Rapidly progressive diffuse leptomeningeal glioneuronal tumor in an adult female: illustrative case

Abstract

BACKGROUND Diffuse leptomeningeal glioneuronal tumor (DLGNT) is a rare brain tumor only recently classified by the World Health Organization in 2016 and has few reports on its incidence in adults. OBSERVATIONS The authors describe a case of DLGNT presenting in a 47-year-old female with seizures, cranial neuropathies, and communicating hydrocephalus with rapid clinical progression. Workup demonstrated progressive leptomeningeal enhancement of the skull base, cranial nerves, and spine, and communicating hydrocephalus. Elevated serum rheumatological markers and early response to systemic corticosteroids and immunosuppressant therapy complicated the diagnosis. Multiple biopsy attempts were required to obtain diagnostic tissue. Pathology demonstrated hypercellularity surrounding leptomeningeal vessels with nuclear atypia, staining positive for GFAP, Olig2, S100, and synaptophysin. Molecular pathology demonstrated loss of chromosome 1p, BRAF overexpression but no rearrangement, and H3K27 mutation. Repeat cerebrospinal fluid (CSF) diversion procedures were required for hydrocephalus management due to high CSF protein content. LESSONS This report describes a rare, aggressive, adult presentation of DLGNT. Leptomeningeal enhancement and communicating hydrocephalus should raise suspicion for this disease process. Biopsy at early stages of disease progression is essential for early diagnosis and prompt treatment. Further study into the variable clinical presentation, histological and molecular pathology, and optimal means of diagnosis and management is needed.

Diffuse Leptomeningeal Glioneuronal Tumour: An Intriguing Case Report of an Adult Patient with a Previous Optic Astrocytoma

“…Children represent the majority of cases with DLGT [3,4,12,14], however, the patient in this case report was 26 years old at the onset of the disease. The diagnosis of DLGT is often challenging, since patients present with non-specific symptoms of raised intracranial pressure with CSF analysis negative for tumour cells [14], which was also present in our instance In cases of DGLT, a high protein concentration in the CSF can be found, which is consistent with diffuse pial glial neuronal tumours and is due to tumour cells infiltration of the meninges, chemical stimulation of tumour metabolites, destruction of the bloodbrain barrier and increased vascular permeability [11]. Biopsy, histological analysis, and molecular genetic testing are crucial for diagnosing DLGT, as imaging findings are not specific enough and cases of DLGT have been misdiagnosed as tuberculosis [14,15].…”

“…The main aim of the therapy, at the present moment, is not a total resection of the tumour, as that is not feasible, but rather a reduction and when required, insertion of a ventriculoperitoneal shunt, if hydrocephalus occurs [12], as was present in this case. At present, no standardised treatment protocol has been developed for patients with DLGT, the majority are treated with a combination of surgery, chemotherapy and radiotherapy [14], however, targeted therapy and immunotherapy are also an option [11]. The majority of patients, who are treated with chemotherapy (systemic or intrathecal), receive a combination of temozolomide, carboplatin and vincristine [16]; the patient in our case report was administered carboplatin and vincristine systemically.…”

“…Patients with a poor prognosis are often older at the time of diagnosis and have multiple site lesions and hydrocephalus, whereas those with a stable disease have a higher rate of 1p/19q codeletion [5]. Currently, no therapeutic guidelines exist, patients are treated by use of various chemotherapy regimens with or without radiation therapy and biological agents, namely carboplatin, bevacizumab, and temozolomide [9,11]. Craniospinal radiation has been proven to improve clinical outcomes and slow disease progression [11].…”

“…Currently, no therapeutic guidelines exist, patients are treated by use of various chemotherapy regimens with or without radiation therapy and biological agents, namely carboplatin, bevacizumab, and temozolomide [9,11]. Craniospinal radiation has been proven to improve clinical outcomes and slow disease progression [11]. In August 2021, a 26-year-old man presented with progressive headaches to the neurosurgical outpatient clinic at the University Medical Centre in Maribor.…”

Aggressive Diffuse Leptomeningeal Glioneuronal Tumor in a Pediatric Patient Presenting With Mismatch Repair Gene Mutations

“…Radiological imaging can demonstrate leptomeningeal enhancement, discrete intramedullary spinal masses, communicating hydrocephalus, or combinations of these findings [ 5 ]. DLGNT can be misdiagnosed for infectious or inflammatory pathologies [ 8 ]. Communicating hydrocephalus is the most frequently reported clinical finding and may be a direct result of leptomeningeal membrane thickening, altered CSF circulation, and impaired reabsorption [ 9 ].…”