Brachial plexus neuropathy following mantle radiotherapy.

We report two cases of presumed radiation-induced brachial plexus neuropathy in patients with lymphoma who were treated with standard mantle radiotherapy to a dose of 40 Gy in 20 fractions. Radiation-induced brachial plexopathy has not previously been reported following mantle irradiation at this dose. Both patients received chemotherapy in relapse. We postulate three possible causes: enhanced radiation sensitivity; an interaction between the chemotherapy and the radiotherapy; or an increased dose in axilla owing to a smaller separation at that point.