To the Editor.— The article by Lokich and Goodman contains a number of statements that are either controversial or unclear. Early in the article, venography, venous pressure measurements, and, indeed, efforts to obtain a specific diagnosis by tissue biopsy are labeled as dangerous. The authors indicate that the various diagnostic procedures may lead to life-threatening complications such as respiratory obstruction, aspiration, and hemorrhage. Although it is understandable that there is an increased incidence of hemorrhage in SVCS, they cite no evidence that respiratory obstruction or aspiration is more likely to occur in this condition than in any type of lung or mediastinal tumor. In fact, why respiratory obstruction should occur is not explained. The condemnation of venography is given without citing a single reference. Howard 1(p42) indicates that venography is well tolerated in SVCS. The article also tends to discourage attempts to obtain cytological or histological proof of tumor, by