The superior vena cava syndrome: clinical characteristics and evolving etiology.

Malignancy is the most common cause of the superior vena cava (SVC) syndrome. With the increasing use of intravascular devices, the incidence of the SVC syndrome arising from benign etiologies is increasing. We reviewed the etiology and outcome of 78 patients with SVC syndrome over 5 years. Malignancy was the etiology in 60% of the cases, and bronchogenic carcinoma was the most common malignancy. Small cell and non-small cell lung cancer accounted for 17 (22%) and 19 (24%) cases, respectively, but a higher percentage of patients with small-cell lung cancer developed the syndrome (6% vs 1%). Lymphoma and germ cell tumors were other significant malignant causes (8% and 3% of cases, respectively). An intravascular device was the most common etiology in benign cases (22 of 31 cases; 71%), with fibrosing mediastinitis the second most common benign etiology (6 cases). The most frequent signs and symptoms were face or neck swelling (82%), upper extremity swelling (68%), dyspnea (66%), cough (50%), and dilated chest vein collaterals (38%). Dyspnea at rest, cough, and chest pain were more frequent in the patients with malignancy. Procedures performed for diagnostic or treatment purposes did not increase morbidity or mortality.