Glioneuronal tumor with neuropil-like islands of the spinal cord with diffuse leptomeningeal neuraxis dissemination

Understanding diffuse leptomeningeal glioneuronal tumors

INTODUCTION

Diffuse leptomeningeal glioneuronal tumors (DLGNTs) pose a rare and challenging entity within pediatric central nervous system neoplasms. Despite their rarity, DLGNTs exhibit complex clinical presentations and unique molecular characteristics, necessitating a deeper understanding of their diagnostic and therapeutic nuances.

METHODS

This review synthesizes contemporary literature on DLGNT, encompassing epidemiology, clinical manifestations, pathological features, treatment strategies, prognostic markers, and future research directions. To compile the existing body of knowledge on DLGNT, a comprehensive search of relevant databases was conducted.

RESULTS

DLGNT primarily affects pediatric populations but can manifest across all age groups. Its diagnosis is confounded by nonspecific clinical presentations and overlapping radiological features with other CNS neoplasms. Magnetic resonance imaging (MRI) serves as a cornerstone for DLGNT diagnosis, revealing characteristic leptomeningeal enhancement and intraparenchymal involvement. Histologically, DLGNT presents with low to moderate cellularity and exhibits molecular alterations in the MAPK/ERK signalling pathway. Optimal management of DLGNT necessitates a multidisciplinary approach encompassing surgical resection, chemotherapy, radiotherapy, and emerging targeted therapies directed against specific genetic alterations. Prognostication remains challenging, with factors such as age at diagnosis, histological subtypes, and genetic alterations influencing disease progression and treatment response. Long-term survival data are limited, underscoring the need for collaborative research efforts.

CONCLUSION

Advancements in molecular profiling, targeted therapies, and international collaborations hold promise for improving DLGNT outcomes. Harnessing the collective expertise of clinicians, researchers, and patient advocates, can advance the field of DLGNT research and optimize patient care paradigms.

Malignant transformation of adult-onset pilocytic astrocytoma to diffuse leptomeningeal glioneuronal tumor within the thoracic spine: a case report and review of the literature

We describe a 31-year-old male who presented with progressive myelopathy from a thoracic pilocytic astrocytoma (PA). Following multiple recurrences and resections, 10 years after his index surgery, pathology revealed diffuse leptomeningeal glioneuronal tumor (DLGNT) with high-grade features. We discuss his clinical course, management, histopathological findings, and present a comprehensive review of spinal PA undergoing malignant transformation in adults and adult-onset spinal DLGNT. To our knowledge, we present the first reported case of adult-onset spinal PA malignant transformation to DLGNT. Our case adds to the paucity of clinical data characterizing such transformations and highlights the importance of developing novel management paradigms.

Tomotherapy for Cranio-Spinal Irradiation

•

Tomotherapy is safe and effective for cranio-spinal irradiation, both in paediatric patients and in adults, with similar disease-specific outcomes and toxicities as other techniques such as 3DCRT or IMRT/VMAT.

•

Tomotherapy offers several technical advantages when compared to other radiotherapy techniques such as higher target conformity and better dose homogeneity.

•

Helical Tomotherapy provides good organ-at-risk sparing for several structures, especially the vertebrae, parotids, and optic system.

•

Reported treatment time/ beam-on-time is longer with helical Tomotherapy compared to other techniques.

