Metastatic brachial plexopathy presenting as radiation-induced plexopathy in metastatic lung cancer: a case report and literature review

Metastatic brachial plexopathy (MBP) is a rare but debilitating complication of advanced malignancies, most commonly associated with lung and breast carcinomas. Distinguishing MBP from radiation-induced brachial plexopathy (RIBP) represents a significant clinical challenge due to their overlapping clinical presentations and similar appearances on structural imaging. While magnetic resonance imaging (MRI) is considered the gold standard for evaluating the brachial plexus (BP), it often lacks the sensitivity required to definitively differentiate between malignant infiltration and post-radiation fibrosis.