Peripheral nerve injuries in the pediatric population: a review of the literature. Part III: peripheral nerve tumors in children

Neuritis ossificans mimicking a malignancy in a child: case report and literature review

We present the case of a child with neuritis ossificans after acute trauma, treated conservatively. The aim of the review is to compare several parameters in this disease. Emphasis is placed on the clinical-radiological features distinguishing neuritis ossificans from malignancy to avoid unnecessary biopsy and surgery.A literature review was performed. Only 18 cases were described. Except for one, all describe adults, and none had acute trauma. Nearly all were treated surgically.Our 13-year-old patient presented with posterior knee pain after trauma. MRI demonstrated a mass within the tibial nerve with oedema, some lymph nodes and increased avidity on 18fluoro-2-deoxyglucose-positron emission tomography. These findings can be reactive but also associated with malignancy. However, eggshell-like calcifications in the periphery of the mass were seen on CT. Biopsy and resection were proposed. Follow-up visits over the next weeks showed remarkable clinical improvement. Wait-and-scan was advised after international discussion. Follow-up imaging after 2 months showed resolution of the oedema and volume reduction of the mass, suggesting a benign pathology. Diagnosis of neuritis ossificans was proposed based on the clinical and radiological features. There was a favorable course with no complaints after two months. Imaging after seven months showed an almost complete regression.Neuritis ossificans should be considered within a painfull (mono)neuropathy. The initial inflammatory phase may mimic malignancy, misleading clinicians toward biopsy or surgery with the risk of nerve damage. As seen in our case, neuritis ossificans can be a self-limiting process. Therefore, conservative therapy should be considered with a wait-and-scan approach.

Diffuse neurofibroma with hypertrichosis in a toddler

Diffuse neurofibroma is a rare type of neurofibroma uncommonly reported in infancy. It is a slow growing tumor originating in the peripheral nerve sheath. We present the case of a 17-month-old boy with diffuse neurofibroma of the scalp associated with hypertrichosis. His genetic and clinical workup for neurofibromatosis was negative.

Brachial plexus peripheral nerve sheath tumors (PNSTs): clinical and surgical management in the pediatric population

PURPOSE

Peripheral nerve sheath tumors (PNSTs) are rare in pediatric patients, especially in the brachial plexus. Research on PNSTs is lacking. This article presents a retrospective cohort study of pediatric patients diagnosed and treated with PNSTs, specifically brachial plexus tumors.

METHODS

All pediatric patients intervened in a single center between 2007 and 2023 with brachial plexus tumors were systemically analyzed.

RESULTS

Eleven pediatric patients with 14 brachial plexus PNSTs were studied. The gender distribution was 64% female and 36% male, with an average age of 10.7 years. Ninety-one percent had a previous NF-1 diagnosis. Right brachial plexus presented a higher prevalence (64%). Pain, Tinel's sign, and stiffness masses were common during diagnosis. Motor deficits were noted in 43% of the patients. Surgery was indicated for symptoms, particularly pain and rapid growth, increasing malignancy risk. Due to suspected malignancy, an en bloc resection with safety margins was performed. Among the patients, 57% received a histopathological diagnosis of MPNST (malignant peripheral nerve sheath tumor). Treatment included radiotherapy and chemotherapy. Clinical follow-up was conducted for all cases, involving clinical and oncological evaluations for all MPNSTs.

CONCLUSIONS

This article present a series of pediatric brachial plexus tumors, especially in NF-1, and emphasizes the importance of thorough evaluation for this group. Swift diagnosis is crucial in pediatrics, enabling successful surgery for small lesions with limited neurological symptoms, improving long-term outcomes. Prompt referral to specialized services is urged for suspected masses, irrespective of neurological symptoms. Benign tumor postsurgical progression shows better outcomes than MPNSTs, with complete resection as the primary goal. Needle-guided biopsy is not recommended.

Hypoxic culture of umbilical cord mesenchymal stem cell-derived sEVs prompts peripheral nerve injury repair

Introduction

Repair and regeneration of the peripheral nerve are important for the treatment of peripheral nerve injury (PNI) caused by mechanical tears, external compression injuries and traction injuries. Pharmacological treatment can promote the proliferation of fibroblasts and Schwann cells (SCs), which longitudinally fill the endoneurial canal and form Bungner’s band, helping the repair of peripheral nerves. Therefore, the development of new drugs for the treatment of PNI has become a top priority in recent years.

Methods

Here, we report that small extracellular vesicles (sEVs) produced from umbilical cord mesenchymal stem cells (MSC-sEVs) cultured under hypoxia promote repair and regeneration of the peripheral nerve in PNI and may be a new therapeutic drug candidate.

Results

The results showed that the amount of secreted sEVs was significantly increased in UC-MSCs compared with control cells after 48 h of culture at 3% oxygen partial pressure in a serum-free culture system. The identified MSC-sEVs could be taken up by SCs in vitro, promoting the growth and migration of SCs. In a spared nerve injury (SNI) mouse model, MSC-sEVs accelerated the recruitment of SCs at the site of PNI and promoted peripheral nerve repair and regeneration. Notably, repair and regeneration in the SNI mouse model were enhanced by treatment with hypoxic cultured UC-MSC-derived sEVs.

Discussion

Therefore, we conclude that hypoxic cultured UC-MSC-derived sEVs may be a promising candidate drug for repair and regeneration in PNI.

Brachial Plexus' Schwannoma in a Child

Children's schwannoma is a rare condition, generally occurring in a sporadic way. Its aetiology is still not fully understood. We report the case of a 10-year old girl who presented a left shoulder mass, along motility reduction of the left upper limb for 24 months before presentation at our service. A biopsy resection of the mass gave the diagnosis and 6 months after surgical resection, no complication occurred.

Intrinsic peripheral nerve and root tumor and pseudotumoral lesions at a tertiary care pediatric hospital

PURPOSE

Tumors affecting peripheral nerves in children are rare. Accurate diagnosis ensures that management is appropriate and timely. A review of intrinsic nerve tumors was completed to differentiate common peripheral nerve lesions based on clinical characteristics and investigations.

METHODS

A retrospective review was conducted for children (< 18 years old) diagnosed with an intrinsic tumor affecting peripheral nerve(s) or roots at the Children's Hospital of Eastern Ontario (CHEO) from 2009 to 2019.

RESULTS

We report 14 children with perineurioma (N = 6), neurofibroma (N = 4), intraneural ganglion cyst (N = 2), or lipomatosis (N = 2). Mean age of symptom onset was 8.2 years (range 0.3 to 17.3 years). Presenting symptoms included muscle weakness (7/14), painless muscle wasting (2/14), contracture (1/14), pain (1/14), or the identification of a painless mass (3/14). Nerve conduction studies (NCS) or electromyography (EMG) were performed in 11/14 patients. MRI was useful at differentiating between these pediatric nerve tumors. Biopsies were performed in nine patients with additional surgical management pursued in four patients.

CONCLUSION

The rare nature of peripheral nerve tumors in children can pose diagnostic challenges. NCS/EMG are important to assist with localization, and MRI is useful to distinguish more benign tumors. Key MRI, clinical, and NCS features can in some cases guide management, potentially avoiding the need for invasive procedures.