Neuromuscular disorders in systemic malignancy.

Paraneoplastic neuronopathies are presumed to be the result of an autoimmune attack directed at neuronal proteins, and both humoral and cell-mediated mechanisms have been postulated. The lower motor neuron syndrome after irradiation to the spinal column is caused by a proximal motor polyradiculopathy. Prevention of brachial plexopathy after radiotherapy for breast cancer may be accomplished by lower doses and surgical management of the axilla. Polymerase chain reaction casts doubt on the distinction between neoplastic and paraneoplastic mechanisms of neuromuscular manifestations of lymphoproliferative diseases. Shared antigenic components may underlie the association between inflammatory neuropathy and malignant melanoma. Advances in chemotherapy strategies against responsive tumors are hindered by the toxic effects of agents on peripheral nerves.