Tomotherapy is a method of delivering rotational IMRT offering various advantages, notably for complex and large targets such as the cranio-spinal axis. This systematic literature review reports on main clinical outcomes and toxicities in patients with various cancer types that received whole craniospinal axis irradiation (CSI) using Tomotherapy and offers a comprehensive comparison between Tomotherapy and other radiotherapy delivery techniques. Databases including PubMed, PubMed Central, Embase, and Cochrane were searched using the keywords “tomotherapy” AND “craniospinal”. Fifty-six papers were included in the review. Patient population was adult in 9 papers, paediatric in 26 papers and mixed in 14 papers. Patients treated with helical Tomotherapy had similar disease-specific clinical outcomes and toxicities as patients treated using other techniques. Compared to any other technique, Tomotherapy provides better target coverage, homogeneity, and conformity in 23, 34 and 22 reports. Tomotherapy showed better organ-at-risk sparing for the thyroid, parotids, cochlea, eyes, heart and esophagus. Beam-On-Time (BOT) was reported to be longer for Tomotherapy in most studies (Median BOT: HT = 11 min, VMAT = 5.49 min, 3DCRT = 1.46 min). In conclusion, Tomotherapy offers good cranio-spinal axis coverage with improved homogeneity and conformity compared to other techniques, but with a considerably longer treatment time. Clinical outcome and toxicities suggest using Tomotherapy for CSI is efficient and safe.

Atypical and aggressive diffuse leptomeningeal glioneuronal tumor in a young adult: A case report and review of the literature

Background

DLGNT is a rare tumor, commonly diagnosed in pediatric age; in most cases, the pathology presents a slow and indolent evolution. We present a case report of a young adult affected by DLGNT characterized by aggressive and atypical behavior.

Case Description

A 21-year-old male presented with mild paraparesis and hypoesthesia with a D2 level. MRI scan of the brain and spine showed a dorsal intramedullary lesion; a diffuse craniospinal leptomeningeal thickening was also present. After a week, the neurological status deteriorated rapidly with paraparesis worsening and onset of acute hydrocephalus. The patient underwent external ventricular drain positioning; a C7-D4 laminectomy was subsequently performed with partial tumor resection. Histological examination revealed a DLGNT with aggressive aspects (Ki67 30%). Postoperatively, the patient showed an immediate mild worsening of the lower limbs deficit. After a few days, severe further neurological deterioration occurred with progressive motor deficit to the upper limbs and ultimately respiratory failure. Mechanical ventilation was necessary and the patient was transferred to the ICU; during the following weeks, he developed tetraplegia and underwent ventriculoperitoneal shunt positioning. By the time, the histological diagnosis was available, the clinical status would not allow radiotherapy or chemotherapy. The patient deceased approximately 90 days after hospitalization due to respiratory complications.

Conclusion

DLGNT is a rare tumor; diagnosis requires a high index of suspicion and confirmation with biopsy. Although most cases have an indolent course, some patients may have aggressive forms. High proliferation index, hydrocephalus occurrence, and massive craniospinal leptomeningeal spread appear to be associated with worse prognosis.

Glioneuronal tumor with neuropil-like islands in the spinal cord: A case report and literature review

RATIONALE

Glioneuronal tumor with neuropil-like islands (GTNI) is a distinctive neoplasm located in the cerebrum. Moreover, spinal GTNI is extremely rare. Herein, we present a case of spinal GTNI and review the related literature.

PATIENT CONCERNS

A 38-year-old Chinese woman presented to our hospital with a 6-month history of neck pain and a 1-month history of dizziness.

DIAGNOSES

Magnetic resonance imaging revealed a large intramedullary mass spanning the length of the spinal cord from C1 to C4. Microscopic and immunohistochemical examinations of the tumor tissue revealed findings typical of GTNI.

INTERVENTIONS

The patient underwent C1 to C4 intraspinal gross tumor resection.

OUTCOMES

Follow-up results showed that the patient had no recurrence 6 months after tumor resection.

LESSONS

GTNI in the spinal cord is a highly rare neoplasm with poor prognosis. Therefore, clinicians and pathologists should differentiate GTNI from other benign glioneuronal tumors, and long-term follow-up of patients with spinal GTNI is necessary.

