Superior vena cava syndrome induced by bronchogenic carcinoma: is this an oncological emergency?

This study was initiated to assess the validity of the traditional view that superior vena cava syndrome (SVCS) induced by bronchogenic carcinoma is a life-threatening condition requiring immediate treatment without necessarily obtaining a tissue diagnosis. A retrospective review of 6504 patients diagnosed to have lung cancer and treated at the Queensland Radium Institute between 1979 and 1991 was performed. From this group, 249 patients with well-documented SVCS treated with radiotherapy were identified. An analysis with respect to duration of symptoms, time to treatment, degree of response and overall survival was performed. Although deaths did occur in this series due to associated tracheal obstruction, deaths due to venous compression per se were not seen. The response to radiotherapy was generally poor, with only 19% of patients achieving a complete resolution of their symptoms and signs while 30% of patients had no demonstrable response. The overall survival of patients in the study group was 5% at two years. The median survival for complete responders was 6 months while for non-responders it was 1 month. This study found little evidence to support the concept that SVCS is an oncological emergency. Patients survived despite unrelieved obstruction and the data suggest that the poor prognosis of patients with this condition appears to more closely correlate with the prognosis of the underlying disease. It is suggested that intravascular thrombosis may be an important factor in the pathogenesis of this syndrome. 16 refs., 5 tabs., 5 figs