[Schwannoma of the brachial plexus resembling a breast adenocarcinoma metastasis]. / Neurinoma del plexo braquial simulando metastasis de adenocarcinoma de mama.

Schwanomas originating from the brachial plexus, although rare, may be mistaken for another type of tumour. A 40 year-old woman, who had been treated years earlier for a breast adenocarcinoma, showed in the 5-year follow-up magnetic resonance examination a localized lesion in the right brachial plexus. The presumptive radiological diagnosis was a metastasis from the primary adenocarcinoma. Following surgical access via the right axilla, a well-circumscribed mass in the brachial plexus was detected. Under intraoperative electrophysiological guidance, the lesion was observed to depend on the ulnar nerve and its complete resection was possible without compromising nerve function. Histological findings indicated a schwannoma thus ruling out the presence of metastasis. The postoperative development was uneventful and six years after surgery, the patient is to date tumour-free. To the best of our knowledge, this is the first report of a brachial plexus schwannoma arising from the ulnar branch. Intraoperative electrophysiological monitoring is essential for a good surgical outcome.

Neurinoma del plexo braquial simulando metastasis de adenocarcinoma de mama / Schwannoma of the brachial plexus resembling a breast adenocarcinoma metastasis

Los neurinomas del plexo braquial son tumores infrecuentes que pueden confundirse con otras lesiones de índole tumoral. Se presenta el caso de una mujer de 40 años, tratada previamente de un adenocarcinoma de mama derecha en el pasado, que en el estudio de extensión realizado 5 años después se detectó una lesión localizada en el plexo braquial derecho. La paciente se encontraba asintomática. El diagnóstico radiológico de presunción fue metástasis de adenocarcinoma mamario. Se realizó un abordaje axilar derecho descubriendo una lesión bien delimitada en el plexo braquial. Con ayuda de la monitorización neurofisiológica intraoperatoria, se observó que la lesión dependía de la rama cubital y se pudo realizar una resección completa preservando la función de dicho nervio. El estudio anatomopatológico confirmó que se trataba de un neurinoma, descartando así la existencia de metástasis. La evolución postoperatoria fue satisfactoria. Seis años después de la intervención no existe recidiva tumoral. En nuestro conocimiento este es el primer caso publicado en la literatura de un neurinoma del plexo braquial dependiente de la rama cubital. La monitorización neurofisiológica intraoperatoria resulta fundamental para abordar este tipo de lesiones con baja morbilidad.

Schwa nomas originating from the brachial plexus, although rare, may be mistaken for another type of tumour. A 40 year-old woman, who had been treated years earlier for a breast adenocarcinoma, showed in the 5-year follow-up magnetic resonance examination a localized lesion in the right brachial plexus. The presumptive radiological diagnosis was a metastasis from the primary adenocarcinoma. Following surgical access via the right axilla, a well-circumscribed mass in the brachial plexus was detected. Under intraoperative electrophysiological guidance, the lesion was observed to depend on the ulnar nerve and its complete resection was possible without compromising nerve function. Histological findings indicated a schwannoma thus ruling out the presence of metastasis. The postoperative development was uneventful and six years after surgery, the patient is to date tumour-free. To the best of our knowledge, this is the first report of a brachial plexus schwannoma arising from the ulnar branch. Intraoperative electrophysiological monitoring is essential for a good surgical outcome.