Diffuse Leptomeningeal Glioneuronal Tumour with 9-Year Follow-Up: Case Report and Review of the Literature

In 2016, the World Health Organisation Classification (WHO) of Tumours was updated with diffuse leptomeningeal glioneuronal tumour (DLGNT) as a provisional unit of mixed neuronal and glial tumours. Here, we report a DLGNT that has been re-diagnosed with the updated WHO classification, with clinical features, imaging, and histopathological findings and a 9-year follow-up. A 16-year-old girl presented with headache, vomiting, and vertigo. Magnetic resonance imaging (MRI) demonstrated a hyperintense mass with heterogenous enhancement in the right cerebellopontine angle and internal auditory canal. No leptomeningeal involvement was seen. The histological examination revealed neoplastic tissue of moderate cellularity formed mostly by oligodendrocyte-like cells. Follow-up MRI scans demonstrated cystic lesions in the subarachnoid spaces in the brain with vivid leptomeningeal enhancement. Later spread of the tumour was found in the spinal canal. On demand biopsy samples were re-examined, and pathological diagnosis was identified as DLGNT. In contrast to most reported DLGNTs, the tumour described in this manuscript did not present with diffuse leptomeningeal spread, but later presented with leptomeningeal involvement in the brain and spinal cord. Our case expands the spectrum of radiological features, provides a long-term clinical and radiological follow-up, and highlights the major role of molecular genetic testing in unusual cases.

Diffuse leptomeningeal glioneuronal tumour (DLGNT) in children: the emerging role of genomic analysis

Diffuse leptomeningeal glioneuronal tumours (DLGNT) represent rare enigmatic CNS tumours of childhood. Most patients with this disease share common radiological and histopathological features but the clinical course of this disease is variable. A radiological hallmark of this disease is widespread leptomeningeal enhancement that may involve the entire neuroaxis with predilection for the posterior fossa and spine. The classic pathologic features include low- to moderate-density cellular lesions with OLIG2 expression and evidence of ‘oligodendroglioma-like’ appearance. The MAPK/ERK signaling pathway has recently been reported as a potential driver of tumourigenesis in up to 80% of DLGNT with KIAA1549:BRAF fusions being the most common event seen. Until now, limited analysis of the biological drivers of tumourigenesis has been undertaken via targeted profiling, chromosomal analysis and immunohistochemistry. Our study represents the first examples of comprehensive genomic sequencing in DLGNT and shows that it is not only feasible but crucial to our understanding of this rare disease. Moreover, we demonstrate that DLGNT may be more genomically complex than single-event MAPK/ERK signaling pathway tumours.

Diffuse leptomeningeal glioneuronal tumour: where to biopsy? Case report and literature review

PURPOSE

Diffuse leptomeningeal glioneuronal tumour (DLGT) is an infrequent entity. Diagnosis is made with biopsy but with so few cases described management, prognosis remains undefined. There are not currently any articles regarding most effective place to biopsy.

METHODS

Current literature review and introduction of the case of a 3-year-old male presenting at the emergency room with irritability, vomiting and nuchal rigidity. A head CT was made showing tetraventricular enlargement and a posterior fossa cyst.

RESULTS

Patient underwent urgent ventriculoperitoneal shunting surgery with complete symptomp resolution. Brain MRI showed diffuse leptomeningeal enhancing, predominantly in basal cisterns, and multiple cystic-solid lesions along the neural axis. After ruling other conditions, a biopsy among intraoperative samples, was obtained of a PET positive gadolinium spinal enhancing lesion at D8 level, with the final diagnosis of DLGT.

CONCLUSION

DLGT can present as acute hydrocephalus. Biopsy stablishes the diagnosis but the place to take the sample can be difficult to select. Our experience suggests that PET-CT and intraoperative biopsy analysis can improve the effectivity of a representative sample.

Pediatric midline H3K27M-mutant tumor with disseminated leptomeningeal disease and glioneuronal features: case report and literature review

BACKGROUND

H3K27M-mutant midline lesions were recently reclassified by the World Health Organization (WHO) as "diffuse midline glioma" (DMG) based entirely on their molecular signature. DMG is one of the most common and most lethal pediatric brain tumors; terminal progression is typically caused by local midbrain or brainstem progression, or secondary leptomeningeal dissemination. H3K27M mutations have also been infrequently associated with a histologically and prognostically diverse set of lesions, particularly spinal masses with early leptomeningeal spread.

