistent left submammary pain while minimizing unnecessary testing and addressing the most likely etiologies based on the patient's risk factors and presentation.