superior vena cava (SVC) syndrome

Introduction

Obstruction of blood flow through the superior vena cava.

Etiology

• lung cancer, especially small cell carcinoma (75%)
• Hodgkin's lymphoma
• mediastinal fibrosis
• radiation fibrosis
• other mediastinal tumors
  • thymoma
  • germ cell tumor
  • non-Hodgkin's lymphoma
• thrombosis
  • central venous catheters
  • implanted device (ICD)
• goiter compressing subclavian vein & jugular vein

Pathology

• 3 collateral venous pathways
  • azygous vein
  • internal thoracic vein
  • long thoracic vein
• when venous pathways overwelmed, venous pressures become elevated

Clinical manifestations

• insidious onset
• dyspnea is the most common presenting symptom
• dysphagia
• cough
• chest pain
• prominent collateral veins (venous distension) over the chest
• jugular venous distension
• facial edema, Pemberton's Sign
• fullness of the head, pethora
• headache
• arm swelling
• stridor (tracheal obstruction)

Diagnostic procedures

• bronchoscopy has a high yield & is generally safe
  • not safe [NEJM knowlege+]
• mediastinoscopy may be associated with excessive hemorrhage due to obstructed venous return but may have a higher diagnostic yield
  • complications 5%
• thorcentesis if pleural effusion
• biopsy of peripheral lymphadenopathy

Radiology

• computed tomography (CT of chest) with IV contrast (diagnostic test of choice)
  • mediastinal widening
  • pleural effusion may be present

Complications

• tracheal obstruction

Management

• generally NOT regarded as a medical emergency
• generally MORE IMPORTANT to establish tissue diagnosis
  • biopsy tissue external to obstructing mass
  • if no external tissue to biopsy, biopsy mediastinal mass
  • if tissue biopsy unsuccessful at establishing diagnosis, bronchoscopy, mediastinoscopy, thoracotomy
• treatment directed at specific etiology (type of cancer)
  • radiation therapy (mainstay of treatment)
    • palliation in 70% of patients with lung cancer & in 95% of patients with lymphoma
    • appropriate even with unstaged NSCLC
  • chemotherapy: small cell lung cancer, germ cell neoplasms, NSCLC
  • continuous infusion of heparin for thrombosis
• endovascular stenting
  • refractory disease, hempdynamic instability
  • rapid symptomatic improvement
  • warfarin 1 mg daily with goal of INR < 1.6 ??
• does not worsen prognosis of otherwise curable malignancies

More general terms

• syndrome

Additional terms

• superior vena cava (SVC)
• thoracic outlet syndrome

Patient information

superior vena cava (SVC) syndrome patient information