LONG-TERM HAZARDS OF THOROTRAST

All patients (168) known to have received Thorotrast in the course of clinical investigation in a department of surgical neurology have been followed up and their current or final status at 1 January 1966 or later established. A total of 137 patients received Thorotrast by intra-arterial injection during the years 1933 to 1955. While their subsequent mortality experience reflected the diseases, mainly cerebrovascular, bringing them under investigation, it was notable that there were 12 deaths from cancer (including four primary liver tumours) among the 109 who survived more than one year after Thoro-trast administration. Between 1935 and 1941 27 patients received Thorotrast by direct injection into the ventricular system or subarachnoid space. Seventeen of these patients died within five years as a direct result of the disease bringing them under investigation. Seven of the 10 five-year survivors subsequently developed progressive cauda equina lesions, six of which have proved fatal. © 1968, British Medical Journal Publishing Group. All rights reserved.