A rare case of cellular schwannoma involving the trigeminal ganglion

Abstract

Cellular schwannomas rarely involve the cranial nerves, being more common in the spinal and peripheral nerves. A rare case of cellular schwannoma involving the gasserian ganglion, a hitherto unreported site, that extended infratentorially to present as a cerebellopontine angle tumor is reported. It is important to recognize that cellular schwannomas can histologically mimic malignant peripheral nerve sheath tumors because of their high cellularity and mitotic activity, but they are relatively benign tumors with a tendency to recur but not metastasize.

Intracranial cellular schwannomas: a clinicopathological study of 20 cases

“…8 Cellular schwannomas of the intracranial space are more rare than those developing in peripheral sites, with only rare cases reported in the literature to date, some of them as part of general cellular schwannomas series 2-7 and others, as single case reports convincingly illustrated. [9][10][11][12][13][14][15] Patients in this current series presented with intracranial tumours at a slightly younger age (mean = 38 years) compared to cellular schwannoma in general reported in the literature, ages ranging from 40 to 55 years in four studies, 2,3,5,6 with an average age of 40.9 years in another study. 4 There was a slight female predilection in our series, which is in accordance with series including tumours inside and outside the intracranial space reporting a predominance in females.…”

Cystic trigeminal schwannomas

“…On the other hand, in those tumors of V1, the temporopolar approaches are the ones of choice, while those originating in V2 and V3 infratemporal resection is preferred, allowing the exposure of the foramen ovale, the pterygopalatine ganglion and the infratemporal fossa [4,18]. For the lesions located in the Meckel cave, the pericavernosal lateral approach is preferred, with which the lesion of the trochlear and abducens nerves is diminished [4,19,20]. Finally, for pons tumors, suboccipital, retrosigmoid or latero-suboccipital approaches are used.…”

An Overview of Central Nervous System Tumours

“…CSs has a predilection for middle-aged women [172]. They are extremely rare in the CNS and involve the spinal nerves more often than the cranial nerves in the peripheral nervous system [173]. The tumour has a female predominance, a median age of 55 years, and most are located in the retroperitoneum or mediastinum [174].…”

“…CSs usually present as slow growing tumours often located deep in the paravertebral region of the mediastinum and retroperitoneum [170]. They may originate from any portion of the trigeminal nerve between the root and distal extra-cranial branches resulting in a variety of symptoms and signs, depending on the direction and extent of tumour growth [173]. CSs may be large in size, with sheets of eosinophilic cells, have bullet-shaped nuclei along with characteristic features of schwannomas i.e.…”