Diagnosis and treatment of lumbosacral plexopathies in patients with cancer.

Eleven patients were diagnosed as having lumbosacral plexopathy at M. D. Anderson Hospital, Houston, from August 1981 through July 1982. Four causes were documented: plexopathy secondary to metastatic disease (six cases); radiation-induced plexopathy (two cases); plexopathy secondary to intra-arterial chemotherapy (two cases); and plexopathy as the result of a second primary tumor (one case). Patients with plexopathies secondary to tumor or irradiation complained of pain in the ipsilateral lower extremity. Computed tomography of the pelvis was the most accurate method of documenting tumor in the region of the lumbosacral plexus. Radiation therapy records of patients with cervical carcinoma were reviewed with respect to positioning of intracavitary radium, which was thought to be responsible for the development of radiation-induced plexopathies. Radiation therapy and/or systemic chemotherapy provided relief of pain and improvement of neurologic deficits in three patients with metastatic involvement.