CASE PRESENTATION

A 15-year-old girl after 1 week of symptoms was found to have a T2/FLAIR-hyperintense and contrast-enhancing thalamic mass accompanied by leptomeningeal enhancement along the entire neuraxis. Initial infectious workup was negative, and intracranial biopsy was inconclusive. Spinal arachnoid biopsy revealed an H3K27M-mutant lesion with glioneuronal features, classified thereafter as DMG. She received craniospinal irradiation with a boost to the thalamic lesion. Imaging 1-month post-radiation demonstrated significant treatment response with residual enhancement at the conus.

CONCLUSIONS

This case report describes the unique presentation of an H3K27M-mutant midline lesion with significant craniospinal leptomeningeal spread on admission and atypical glioneuronal histopathological markers. With such florid leptomeningeal disease, spinal dural biopsy should be considered earlier given its diagnostic yield in classifying the lesion as DMG. Consistent with similar prior reports, this lesion additionally demonstrated synaptophysin positivity-also potentially consistent with a diagnosis of diffuse leptomeningeal glioneuronal tumor (DLGNT). In atypical DMG cases, particularly with leptomeningeal spread, further consideration of clinical and histopathological context is necessary for accurate diagnosis and prognostication.

Spinal Cord Diffuse Leptomeningeal Glioneuronal Tumor Presenting without Leptomeningeal Dissemination

BACKGROUND AND IMPORTANCE

Diffuse leptomeningeal glioneuronal tumor (DLGNT) represents a provisional entity in the 2016 World Health Organization classification of tumors; it is characterized by a widespread leptomeningeal growth and oligodendroglial-like cytology. To this day, 4 pediatric patients have been reported to present with an isolated spinal cord tumor in the absence of leptomeningeal dissemination. Gross total resection (GTR) was achieved in only 1 patient. We present the clinical and technical nuances of this unique type of tumor, as well as the second reported case of GTR in a patient with DLGNT.

CLINICAL PRESENTATION

A 4-year-old boy presented to the emergency department after an episode of flaccid paralysis of bilateral lower extremities. MRI showed an intramedullary spinal cord tumor centered at T8. The patient was taken to the operative room, where a laminectomy and tumor resection were performed; cystic and solid tumor components were identified. Pathology report was consistent with DLGNT. After achieving GTR, patient is free of recurrence after a 15-month follow-up.

CONCLUSION

No standard treatment for DLGNT has been identified. Current literature report surgery and chemotherapy with variable success rates. DLGNT presenting as an isolated intramedullary tumor is an uncommon condition which progression appears to be halted when treated promptly. Identifying solid and cystic components of this tumor is crucial for achieving GTR.

Diffuse leptomeningeal glioneuronal tumor in a Chinese adult: a novel case report and review of literature

Diffuse leptomeningeal glioneuronal tumor (DLGNT) is a rare glioma tumor classified by the World Health Organization as a central nervous system tumor in 2016. DLGNT is most common in children and adolescents but is rare in adults. A 25-year-old male patient was admitted due to recurrent seizures. Head magnetic resonance imaging revealed lesions in the right temporal lobe, which were considered to be intracranial tumors with variable properties. The patient was admitted for surgical treatment. After admission, it was confirmed that seizures were associated with right temporal lobe lesions. Right temporal epileptogenic focus resection was performed by craniotomy. Immunohistochemistry revealed that tumor cells were reactive for oligodendrocyte transcription factor 2, synaptophysin, S100 proteins, and α-thalassemia mental retardation X-linked; and partially reactive for neuronal nuclei, glial fibrillary acidic protein, and nestin. The vascular wall was reactive for vimentin, CD34, CD31, and smooth muscle actin. Ki-67 was 4%. Molecular detection demonstrated 1p36 deletion, O⁶-methylguanine-DNA-methyltransferase methylation, and positive v-raf murine sarcoma viral oncogene homolog B mutation. DLGNT. The patient recovered well after surgery and received 54 Gy/27f radiotherapy without neurological dysfunction and seizures. In this study, onset age, tumor site, tumor increment coefficient, molecular detection, treatment methods, and prognosis of 54 patients were summarized from 19 studies. DLGNT patients are characterized by more singular tumor site, smaller volume, lower increment coefficient, and longer stable disease period. Patients with DLGNT may also have a longer stable condition in cases of molecular detection of 1p/19q deletion, or BRAF fusion.

