Spinal Arachnoid Cyst Containing Nevus Cells in a Patient with a Large Congenital Melanocytic Nevus: Case Report

Non-dysraphic extramedullary intradural spinal lipoma with neurocutaneous melanocytosis

INTRODUCTION

Intradural spinal lipomas are very rare and constitute less than 1% of all spinal tumors. Such tumors are usually associated with spinal dysraphism and occur mostly in the lumbosacral or cervical region. Intradural spinal lipomas tends to be intramedullary or subpial. Meningeal melanocytoma is further rarer cases that comprise less than 0.1% of cases. These usually occur in the fifth or fifth decade and chances of malignant transformation are high.

CASE REPORT

Here, we report an extremely rare case (first to the best of our knowledge) of a 9 years female child who presented to us with rapid progressing paraparesis. She was operated and found to have an intradural purely extramedullary spinal lipoma without spinal dysraphism. Moreover, she had melanin pigment deposits all over her meninges which is further rare. On presentation, the patient was bedridden but after surgery, the patient improved and could walk without support.

CONCLUSIONS

To the best of our knowledge, this is the first case of spinal cord lipoma in dorsal location along with melanin pigments in the meninges. We discuss the pathogenesis, presentation and management of intradural extramedullary spinal lipomas.

Neurosurgical management of patients with neurocutaneous melanosis: a systematic review

OBJECTIVE

Neurocutaneous melanocytosis (NCM), also referred to as neurocutaneous melanosis, is a rare neurocutaneous disorder characterized by excess melanocytic proliferation in the skin, leptomeninges, and cranial parenchyma. NCM most often presents in pediatric patients within the first 2 years of life and is associated with high mortality due to proliferation of melanocytes in the brain. Prognosis is poor, as patients typically die within 3 years of symptom onset. Due to the rarity of NCM, there are no specific guidelines for management. The aims of this systematic review were to investigate approaches toward diagnosis and examine modern neurosurgical management of NCM.

METHODS

A systematic review was performed using the PubMed database between April and December 2021 to identify relevant articles using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Search criteria were created and checked independently among the authors. Inclusion criteria specified unique studies and case reports of NCM patients in which relevant neurosurgical management was considered and/or applied. Exclusion criteria included studies that did not report associated neurological diagnoses and neuroimaging findings, clinical reports without novel observations, and those unavailable in the English language. All articles that met the study inclusion criteria were included and analyzed.

RESULTS

A total of 26 extracted articles met inclusion criteria and were used for quantitative analysis, yielding a cumulative of 74 patients with NCM. These included 21 case reports, 1 case series, 2 retrospective cohort studies, 1 prospective cohort study, and 1 review. The mean patient age was 16.66 years (range 0.25–67 years), and most were male (76%). Seizures were the most frequently reported symptom (55%, 41/74 cases). Neurological diagnoses associated with NCM included epilepsy (45%, 33/74 cases), hydrocephalus (24%, 18/74 cases), Dandy-Walker malformation (24%, 18/74 cases), and primary CNS melanocytic tumors (23%, 17/74 cases). The most common surgical technique was CSF shunting (43%, 24/56 operations), with tethered cord release (4%, 2/56 operations) being the least frequently performed.

CONCLUSIONS

Current management of NCM includes CSF shunting to reduce intracranial pressure, surgery, chemotherapy, radiotherapy, immunotherapy, and palliative care. Neurosurgical intervention can aid in the diagnosis of NCM through tissue biopsy and resection of lesions with surgical decompression. Further evidence is required to establish the clinical outcomes of this rare entity and to describe the diverse spectrum of intracranial and intraspinal abnormalities present.

Spectrum of central nervous system abnormalities in neurocutaneous melanocytosis

AIM

Neurocutaneous melanocytosis is a rare neurocutaneous syndrome defined by the presence of large and/or multiple congenital cutaneous nevi and melanocytic deposits in the central nervous system. We sought to define the spectrum of central nervous system abnormalities in children with neurocutaneous melanocytosis.

METHOD

We retrospectively reviewed cases of neurocutaneous melanocytosis referred to the pediatric neuro-oncology service at our center from 2003 to 2010.

RESULTS

Of 14 patients (11 males, 3 females) identified, eight were living. Median age of survivors was 31 months (range 12mo-6y 10mo) while median age of death was 81 months (19mo-28y). Of the six patients who died, all had diffuse leptomeningeal melanocytic deposits and four had leptomeningeal melanoma. All patients had neuroimaging: six had findings suggestive of diffuse leptomeningeal melanocytosis; seven had multifocal melanocytic deposits; and one patient had normal neuroimaging but focal seizures. Spinal abnormalities were common: three patients had extensive dorsal spinal arachnoid cysts and one had a benign cervical spindle cell tumor. Seven patients had epilepsy. Three patients had profound developmental delay; the other 11 patients had no or mild delay.

INTERPRETATION

Children with neurocutaneous melanocytosis exhibit a wide range of intracranial and intraspinal abnormalities and variable clinical outcomes.