CS-5 A case of anaplastic pleomorphic xanthoastrocytoma in the pineal region

Tumors in the pineal gland are rare tumors that account for about 0.3% of all brain tumors and have various histological types of tumors develop with germinoma, pineocytoma, and pineoblastoma in that order. On the other hand, pleomorphic xanthoastrocytoma (PXA) is a rare tumor of less than 0.2% and frequently occurs in supratentorial cerebral surface of children and young adults.A case was a 61-year-old man whose pineal tumor was found due to visual disturbance. MRI showed a 23 mm-sized lesion with cysts and inhomogeneous enhancement in the pineal gland. Partial calcification was observed, but there was no non-communicating hydrocephalus, and no increase in HCG-β and AFP with blood sampling. A midline suboccipital craniotomy was performed in the sitting position, a head-up surgery was performed using a 4K / 3D video microscope system (ORBEYE exoscope, Olympus) by the infratentorial supracerebellar approach (ITSCA). The bridging veins and precentral cerebellar vein were dissected to expose the posterior surface of the tumor, and internal decompression was performed. For the complication of air embolism, artificial cerebrospinal fluid was sprayed, and the bilateral internal jugular veins were compressed to confirm the inflow point. There was strong adhesion to the Rt vein of Rosenthal, and the site was removed intracapsularly. Finally, subtotal resection was performed with remaining the upper part of the tumor, a blind lesion behind the Vein of Galen. Vertical gaze palsy occurred after this operation, but it gradually improved over time. Tumor showed pathologically remarkable polymorphism, poor microvascular proliferation and necrosis, but mitotic figures 4–5 / 10HPF, MIB-1 index 10%, GFAP positive, no BRAF V600E mutation. There are few reports of PXA occurring in the pineal gland, and this case is the sixth case. It is also the first report for pineal tumors using ORBEYE through ITSCA in the sitting position.

A bi-foraminal craniometric-guided approach to endoscopic third ventriculostomy and biopsy of a pineal tumour

Background: Pineal tumors are very rarely encountered, with an incidence of <1% of intracranial lesions in adults. Life-threatening hydrocephalus due to obstruction of the third ventricle can result from the location of these tumours. Endoscopic third ventriculostomy (ETV) and tumor biopsy is a safe and feasible strategy, particularly if the tumor appears benign. This mitigates the high risks of uncontrollable venous bleeding from open and stereotactic biopsies. While typically performed using either ipsilateral single or dual bur holes, the location of the tumor may require modifications to the standard endoscopic techniques. Case Description: A 55-year-old male presented with signs of intracranial hypertension and was found to have obstructive hydrocephalus due to a pineal tumour. The tumour displayed a right-sided dominance when the pre-operative imaging was assessed, which would risk forniceal injury if biopsied via a right-sided burr hole. Craniometric measurements revealed a superior trajectory to the tumour via the left foramen of Monro. A biforaminal approach was performed, with a traditional ETV using a right coronal bur hole and biopsy via a left frontal bur hole. This minimized forniceal stretching and allowed a safe biopsy. Conclusion: The bi-foraminal approach has not been widely described in the literature but can potentially avoid morbidity with biopsy in patients with right-sided pineal tumours. We believe this technique should be considered, particularly in low-resource settings where neuroendoscopy is not commonly done, and where the use of ipsilateral single or dual-bur holes may lead to forniceal injury.

Incidence, Prognostic Factors, and Survival Trend in Pineal Gland Tumors: A Population-Based Analysis

IntroductionPineal gland tumors are exceedingly rare and account for 0.4-1.0% of brain neoplasms. Their rarity has confounded a clear understanding of the prognostic factors and standards of care for these neoplasms. In this study, we aimed to investigate the incidence, prognostic indicators, and survival trend of tumors emanating from the pineal gland.MethodsWe accessed the Surveillance, Epidemiology, End Results (SEER) Program for pineal gland tumors from 1975-2016. A multivariate Cox regression model was used to investigate the impact of clinicopathological parameters on all-cause mortality. For survival trend analysis, we employed the Kaplan Meier curve and pairwise comparisons to examine the trend.ResultsWe found 1,792 and 310,003 pineal gland and brain neoplasms during 1975-2016 resulting in an incidence of 0.6%. In the multivariate Cox proportional hazards model, older age, male gender, non-germ cell tumor, and receipt of chemotherapy were significantly associated with poor survival (p &lt; 0.001). The extent of resection and radiotherapy administration did not produce survival advantages. Our result also highlighted an increased survival of pineal gland tumors over the years.ConclusionOur study investigated the prognostic factors that influenced survival in patients with pineal gland tumors. Chemotherapy use adversely affected patient outcomes and should be considered carefully in specific circumstances to avoid its harmful effects. These findings provide important evidence to improve current standards of care for this rare group of tumors. The survival of pineal tumors has improved over time reflecting improvements in current practice.

