Progression of atypical extraventricular neurocytoma to anaplastic ganglioglioma

Update on genomic and molecular landscapes of well-differentiated liposarcoma and dedifferentiated liposarcoma

Well-differentiated liposarcoma (WDLPS) is the most frequent subtype of liposarcoma and may transform into dedifferentiated liposarcoma (DDLPS) which is a more aggressive subtype. Retroperitoneal lesions of WDLPS/DDLPS tend to recur repeatedly due to incomplete resections, and adjuvant chemotherapy and radiotherapy have little effect on patient survival. Consequently, identifying therapeutic targets and developing targeted drugs is critical for improving the outcome of WDLPS/DDLPS patients. In this review, we summarised the mutational landscape of WDLPS/DDLPS from recent studies focusing on potential oncogenic drivers and the development of molecular targeted drugs for DDLPS. Due to the limited number of studies on the molecular networks driving WDLPS to DDLPS development, we looked at other dedifferentiation-related tumours to identify potential parallel mechanisms that could be involved in the dedifferentiation process generating DDLPS.

A rare diagnosis of an extraventricular neurocytoma

Background:

Extraventricular neurocytoma (EVN) is an extremely rare neoplasm of the central nervous system. As reported, it arises in a variety of locations, but mainly within the cerebral hemispheres. Despite its histological similarity with central neurocytoma (CN), EVN occurs outside the ventricular system and, in 2007, was recognized by the World Health Organization as a separate entity.

Case Description:

A 39-year-old man, with a ventriculoperitoneal shunt inserted for communicating hydrocephalus, was admitted at our Unit of Neurosurgery with a 1-month history of gait disturbance, postural instability, speech disorders, and occasional incontinence. Computed tomography scan and magnetic resonance imaging showed a mixed-density neoplasm in the left frontotemporal area, with anterior cerebral falx shift, and perilesional edema. The patient underwent surgical procedure; microsurgical excision of the lesion was performed through left pterional approach. Histopathological and immunohistochemical examination revealed monomorphic round cells of the neuronal lineage, with a percentage of Ki-67 positive nuclei <5% and no evidence of mitosis or necrotic areas. According to radiologic features, this pattern was compatible with the diagnosis of EVN. Patient had a favorable recovery and he is still in follow-up.

Conclusion:

Because of their rarity, clinical, radiologic, and histopathological characteristics of EVNs are not yet well defined, as well as the optimal therapeutic management. Whereas EVNs are rarely described in literature, we aimed to share and discuss our experience along with a review of the published literature.

Primary Anaplastic Ganglioglioma of the Temporal Lobe With Brainstem Involvement: A Case Report and Literature Review

Anaplastic ganglioglioma (AGG) is a rare and aggressive counterpart of the more benign and frequently encountered glioma. Herein, we present a 21-year-old female who presented with episodes of total amnesia and complex partial seizures, which led to the diagnosis of AGG localized to the medial temporal lobe. She subsequently underwent surgical cytoreduction of the tumor three times with adjuvant chemoradiotherapy. The extent of resection throughout the surgeries was hindered by the extension of the tumor to critical neurovascular structures; during the last surgery, invasion into the pons was noted, which posed a significant clinical challenge.

Extraventricular neurocytoma with ganglioid differentiation of the sellar and parasellar regions in an elderly patient: A case report

Background:

Extraventricular neurocytoma (EVN) is a rare variant of central neurocytoma which arises outside of the ventricular system. Diffuse ganglioid differentiation is a characteristic seen in a subset of these tumors which has an uncertain prognostic significance. Typically, EVN presents in children and young adults. Given the rarity of this tumor, the natural history and response to treatments remain unclear.

Case Description:

We present a case of EVN with diffuse ganglioid differentiation in a 70-year-old male which arose in the midline parasellar region and extended into the third ventricle. This is the oldest such patient reported. Despite prior reports that extremes of age are associated with more aggressive behavior, the tumor in this case did not exhibit such an aggressive course.

