Substantial relief of discomfort may be anticipated by most patients suffering from pelvic and lower-extremity pain who are treated by arterial infusion of nitrogen mustard. Seventy-three patients with intractable pain secondary to malignancy arising in the pelvis received 83 percutaneous pelvic arterial infusions of this drug. Sixty infusions (72%) resulted in marked relief from pain for periods averaging 6-8 weeks. Advantages of the procedure are low toxicity, relative simplicity and availability of technique, and an acceptable rate of complications with minimal morbidity. Patients experiencing satisfactory results may expect significant relief from a second infusion for recurrent pain. The most rewarding result is the freedom from the cyclic return of pain characterized by oral and intramuscular analgesic therapy. Little or no relief can be expected in patients with pain caused by compression fractures of the vertebrae, or where the tumor burden is so great that adequate perfusion of the involved nerves is not possible. One should consider this procedure for controlling pain before resorting to the more dangerous and potentially disabling techniques of spinal cordotomy or intrathecal alcohol injection. References Bateman JR, Hazen JG, Stolinsky DC, Steinfeld JL (1966) Advanced carcinoma of the cervix treated by intra-arterial methotrexate. Am J Obstet Gynecol 96: 181-187 Calabresi P, Parks RW Jr (1970) Alkylating agents, antimetabolites, hormones. and other antiproliferative agents. In: Goodman LS, Gilman A (eds) The pharmacological basis of therapeutics, 4th edn.