Newly Identified Characteristics and Suggestions for Diagnosis and Treatment of Diffuse Leptomeningeal Glioneuronal/Neuroepithelial Tumors: A Case Report and Review of the Literature

Diffuse leptomeningeal glioneuronal tumor is unique for communicating hydrocephalus, diffuse leptomeningeal enhancement, cystic changes, absence of tumor cells in cerebral spinal fluid, and a cell population of both glial and neuronal copositivity. It has likely been misdiagnosed as mixed glioneuronal tumors, oligodendrogliomas, and neuroepithelial tumors. Children with signs of this tumor are often worked up for infection, rheumatologic disease, or disseminated primary malignancy, resulting in unnecessary testing and treatment. We describe a 14-year-old female with recurrent headaches, hydrocephalus, and diffuse leptomeningeal enhancement discovered to be neoplastic 1 year after initial presentation, owing to extensive and unrevealing infectious and immunologic workups. Biopsies revealed atypical cells with markers of both glial and neuronal cells, positivity for OLIG-2, and focal p53 positivity. Great response was seen with temozolomide and craniospinal irradiation. Additionally, we postulate additional diagnostic indicators that may aid in earlier diagnosis and treatment decisions.

An individual patient data meta-analysis on characteristics and outcome of patients with papillary glioneuronal tumor, rosette glioneuronal tumor with neuropil-like islands and rosette forming glioneuronal tumor of the fourth ventricle

Background and Purpose

In 2007, the WHO classification of brain tumors was extended by three new entities of glioneuronal tumors: papillary glioneuronal tumor (PGNT), rosette-forming glioneuronal tumor of the fourth ventricle (RGNT) and glioneuronal tumor with neuropil-like islands (GNTNI). Focusing on clinical characteristics and outcome, the authors performed a comprehensive individual patient data (IPD) meta-analysis of the cases reported in literature until December 2012.

Methods

PubMed, Embase and Web of Science were searched for peer-reviewed articles reporting on PGNT, RGNT, and GNTNI using predefined keywords.

Results

95 publications reported on 182 patients (PGNT, 71; GNTNI, 26; RGNT, 85). Median age at diagnosis was 23 years (range 4–75) for PGNT, 27 years (range 6–79) for RGNT, and 40 years (range 2–65) for GNTNI. Ninety-seven percent of PGNT and 69% of GNTNI were located in the supratentorial region, 23% of GNTNI were in the spinal cord, and 80% of RGNT were localized in the posterior fossa. Complete resection was reported in 52 PGNT (73%), 36 RGNT (42%), and 7 GNTNI (27%) patients. Eight PGNT, 3 RGNT, and 12 GNTNI patients were treated with chemo- and/or radiotherapy as the primary postoperative treatment. Follow-up data were available for 132 cases. After a median follow-up time of 1.5 years (range 0.2–25) across all patients, 1.5-year progression-free survival rates were 52±12% for GNTNI, 86±5% for PGNT, and 100% for RGNT. The 1.5-year overall-survival were 95±5%, 98±2%, and 100%, respectively.

Conclusions

The clinical understanding of the three new entities of glioneuronal tumors, PGNT, RGNT and GNTNI, is currently emerging. The present meta-analysis will hopefully contribute to a delineation of their diagnostic, therapeutic, and prognostic profiles. However, the available data do not provide a solid basis to define the optimum treatment approach. Hence, a central register should be established.

Disseminated glioneuronal tumor with neuropil-like islands of the spinal cord: a distinctive entity

BACKGROUND

Glioneuronal tumor with neuropil-like islands (GTNI) was recently added as a novel lesion in the most recent update of the World Health Organization classification of tumors of the central nervous system in 2007. Since this tumor's initial description, approximately 28 cases of GTNI have been published. In this report, we describe the ninth case of a spinal GTNI in the world literature.

