上腔靜脈症候群

Buzzwords → Dx

Diagnostic Criteria

• Clinical: facial / neck / arm swelling + dilated collaterals + dyspnea + Pemberton sign (face flushes when arms raised).
• CT chest with IV contrast confirms obstruction + identifies cause.
• Tissue diagnosis (biopsy) before treatment unless emergent airway / cerebral edema.

Workup

• CT chest + neck with contrast — confirms SVC obstruction, defines extent, identifies tumor.
• CXR (mediastinal mass, pleural effusion).
• Tissue diagnosis by least-invasive route: sputum cytology → bronchoscopy → mediastinoscopy → CT-guided biopsy. Lymph node excision if accessible.
• Echo to assess cardiac function (some malignant SVC have pericardial effusion + tamponade overlap).
• Doppler / venogram of upper extremity if catheter-related thrombosis suspected.
• Coagulation panel before invasive procedures.

Treatment Algorithm

flowchart TD
  A[Suspected SVC syndrome] --> B[CT chest + neck with contrast]
  B --> C{Severity}
  C -- airway / cerebral edema --> D[Emergent intervention<br>endovascular stent + steroids<br>biopsy AFTER stabilization]
  C -- non-emergent --> E[Pursue tissue diagnosis FIRST<br>then disease-specific treatment]
  E --> F{Tumor type}
  F -- SCLC / lymphoma (radiosensitive) --> G[Systemic chemotherapy ± RT<br>often sufficient without stent]
  F -- NSCLC --> H[Stenting often used + chemo/RT/IO]
  F -- catheter thrombosis --> I[Anticoagulation + remove catheter or thrombolysis<br>± stent if persistent obstruction]
  D --> J[Diuretics + head-of-bed elevation + supportive O₂]
  G --> J
  H --> J
  I --> J

Pearls / Pitfalls

• Get a tissue diagnosis BEFORE empiric treatment unless emergent (airway, cerebral edema). Steroids before biopsy can render lymphoma biopsy non-diagnostic.
• Endovascular stenting is first-line for rapid relief of malignant SVC syndrome — can be done in <24 h with experienced IR. Often combined with chemo / RT.
• SCLC + SVC → systemic chemo (etoposide-platin) usually resolves without stenting.
• Lymphoma + SVC → R-CHOP / DA-EPOCH-R typically resolves; mediastinal RT considered only after chemo response.
• Catheter-related SVC thrombosis — anticoagulation; thrombolysis if extensive; remove catheter if not essential, or attempt salvage with anticoag.
• Avoid IV access in upper extremities during SVC syndrome (poor return; risk of extravasation) — use lower extremity or central femoral access.
• Don't sit patient supine — head-up positioning helps. Diuretics may briefly help (caution: dehydration worsens prognosis if cancer-related).
• SVC syndrome from indwelling lines is increasingly common (catheters, ports, ICDs) — counsel + screen for symptoms.
• Cerebral edema → stenting + steroids urgently.
• Recurrent SVC syndrome in cancer survivor → fibrosis from prior RT or recurrent disease — venogram + stent.

Cross-references

• DLBCL — primary mediastinal mass
• VTE — catheter-related thrombosis
• Cord compression — concurrent oncologic emergency
• Drug Regimens — chemo + steroids

相關題目

• Q-187 — SVC syndrome — initial workup
• Q-188 — SVC — emergent stenting
• Q-189 — SVC syndrome from primary mediastinal B-cell lymphoma (PMBL)

Sources