Superior Vena Cava Syndrome—A Proposed Classification System and Algorithm for Management

Abstract

Superior vena cava (SVC) syndrome has a characteristic and often striking clinical presentation, which can occasionally be life threatening. It is caused by obstruction of the SVC either by extrinsic compression or internal thrombus. Clinical signs include cyanosis, plethora, distention of subcutaneous vessels, and edema of the arms, head and neck. Edema may compromise the function of the larynx or pharynx, causing dyspnea, stridor, cough, hoarseness, and dysphagia. A more serious sequela is cerebral edema, causing headaches, confusion, and possibly coma. Cardiac output may be diminished transiently by acute SVC obstruction. However, within a few hours, the increased venous pressure forces blood through collaterals so that a steady state of blood return is once again achieved. Evidence of hemodynamic compromise is usually a result of mass effect on the heart itself rather than the SVC compression.1–5 Traditionally, SVC syndrome has been viewed as a relative emergency. However, a recent review of data6 reveals that in most instances the course is relatively benign, and in fact often improves without any active treatment.5 Which patients require urgent intervention and which patients require little specific treatment for SVC syndrome has not been well defined. There are no detailed guidelines addressing the management of SVC obstruction. Though a general recommendation supporting the consideration of radiotherapy and/or stent placement for symptomatic SVC obstruction from lung cancer has been made both by the American College of Chest Physicians and the National Comprehensive Cancer Network, specific recommendations are currently lacking. Definition of the management is particularly important as the spectrum of possible interventions has increased, from radiotherapy and chemotherapy to thrombolytics and SVC stenting. Definition of a nuanced approach to patients with SVC syndrome has been hampered by lack of a method to describe variations in the presentation of such patients. The purpose of this article is to propose a classification scheme for patients with SVC obstruction according to the severity of symptoms. This in turn provides a basis for a treatment algorithm, matching different interventions with the severity of symptoms to define a rational framework of how to approach these patients.