Low-grade oligodendroglioma of the pineal gland: a case report and review of the literature

Differentiation between germinoma and other pineal region tumors using diffusion-and susceptibility-weighted MRI

PURPOSE

To evaluate the effectiveness of diffusion-weighted imaging (DWI) and susceptibility-weighted imaging (SWI) for differentiation between germinoma and other pineal region tumors.

METHOD

This retrospective study consisted of 72 patients with pathologically proven pineal region tumors between January 2010 and August 2020. Tumors were classified as germinomas (40), non-germinomatous germ cell tumors (11) (NGGCT), pineal parenchymal tumors (10) (PPT), and other types of tumors (11). Visual scale score, ADC values and SWI intratumoral susceptibility signal (ITSS) score were analyzed and compared to histopathology data.

RESULTS

The mean apparent diffusion coefficient (ADCmean) and minimum apparent diffusion coefficient (ADCmin) ratio of germinoma were significantly lower than NGGCT. ADCmean or ADCmin cut-off ratio of ≤ 1.48 or ≤ 1.32 allowed for discrimination between germinoma and NGGCT with sensitivity and specificity of 100 % and 63.6 %. An ADCmin cut-off ratio of ≥ 0.93 allowed for discrimination between germinoma and PPT with sensitivity and specificity of 60 % and 80.0 %. ADCmin cut-off ratio of ≤ 1.15 allowed for discrimination of germinoma from other types of tumors with sensitivity and specificity of 87.5 % and 54.5 %.

CONCLUSIONS

ADC ratio can differentiate germinoma from other types of pineal region tumors. Our initial results suggest that ITSS score was not significantly correlated with specific histology subtype.

Benign and Malignant Tumors of the Pineal Region

Pineal region tumors fall into five broad categories: benign pineal region tumors, glial tumors, papillary tumors, pineal parenchymal tumors, and germ cell tumors. Genetic and transcriptional studies have identified key chromosomal alterations in germinomas (RUNDC3A, ASAH1, LPL) and in pineocytomas/pineoblastomas (DROSHA/DICER1, RB1). Pineal region tumors generally present with symptoms of hydrocephalus including nausea, vomiting, papilledema, and the classical Parinaud's triad of upgaze paralysis, convergence-retraction nystagmus, and light-near pupillary dissociation. Workup requires neuroimaging and tissue diagnosis via biopsy. In germinoma cases, diagnosis may be made based on serum or CSF studies for alpha-fetoprotein or beta-HCG making the preferred treatment radiosurgery, thereby preventing the need for unnecessary surgeries. Treatment generally involves three steps: CSF diversion in cases of hydrocephalus, biopsy through endoscopic or stereotactic methods, and open surgical resection. Multiple surgical approaches are possible for approach to the pineal region. The original approach to the pineal region was the interhemispheric transcallosal first described by Dandy. The most common approach is the supracerebellar infratentorial approach as it utilizes a natural anatomic corridor for access to the pineal region. The paramedian or lateral supracerebellar infratentorial approach is another improvement that uses a similar anatomic corridor but allows for preservation of midline bridging veins; this minimizes the chance for brainstem or cerebellar venous infarction. Determination of the optimal approach relies on tumor characteristics, namely location of deep venous structures to the tumor along with the lateral eccentricity of the tumor. The immediate post-operative period is important as hemorrhage or swelling can cause obstructive hydrocephalus and lead to rapid deterioration. Adjuvant therapy, whether chemotherapy or radiation, is based on tumor pathology. Improvements within pineal surgery will require improved technology for access to the pineal region along with targeted therapies that can effectively treat and prevent recurrence of malignant pineal region tumors.

Large infratentorial cystic oligodendroglioma in a pregnant patient: A case report of a rare presentation and literature review

Oligodendrogliomas (ODGs) are rare brain tumors in adults, mostly presenting as a supratentorial solid mass, while less than 10% occur infratentorially. Infratentorial cystic ODGs are extremely rare. We reported a large partially cystic cerebellar ODG in a 31‐week pregnant patient with an unusual presentation and discussed the challenging management.

