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Superior vena cava syndrome
Obstruction of the superior vena cava causes facial and arm swelling and prominent chest veins; in most cases there is time to obtain a tissue diagnosis before treatment, and only a patient with stridor, laryngeal oedema or cerebral oedema needs an endovascular stent at once.
Why it matters in the exam
Superior vena cava syndrome appears in the exam in two scenarios: a patient without an oncologic history who presents with facial swelling and dyspnoea, and a patient with known lung cancer. The question tests whether the candidate knows not to rush to radiation or steroids before a diagnosis, and when a stent is the first treatment.
Remember that the common malignant cause is lung cancer, then lymphoma, and that there is a growing benign cause — thrombosis around a central catheter or pacemaker. Treatment is set by histology: chemosensitive tumours (small cell, lymphoma, germ cell) respond fast to chemotherapy, whereas in other tumours a stent gives much faster relief than radiation.
Key points
- The common malignant cause of superior vena cava syndrome is lung cancer, followed by lymphoma.
- In most patients the condition allows a tissue diagnosis before any treatment, and radiation or steroids must not come first.
- Stridor, laryngeal oedema or reduced consciousness require an endovascular stent at once.
- Definitive treatment is set by histology: chemotherapy in small cell, lymphoma and germ cell tumours, and radiation or stent in NSCLC.
- Thrombosis around a central catheter is a common benign cause treated with anticoagulation and sometimes catheter removal.
Summary table
| Issue | What to know | Exam detail |
|---|---|---|
| Causes | Lung cancer (most cases), lymphoma, germ cell tumours and thymoma | Benign cause: thrombosis around a central catheter or pacemaker |
| Presentation | Swelling of the face, neck and arms, dilated chest veins, dyspnoea, worse lying down or bending | Danger signs: stridor, laryngeal oedema, confusion or reduced consciousness |
| Work-up | Contrast chest CT, then tissue diagnosis (EBUS, node biopsy or guided biopsy) | Radiation or steroids before biopsy may obscure a lymphoma diagnosis |
| Life-threatening situation | Endovascular stent at once | Relief within hours to days |
| Treatment by histology | Small cell, lymphoma or germ cell — chemotherapy; NSCLC — radiation or stent then definitive treatment | Radiation relieves within weeks, so with severe symptoms a stent is preferred |
| Catheter-related thrombosis | Anticoagulation, and sometimes catheter removal | Local thrombolysis in selected cases |
| Supportive measures | Raise the head of the bed, oxygen as needed | Steroids — in lymphoma and thymoma, or for oedema around radiation |
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Sources
- NCCN Clinical Practice Guidelines in Oncology: Non-Small Cell and Small Cell Lung Cancer, 2026 — Management of superior vena cava obstruction
- Wilson, Detterbeck and Yahalom, Superior vena cava syndrome with malignant causes, New England Journal of Medicine, 2007 — Clinical practice review
- DeVita, Hellman and Rosenberg's Cancer: Principles and Practice of Oncology, 12th ed. (2023) — Oncologic emergencies
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.