EPID-23. THE PAKISTAN BRAIN TUMOR EPIDEMIOLOGY STUDY: PAVING THE WAY FOR A NATIONAL BRAIN TUMOR REGISTRY

INTRODUCTION In Pakistan, brain tumor epidemiology has been examined in single-centre studies or as part of general cancer registries, which are limited by catchment area, age group, or are not specific to brain tumors. The Pakistan Society of Neuro-Oncology conducted a nationwide study to assess the distribution of brain tumor distribution and associated risk factors. This unfunded study explores data from across Pakistan and serves as a potential model for LMICs to emulate. METHODS A cross-sectional study was designed to include patients diagnosed with brain tumors in major neurosurgical centers in Pakistan retrospectively from January-December 2019. Patients, both alive and deceased, with a radiological diagnosis of a brain tumor were included. Data were recorded on a comprehensive online form from 35 centers, encompassing an estimated 85% of all the brain tumor patients seeking initial treatment by a neurosurgeon from the public and private sectors. Data collection was split into three regions: Sindh and Balochistan; Punjab; and Khyber Pakhtunkhwa and Islamabad. Data collection occurred between August 2020 and January 2021. RESULTS A total of 2750 brain tumor cases were recorded of which 1897 (69%) were diagnosed in the private sector hospitals. MRIs were a more common radiological study compared to CT scans. 2666 surgeries were performed, 174 individuals underwent chemotherapy and 479 underwent radiation therapy; approximately two-thirds of the patients that require adjuvant treatment are not able to receive it. Gliomas were the most common tumor, while pineal tumors were the least common. Findings indicate a low metastasis frequency and few females seeking care. CONCLUSION The study shows that brain tumors are mostly diagnosed and operated on in the private sector; the public sector should be more engaged. The study also highlights that despite inconsistencies in hospital records for brain tumor patients, reliable information can be collected in LMIC settings.

Interhemispheric transcallosal intervenous approach to a pineal region tumor

Pineal region tumors represent a formidable challenge to the neurosurgeon. Choosing the right approach is key to optimizing the extent of resection and minimizing surgical morbidity. In this video, the authors show an interhemispheric transcallosal approach to a pineal region tumor in a 15-year-old boy. The advantage of this corridor over posterior approaches is that it provides a nice view of the tumor plane with the venous complex, especially while dissecting tumor from the anterior aspect of the internal cerebral veins on their vertical path. Thus, this approach represents a safe and effective alternative for selected pineal tumors. The video can be found here: https://stream.cadmore.media/r10.3171/2021.4.FOCVID2120.

Molecular classification of a complex structural rearrangement of the RB1 locus in an infant with sporadic, isolated, intracranial, sellar region retinoblastoma

Retinoblastoma is a childhood cancer of the retina involving germline or somatic alterations of the RB Transcriptional Corepressor 1 gene, RB1. Rare cases of sellar-suprasellar region retinoblastoma without evidence of ocular or pineal tumors have been described. A nine-month-old male presented with a sellar-suprasellar region mass. Histopathology showed an embryonal tumor with focal Flexner-Wintersteiner-like rosettes and loss of retinoblastoma protein (RB1) expression by immunohistochemistry. DNA array-based methylation profiling confidently classified the tumor as pineoblastoma group A/intracranial retinoblastoma. The patient was subsequently enrolled on an institutional translational cancer research protocol and underwent comprehensive molecular profiling, including paired tumor/normal exome and genome sequencing and RNA-sequencing of the tumor. Additionally, Pacific Biosciences (PacBio) Single Molecule Real Time (SMRT) sequencing was performed from comparator normal and disease-involved tissue to resolve complex structural variations. RNA-sequencing revealed multiple fusions clustered within 13q14.1-q21.3, including a novel in-frame fusion of RB1-SIAH3 predicted to prematurely truncate the RB1 protein. SMRT sequencing revealed a complex structural rearrangement spanning 13q14.11-q31.3, including two somatic structural variants within intron 17 of RB1. These events corresponded to the RB1-SIAH3 fusion and a novel RB1 rearrangement expected to correlate with the complete absence of RB1 protein expression. Comprehensive molecular analysis, including DNA array-based methylation profiling and sequencing-based methodologies, were critical for classification and understanding the complex mechanism of RB1 inactivation in this diagnostically challenging tumor.