Understanding Parinaud's Syndrome

Parinaud's syndrome involves dysfunction of the structures of the dorsal midbrain. We investigated the pathophysiology related to the signs and symptoms to better understand the symptoms of Parinaud's syndrome: diplopia, blurred vision, visual field defects, ptosis, squint, and ataxia, and Parinaud's main signs of upward gaze paralysis, upper eyelid retraction, convergence retraction nystagmus (CRN), and pseudo-Argyll Robertson pupils. In upward gaze palsy, three structures are disrupted: the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), interstitial nucleus of Cajal (iNC), and the posterior commissure. In CRN, there is a continuous discharge of the medial rectus muscle because of the lack of inhibition of supranuclear fibers. In Collier's sign, the posterior commissure and the iNC are mainly involved. In the vicinity of the iNC, there are two essential groups of cells, the M-group cells and central caudal nuclear (CCN) group cells, which are important for vertical gaze, and eyelid control. Overstimulation of the M group of cells and increased firing rate of the CCN group causing eyelid retraction. External compression of the posterior commissure, and pretectal area causes pseudo-Argyll Robertson pupils. Pseudo-Argyll Robertson pupils constrict to accommodation and have a slight response to light (miosis) as opposed to Argyll Robertson pupils were there is no response to a light stimulus. In Parinaud's syndrome patients conserve a slight response to light because an additional pathway to a pupillary light response that involves attention to a conscious bright/dark stimulus. Diplopia is mainly due to involvement of the trochlear nerve (IVth cranial nerve. Blurry vision is related to accommodation problems, while the visual field defects are a consequence of chronic papilledema that causes optic neuropathy. Ptosis in Parinaud's syndrome is caused by damage to the oculomotor nerve, mainly the levator palpebrae portion. We did not find a reasonable explanation for squint. Finally, ataxia is caused by compression of the superior cerebellar peduncle.

Pineal parenchymal tumor of intermediate differentiation: a systematic review and contemporary management of 389 cases reported during the last two decades

Pineal parenchymal tumor of intermediate differentiation (PPTID) is a WHO grade II and III tumor arising from pineal parenchymal cells. PPTID is a rare tumor accounting for less than 1% of all primary central nervous system neoplasms. Therefore, reports describing the clinical characteristics and biological features of PPTID are lacking. Moreover, the therapeutic strategy remains controversial. The current study aimed to evaluate treatment results and problems of contemporary therapeutic modalities of PPTID based on its features compared with other pineal parenchymal tumors. A comprehensive systematic literature review of 69 articles was performed, including articles on PPTID (389 patients) and similar tumors. Patient demographics, disease presentation, imaging characteristics, biological features, and current therapeutic options and their results were reviewed. We found that histopathological findings based on current WHO classification are well associated with survival; however, identifying and treating aggressive PPTID cases with uncommon features could be problematic. A molecular and genetic approach may help improve diagnostic accuracy. Therapeutic strategy, especially for grade III and aforementioned uncommon and aggressive tumors, remains controversial. A combination therapy involving maximum tumor resection, chemotherapy, and radiotherapy could be the first line of treatment. However, although challenging, a large prospective study would be required to identify ways to improve the clinical results of PPTID treatment.

Pineal Gland Tumor but not Pinealoma: A Case Report

The pineal gland is a small pinecone-shaped and functionally endocrine structure located in the epithalamus region. Developmentally, the pineal gland is considered as a part of the epithalamus. It plays a role in the entrainment of the circadian rhythms of an organism by producing melatonin, a functionally important hormone. Lesions of the pineal region are rare compared to other parts of the brain. A lesion may be tumorous or non-tumorous in nature. The most common lesions are tumors that are pineal parenchymal tumors (PPT) in origin. Gliomas are the second most common tumors in the pineal region. We report a case of a high-grade oligodendroglioma, not commonly seen in the pineal region, in a 45-year-old male. The patient was suspected to have a mass in the pineal region on a computed tomography (CT) scan and histology confirmed the diagnosis of oligodendroglioma. This is a unique case because only five such cases have been reported so far.

Low-Grade Oligodendroglioma of the Pineal Region: Case Report

Background Although germ cell tumors and pineal cell tumors account for most of the histologic tumor subtypes, > 17 different tumors can arise in this location. We report a rare case of a low-grade oligodendroglioma that arose in the pineal region.

Clinical Presentation A young woman complaining of a headache underwent magnetic resonance imaging that showed a mass in the pineal region and mild hydrocephalus. A ventriculoperitoneal shunt was performed followed by a near-total tumor removal, due to tumor invasion of the tectal plate and thalamus. The histologic examination confirmed the diagnosis of a low-grade oligodendroglioma. The patient then underwent chemotherapy and radiotherapy as adjuvant therapies.

Conclusion Although the pineal region is a common place for a large number of tumoral lesions, low-grade oligodendrogliomas are extremely rare in this location. This case is only the second account of a benign oligodendroglioma of the pineal region reported in the literature.

