Distinction between neo plastic and radiation‐induced brachial plexopathy, with emphasis on the role of EMG

Abstract

The results of clinical, radiologic, and electrophysiologic studies are retrospectively reviewed for 55 patients with neoplastic and 35 patients with radiation-induced brachial plexopathy. The presence or absence of pain as the presenting symptom, temporal profile of the illness, presence of a discrete mass on CT of the plexus, and presence of myokymic discharges on EMG contributed significantly to the prediction of the underlying cause of the brachial plexopathy. The distribution of weakness and the results of nerve conduction studies were of no help in distinguishing neoplastic from radiation-induced brachial plexopathy.

High-Resolution 3T MR Neurography of the Brachial Plexus and Its Branches, with Emphasis on 3D Imaging

“…MRN shows a focal or diffuse enhancing mass lesion in case of tumor recurrence, with asymmetric enlargement of the plexus (Fig 17). 12,27 In postradiation patients, the abnormality is generally geographic in the radiation field and diffuse and symmetric without focal masslike enhancement on contrast examinations. Postradiation fibrosis may also be seen as T1 and T2 hypointense fat stranding with distortion and kinking of the nerve segments (Fig 16).…”

Lymphoma and peripheral neuropathy: A clinical review

“…72 However, Harper and colleagues did not find evidence for preferential involvement of the lower plexus in their series. 51 In lymphoma, the proximal plexus is often affected just distal to the root entry zone, with frequent spread to the meninges as evidenced by meningeal enhancement, epidural masses on MRI 100 or myelography, and abnormal cerebrospinal fluid cytology. 59,72 In localized lymphoma, MRI may show adenopathy or a high T2 signal mass that may enhance with contrast.…”

“…11,122 With NL, there is thickening of the nerve trunks and cords due to diffuse infiltration with increased T2 signal and some enhancement but no mass. 51,122 This picture can be mistaken for trauma or inflammatory plexopathy. 122 In general, radiation plexopathy is much less painful than malignant plexopathy.…”

“…There is typically a latency of 6 months or more from the time of radiation, and affected patients usually have experienced higher doses of radiation. 30,51,71,125 Initial symptoms are usually dysesthesias and paresthesias, and progression is slow over months to years with eventual development of weakness and reflex loss. Kori and colleagues 71,72 found that the upper plexus is more likely to be involved in radiation damage, presumably due to less protection from overlying tissue, although this was not the experience of Harper and colleagues.…”

Bilateral Diaphragmatic Paralysis after Mediastinal Radiotherapy

“…Diaphragmatic dysfunction occurring 7 months after RT discontinuation and without any other etiologic factors suggests phrenic actinic damage. Neurotoxicity after radiotherapy is widely documented [16,17]. It is fre quent in the brachial plexus associated with breast or lung cancer RT [18,19].…”