Epidemiological Profiling and Trends of Primary Intracranial Tumors: A Hospital-Based Brain Tumor Registry from a Tertiary Care Center

Background and Objectives Hospital-based cancer registry is an essential tool for augmentation of the standard of care, administration motive, and resource for population-based cancer registries. Here, we presented hospital-based brain tumor registry (HBBTR) to outline a comprehensive epidemiological data, both clinical and histopathological, as well as trends of central nervous system tumors. In addition, we compare this data with national brain tumor data as well as an international brain tumor registry. Materials and Methods For the generation of this 7-year HBBTR data of all primary intracranial tumors operated, diagnosed, and registered at the Department of Pathology, Sawai ManSingh, between January 1, 2013 and December 31, 2019, was collected, analyzed, and compared with Tata Memorial Hospital, National Institute of Mental Health and Neurosciences, and Central Brain Tumor Registry of the United States. Results A total of 3,526 patients were of primary intracranial tumors. Out of which, male patients were 1,982 (56.2%), while 1,544 (43.8%) were female patients. Maximum proportion of tumors was in fifth decade. Overall, pediatric and adult patients constituted of 15.5 and 84.5% of the cases, respectively. Among all primary intracranial tumors, meningiomas (20%) were most common followed by glioblastoma multiformat (18%) and least common were germ cell tumors (0.1%) followed by pineal tumors (0.3%). In pediatric cohort astrocytic tumors (30.1%) are most common followed by embryonal tumors (20.8%), while in adults meningiomas (23.1%) were most common followed by glioblastomas (20.3%). Our registry showed similar trends of tumors with national data as compared with international data in median age of presentation. Conclusion This HBBTRs provide prevalence of primary intracranial tumors at a tertiary care center and could be a part of population-based registry.

GCT-57. ARE MELATONIN LEVELS A RELIABLE MARKER FOR INTRACRANIAL GERM CELL TUMORS POST TREATMENT DEFICIENCY?

BACKGROUND Pineal is the melatonin-producing gland, with this hormone importantly acting as a central and peripheral chronobiotic, antioxidant and in energy metabolism. The urinary dosage of 6-sulfatoxymelatonin (aMT6s), a melatonin metabolite, is an indirect marker to estimate the total melatonin nocturnal production, ranging in clinically normal individuals from 10–50 micrograms(ug). The purpose of this study was to evaluate aMT6s in patients with diagnosis of intracranial germ cell tumors (iGCT) treated at IOP/GRAACC/UNIFESP. METHODS After an interview to collect data about therapies employed and medications, night urine samples (from 8:00pm to first void in the morning) were collected and analyzed by ELISA. RESULTS Twenty patients between 5–42 years old (mean 20.9 years), all male, were analyzed. Thirteen patients had diagnosis of Germinoma, 1 with Imature Teratoma, 5 NGGCT and 2 Mature Teratoma. The first site was pineal (N=15) and bifocal (N=5). The treatment was surgery/biopsy/2º look surgery in 17 patients associated with chemotherapy/ radiotherapy, except in 2 (pure teratoma-surgery only) and 1 (chemo only). Three patients had diagnosis by tumor markers treated with chemo only (N=1) and chemotherapy/radiotherapy (N=2). The levels of aMT6s were between 0.2–3.2ug in all participants, except in one (14.8ug-biopsy, chemo and RT). CONCLUSION aMT6s levels found in most patients are below the expected for the general population suggesting that this is an appropriate marker for pineal tumors with melatonin deficiency. It may contribute to support future studies in this area and adoption of follow-up protocols, with eventual hormone supplementation and consequently improved quality of life.