Pineal region tumors: Clinical symptoms and syndromes

The present paper investigates the clinical picture and the different clinical signs that reveal pineal region tumors or appear during the course of the follow-up. Biological malignancy and tumor extension determine the semiology and its setting up mode. Typical endocrine signs, dominated by abnormal puberty development, are frequently a part of the clinical scene. Bifocal or ectopic localization in the hypothalamic-pituitary region is accompanied by other endocrine signs such as ante- or post-pituitary insufficiencies which occur several months or even years after the first neurological signs appear. Due to a mass syndrome and obstructive hydrocephalus, intracranial hypertension signs are frequent but unspecific. A careful ophthalmologic examination is essential to search upward gaze paralysis and other signs of the Parinaud's tetrad or pentad. Midbrain dysfunction, including extrinsic aqueduct stenosis, are also prevalent. Except for abnormal pubertal signs, hyper-melatoninemia (secretory tumors) or a-hypo-melatoninemia (tumors destructing pineal) generally remains dormant. Some patients present sleep problems such as narcolepsy or sleepiness during the daytime as well as behavioral problems. This suggests a hypothalamic extension rather than a true consequence of melatonin secretion anomalies. Similarly, some patients may present signs of a "pinealectomized" syndrome, including (cluster) headaches, tiredness, eventually responsive to melatonin.

Cluster and Principal Component Analysis of Human Glioblastoma Multiforme (GBM) Tumor Proteome

BACKGROUND

Glioblastoma Multiforme (GBM) or grade IV astrocytoma is the most common and lethal adult malignant brain tumor. Several of the molecular alterations detected in gliomas may have diagnostic and/or prognostic implications. Proteomics has been widely applied in various areas of science, ranging from the deciphering of molecular pathogen nests of discuses.

METHODS

In this study proteins were extracted from the tumor and normal brain tissues and then the protein purity was evaluated by Bradford test and spectrophotometry. In this study, proteins were separated by 2-Dimensional Gel (2DG) electrophoresis method and the spots were then analyzed and compared using statistical data and specific software. Protein clustering analysis was performed on the list of proteins deemed significantly altered in glioblastoma tumors (t-test and one-way ANOVA; P< 0.05).

RESULTS

The 2D gel showed totally 876 spots. We reported, 172 spots were exhibited differently in expression level (fold > 2) for glioblastoma. On each analytical 2D gel, an average of 876 spots was observed. In this study, 188 spots exhibited up regulation of expression level, whereas the remaining 232 spots were decreased in glioblastoma tumor relative to normal tissue. Results demonstrate that functional clustering (up and down regulated) and Principal Component Analysis (PCA) has considerable merits in aiding the interpretation of proteomic data.

CONCLUSION

2D gel electrophoresis is the core of proteomics which permitted the separation of thousands of proteins. High resolution 2DE can resolve up to 5,000 proteins simultaneously. Using cluster analysis, we can also form groups of related variables, similar to what is practiced in factor analysis.

Gliomas of the pineal region

Although several series of pineal region tumors are available, the issue of pineal gliomas has been scarcely faced in the literature. Gliomas are usually included in largest series of pineal neoplasms. Therefore, whether pineal gliomas share the biological behavior of either hemispheric gliomas or other midline lesions is not yet defined. The aim of this retrospective study is to analyze long-term morbidity and mortality of these lesions. In English published literature gliomas account for about 14-22 % of all pineal region tumors. Most of these tumors are pilocytic astrocytomas, while glioblastoma multiforme is rare. We retrospectively analyzed all pineal region tumors operated on in our department in the last 28 years, and identified eight pineal astrocytomas, accounting for 14.03 % of all pineal tumors. The series includes four pilocytic astrocytomas, two grade II diffuse astrocytomas, and two anaplastic astrocytomas. A comprehensive review of the available literature data shows that the mean survival time of WHO grade II gliomas is shorter when tumor grows in the pineal region than for hemispheric locations, although the limited amount of available data prevents a rigorous statistical analysis. This difference might be due to the peculiar infiltrating behavior of pineal tumors, which often can't be satisfactorily resected from vital structures.

Pediatric brainstem oligodendroglioma

The authors present the first report of pediatric brainstem oligodendroglioma, infiltrating midbrain, and medulla oblongata. The report details clinical features, radiological findings, and surgical steps. As this entity is exceedingly uncommon, the overall epidemiology, prognosis, and long-term outcome remain far from established.