Respiratory · Year 1 · from Respiratory
Case 2: Malignant Pleural Effusion
Clinical Image
Source: Wikimedia Commons - Malignant pleural effusion - CC BY-SA 3.0
Patient Presentation
A 68-year-old woman with a history of breast cancer treated 5 years ago presents with progressive dyspnea over 6 weeks. She denies fever or cough but reports mild right-sided chest discomfort. She has lost 10 pounds unintentionally over the past 2 months. Her breast cancer was ER/PR positive and was treated with mastectomy and tamoxifen.
Demographics
- Age: 68 years
- Sex: Female
- Past Medical History: Stage II breast cancer (right mastectomy 5 years ago), completed adjuvant therapy
- Medications: Previously on tamoxifen, completed 5 years ago
- Family History: Sister with breast cancer
Chief Complaint
Progressive dyspnea and weight loss
Physical Examination
- Temperature: 36.8°C
- Blood pressure: 118/72 mmHg
- Heart rate: 88 bpm
- Respiratory rate: 22/min
- Oxygen saturation: 93% on room air
- General: Thin, appears mildly dyspneic
- Respiratory:
- Dullness to percussion right hemithorax from base to mid-lung
- Markedly decreased breath sounds right lower two-thirds
- Trachea midline
- Chest wall: Right mastectomy scar, no chest wall masses
- No palpable lymphadenopathy
Workup
- Chest X-ray: Large right pleural effusion occupying approximately two-thirds of hemithorax
- CT chest: Large right pleural effusion with nodular pleural thickening, no lung mass, no mediastinal adenopathy
- Thoracentesis (1.5 L removed with symptomatic relief):
- Appearance: Bloody (serosanguinous)
- Light's criteria: Exudate
- Cell count: 2,800/μL (85% lymphocytes)
- Glucose: 45 mg/dL (low)
- pH: 7.28 (low)
- Cytology: Positive for adenocarcinoma, consistent with breast primary (ER positive)
- PET-CT: FDG-avid pleural disease, bone metastases (spine, pelvis)
Diagnosis
Malignant Pleural Effusion from Metastatic Breast Cancer
Treatment
- Symptomatic management: Therapeutic thoracentesis provided relief
- Long-term management options (discussed with patient):
- Indwelling pleural catheter (IPC): Allows home drainage, quality of life focus
- Pleurodesis (talc via chest tube or VATS): For patients with good performance status and expected survival >3 months
- Systemic therapy: Restart endocrine therapy (aromatase inhibitor +/- CDK4/6 inhibitor) for ER+ metastatic disease
- Palliative care consultation for goals of care discussion
- Bone-directed therapy for skeletal metastases
Physiological Principles Demonstrated
- Malignant effusion mechanisms: Tumor on pleural surfaces blocks lymphatic drainage (main mechanism), direct pleural invasion increases capillary permeability, and tumor can obstruct mediastinal lymphatics.
- Cytology sensitivity: First thoracentesis cytology is approximately 60% sensitive; repeat increases yield to 80%. Thoracoscopic biopsy exceeds 90%.
- Lymphocyte predominance: Malignant and tuberculous effusions typically show lymphocyte predominance, unlike parapneumonic effusions (neutrophil predominant).
- Prognosis: Malignant pleural effusion represents stage IV disease (median survival varies by primary: 3-12 months for most solid tumors, longer for breast cancer with hormone-sensitive disease).