Intraneural perineurioma – a retrospective study of 19 patients

Abstract

Intraneural perineurioma is a benign neoplasm of peripheral nerve sheath with perineurial cell origin that typically affects teenagers and young adults and tends to result in a motor-predominant neuropathy. The aim of our study is to present the epidemiology, clinical presentation, way of diagnosis and management plan in a consecutive patient series. Ninteen patients diagnosed as having intraneural perineurioma were retrospectively chart reviewed. Diagnosis was done by MRI and/or biopsy with morphological, immunohistochemical staining study confirmation. Patients assessments included gender, age, symptoms, tumor localization, radiological aspect, management and pathological confirmation.Sex ratio was 10 males to 9 females with mean age of 31.2 (15-64). All the patients presented with motor deficit, ten with sensory deficit. Upper limb was involved in 11 cases (among them 4 lesions of brachial plexus), the lower limb in 8 cases. On magnetic resonance imaging, 16 patients showed a nerve enlargement whereas 5 presented with atypical fusiform tumor. Eighteen patients were operated for excision biopsy and/or palliative treatment for their motor deficit. Anatomopathological analysis confirmed the diagnosis in seventeen cases with a morphological pseudo-onion bulb shape and/or specific immunohistochemical assay. One patient had only palliative treatment without excision biopsy. Our data confirmed the equal penetration of intraneural perineurioma to both sex and affected limb. Because of the benignity of the tumor, the surgical treatment focused on optimizing the functional outcome. A prospective study with long term follow-up is required for this under-diagnosed tumor.

Nerve biopsy in acquired neuropathies

“…It may be accompanied by mild sensory loss. 55,61 Intraneural perineurioma appears equally in upper and lower limb nerves, but most often in the sciatic nerve and its branches. 55,[60][61][62] There are a few cases of intraneural perineurioma affecting multiple nerves.…”

“…55,61 Intraneural perineurioma appears equally in upper and lower limb nerves, but most often in the sciatic nerve and its branches. 55,[60][61][62] There are a few cases of intraneural perineurioma affecting multiple nerves. 58 MRI shows a fusiform nerve enlargement over a length of several centimetres, isointense on T1-weighted imaging, and hyperintense on T2-weighted imaging with homogenous contrast enhancement after intravenous gadolinium injection.…”

“…54 Fusiform nerve enlargement with preserved fascicular architecture can be seen in lipomatosis, schwannoma, neurofibroma, and intraneural perineurioma. 55 Some suggest that a classical clinical presentation with typical MRI findings and nerve conduction studies can make the diagnosis of perineurioma alone. 56,57 However, other MRI series of intraneural perineurioma have instead identified non-specific nerve enlargement.…”

“…56,57 However, other MRI series of intraneural perineurioma have instead identified non-specific nerve enlargement. 55 Since the management of inflammatory mononeuritis, hereditary neuropathies, malignant peripheral nerve tumors, and intraneural perineurioma are completely different, it is important to confirm a definite diagnosis before commencing therapy. The F I G U R E 9 Photomicrograph of A, Hematoxylin and Eosin (H&E) sections showed layers of spindle-shaped cells around a central axon (arrows).…”

Nerve conduction assessment and magnetic resonance imaging for the diagnosis of localized hypertrophic neuropathy of the sciatic nerve and the lumbo-sacral plexus

“…MRI allows to diagnose LHN, as in our 32-year-old female patient, excluding PNST or nerve compressions. Whilst both IP and LHN manifest in fact as a fusiform enlargement of the affected nerve with preserved fascicular architecture at high field MRIisointense on T1 and hyperintense on T2 weighted images -IP is featured by atrophy and fatty infiltration of the muscle involved a well as variable enhancement following intravenous gadolinium administration [3,9,15,16].…”