Conclusion:

In this report, we review the natural history and clinical course of this patient and summarize the literature regarding this rare pathological entity. Our patient responded well to therapy despite older age, ganglioid differentiation, and higher mitotic index.

Impact of surgery, adjuvant treatment, and other prognostic factors in the management of anaplastic ganglioglioma

BACKGROUND/PURPOSE

Anaplastic ganglioglioma (AGG) is a rare tumor with both glial and neuronal component accounting for less than 1% of all CNS tumors with limited information about the optimum treatment and outcome of these tumors.

METHOD AND MATERIALS

We did a thorough search of the PubMed with the following MesH terms: "Ganglioglioma; Anaplastic ganglioglioma; Ganglioglioma AND treatment; and Anaplastic ganglioglioma AND survival" to find all possible publications related to AGG to perform an individual patient data analysis and derive the survival outcome and optimum treatment of these tumors.

RESULTS

A total of 56 articles were retrieved pertaining to AGG with 88 patients. However, a total of 40 publications found eligible with 69 patients for individual patient data analysis. Median age for the entire cohort was 16 years (range 0.2-77 years). Surgical details were available for 64 patients. A gross total or near total resection was reported in 21 cases (32.8%), subtotal resection or debulking was reported in 25 cases (39.1%). Surgical details were available for 64 patients. A gross total or near total resection was reported in 21 cases (32.8%), and subtotal resection or debulking was reported in 25 cases (39.1%). Median overall survival (OS) was 29 months [95% CI 15.8-42.2 months] with 2- and 5-year OS 61 and 39.4% respectively.

CONCLUSION

AGG is associated with a dismal. Pediatric age and a gross total resection of tumor confer a better progression-free survival and OS. Hence, surgery should remain the cornerstone of therapy. However, because of modest survival, there is enough opportunity to improve survival with addition of adjuvant radiation and chemotherapy. A whole genome sequencing and molecular characterization would help to derive the best treatment option.

Importance of immune monitoring approaches and the use of immune checkpoints for the treatment of diffuse intrinsic pontine glioma: From bench to clinic and vice versa (Review)

On the basis of immunological results, it is not in doubt that the immune system is able to recognize and eliminate transformed cells. A plethora of studies have investigated the immune system of patients with cancer and how it is prone to immunosuppression, due in part to the decrease in lymphocyte proliferation and cytotoxic activity. The series of experiments published following the demonstration by Dr Allison's group of the potential effect of anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) paved the way for a new perception in cancer immunotherapy: Immune checkpoints. Several T cell-co-stimulatory molecules including cluster of differentiation (CD)28, inducible T cell co-stimulatory, 4-1BB, OX40, glucocorticoid-induced tumor necrosis factor receptor-related gene and CD27, and inhibitory molecules including T cell immunoglobulin and mucin domain-containing-3, programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), V-domain immunoglobulin suppressor of T cells activation, T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain, and B and T lymphocyte attenuator have been described in regulating T cell functions, and have been demonstrated to be essential targets in immunotherapy. In preclinical studies, glioblastoma multiforme, a high-grade glioma, the monotherapy targeting PD-1/PD-L1 and CTLA-4 resulted in increased survival times. An improved understanding of the pharmacodynamics and immune monitoring on glioma cancers, particularly in diffuse intrinsic pontine glioma (DIPG), an orphan type of cancer, is expected to have a major contribution to the development of novel therapeutic approaches. On the basis of the recent preclinical and clinical studies of glioma, but not of DIPG, the present review makes a claim for the importance of investigating the tumor microenvironment, the immune response and the use of immune checkpoints (agonists or antagonists) in preclinical/clinical DIPG samples by immune monitoring approaches and high-dimensional analysis. Evaluating the potential predictive and correlative biomarkers in preclinical and clinical studies may assist in answering certain crucial questions that may be useful to improve the clinical response in patients with DIPG.