METHODS

We report a case arising in a 2-year-old female patient who presented with headaches associated with intermittent vomiting due to a tetraventricular hydrocephalus.

RESULTS

After ventriculoperitoneal shunt placement, the patient presented with lower extremity motor weakness and sensory disturbance. A dorsolumbar spine magnetic resonance imaging scan revealed an intramedullary spinal neoplasm involving T12 through L2 in association with the thick linear enhancement of the spinal cord surfaces. A brain magnetic resonance imaging scan demonstrated focal leptomeningeal enhancement in the Sylvian fissures, the basal cistern, tentorium, and multiple small cystic-like lesions extending on the cerebellar surface, brainstem, and temporal lobes. The patient underwent a T11-L2 laminectomy for a gross total tumor resection. Histology revealed a World Health Organization grade II GTNI.

CONCLUSIONS

GTNI is a rare type of glioneuronal tumor that has recently been described in the literature. The outcome of this case seems to have an unfavorable clinical course despite their low-grade morphology. However, the combination of gross total resection and adjuvant chemo-radiotherapy can enhance chances for longer survival among children with spinal GTNI associated with meningeal dissemination, and a clinical follow-up of a large series will be necessary to evaluate the long-term prognosis.

Spinal cord glioneuronal tumor with neuropil-like islands with 1p/19q deletion in an adult with low-grade cerebral oligodendroglioma

Glioneuronal tumor with neuropil-like islands (GTNI) is considered a rare variant of astrocytoma, characterized by discrete aggregates of cells expressing neuronal markers that punctuate a GFAP-positive glial background. Of the 24 published GTNI cases, only two occurred in adult spinal cords; none occurred concurrent with another CNS tumor; and none of those tested exhibited the 1p/19q deletion typical of oligodendroglioma. A 48-year-old man without significant past medical history was diagnosed with a WHO grade II oligodendroglioma by stereotactic biopsy of a lesion discovered after the patient suffered a generalized tonic-clonic seizure. By FISH analysis, this tumor exhibited the 1p/19q deletion present in up to 80% of oligodendrogliomas. The patient received 14 monthly cycles of temozolomide, and his cerebral tumor had a minor response. When the patient subsequently reported progressive paresthesias of his lower extremities, an MRI revealed an enhancing, cystic tumor of the thoracic spinal cord that was diagnosed as GTNI by histological analysis. By FISH analysis, this lesion exhibited the same 1p/19q deletion present in the concurrent cerebral oligodendroglioma. This case of a spinal cord GTNI with 1p/19q deletions constitutes the third report of a spinal cord GTNI in an adult patient; the first report of a GTNI in an individual with a separate CNS neoplasm; and the first report of a GTNI with 1p/19q deletions. This case establishes a potential genetic kinship between GTNI and oligodendroglioma that warrants further investigation.

Intraventricular glioneuronal tumor with disseminated lesions at diagnosis--a case report

A 55-year-old man presented with a large tumor in his lateral ventricles. Magnetic resonance imaging revealed disseminated lesions in the third and fourth ventricles at the time of diagnosis. The patient underwent a partial removal of the tumor in the lateral ventricles. Histologically, the surgical specimens showed glioneuronal differentiation with ganglion or ganglioid cells, Rosenthal fibers, oligodendroglia-like honeycomb appearances, a spongy pattern, perivascular pseudorosettes, and many hyalinized blood vessels. Papillary structure was not observed. The neuronal component showed a moderately high labeling index of Ki-67/MIB-1. We diagnosed this tumor as atypical intraventricular glioneuronal tumor. The disseminated lesions disappeared after chemoradiation therapy with temozolomide, and the residual tumors in the lateral ventricles remained stable for 3 years after the surgery. We discuss the pathological diagnosis, therapy and clinical course with review of the literatures.