Hybrid neurofibroma/schwannoma of the orbit / Tumor híbrido neurofibroma/schwannoma de la órbita

Hybrid neurofibroma/schwannoma is a rare variant of hybrid peripheral nerve sheath tumours (HPNST). A Medline search up to December 2021 identified only six cases of this tumour in the orbit. We report the case of a 78-year-old man who presented with left exophthalmos. Computed tomography showed a left intraconal orbital mass. The clinico-radiological diagnosis was consistent with an intraconal cavernous angioma. Orbitotomy was performed, obtaining an 18×16×11mm mass. Two different morphologies were seen microscopically, diagnostic of hybrid neurofibroma/schwannoma. HPNSTs of the orbit are uncommon and most reported cases showed a hybrid neurofibroma/schwannoma morphology. Hybrid neurofibroma/schwannomas have been associated with neurofibromatosis and schwannomatosis. Local recurrences have been reported. The correct identification of these tumours is important due to their potential use as a syndromic marker.(AU)

El tumor híbrido neurofibroma/schwannoma es una lesión rara incluida dentro de tumores híbridos de la vaina del nervio periférico. Mediante revisión bibliográfica en Medline hasta diciembre de 2021 se identificó solo seis casos de este tumor en la órbita. Presentamos el caso de un varón de 78 años que consultó por exoftalmos izquierdo. La tomografía computarizada mostró una masa orbitaria intraconal izquierda. El diagnóstico clínico-radiológico fue compatible con angioma cavernoso intraconal. Se realizó una orbitotomía, obteniendo una masa de 18×16×11mm. Microscópicamente, el tumor mostró dos morfologías diferentes compatibles con tumor híbrido neurofibroma/schwannoma. Los tumores híbridos de la vaina del nervio periférico de la órbita son poco comunes. La mayoría de los casos informados muestran una morfología híbrida de neurofibroma/schwannoma. El tumor híbrido neurofibroma/schwannoma se ha asociado con neurofibromatosis y schwannomatosis. Se han reportado recurrencias locales. La correcta identificación de estos tumores es relevante debido a su potencial uso como marcador sindrómico.(AU)

Hybrid neurofibroma/schwannoma of the orbit.

Hybrid neurofibroma/schwannoma is a rare variant of hybrid peripheral nerve sheath tumours (HPNST). A Medline search up to December 2021 identified only six cases of this tumour in the orbit. We report the case of a 78-year-old man who presented with left exophthalmos. Computed tomography showed a left intraconal orbital mass. The clinico-radiological diagnosis was consistent with an intraconal cavernous angioma. Orbitotomy was performed, obtaining an 18×16×11mm mass. Two different morphologies were seen microscopically, diagnostic of hybrid neurofibroma/schwannoma. HPNSTs of the orbit are uncommon and most reported cases showed a hybrid neurofibroma/schwannoma morphology. Hybrid neurofibroma/schwannomas have been associated with neurofibromatosis and schwannomatosis. Local recurrences have been reported. The correct identification of these tumours is important due to their potential use as a syndromic marker.