A common tumour in a rare location: a single centre case series of cerebellar glioblastoma.

Although glioblastoma is the commonest primary brain tumour in adults, its location in the cerebellum is extremely rare. We present thirteen cases (3 female, 10 male; median age at presentation 56 [age range 21-77]) of surgically managed, histologically confirmed, primary cerebellar glioblastoma (cGB) over a 17 year period (2005-2022). Pre-operative radiological diagnosis was challenging given cGB rarity, although MRI demonstrated ring enhancement in all cases. Surgical management included posterior fossa craniectomy and debulking in 11 cases and burr hole biopsy in two. CSF diversion was necessary in four cases. No evidence of IDH or ATRX gene mutations was found when tested. Survival ranged from 1 to 22 months after diagnosis (mean 10.9 months). We also seek to understand why glioblastoma is rare in this location and discuss potential reasons for this. We hypothesise that increasing anatomical distance from germinal regions and decreased local endogenous neural stem cell activity (which has been associated with glioblastoma) may explain why glioblastoma is rare in the cerebellum. We hereby seek to add to the limited literature on cGB as this is the largest UK cGB series to date.

Generating Operative Workflows for Vestibular Schwannoma Resection: A Two-Stage Delphi's Consensus in Collaboration with the British Skull Base Society. Part 2: The Translabyrinthine Approach.

Objective An operative workflow systematically compartmentalizes operations into hierarchal components of phases, steps, instrument, technique errors, and event errors. Operative workflow provides a foundation for education, training, and understanding of surgical variation. In this Part 2, we present a codified operative workflow for the translabyrinthine approach to vestibular schwannoma resection. Methods A mixed-method consensus process of literature review, small-group Delphi's consensus, followed by a national Delphi's consensus was performed in collaboration with British Skull Base Society (BSBS). Each Delphi's round was repeated until data saturation and over 90% consensus was reached. Results Seventeen consultant skull base surgeons (nine neurosurgeons and eight ENT [ear, nose, and throat]) with median of 13.9 years of experience (interquartile range: 18.1 years) of independent practice participated. There was a 100% response rate across both the Delphi rounds. The translabyrinthine approach had the following five phases and 57 unique steps: Phase 1, approach and exposure; Phase 2, mastoidectomy; Phase 3, internal auditory canal and dural opening; Phase 4, tumor debulking and excision; and Phase 5, closure. Conclusion We present Part 2 of a national, multicenter, consensus-derived, codified operative workflow for the translabyrinthine approach to vestibular schwannomas. The five phases contain the operative, steps, instruments, technique errors, and event errors. The codified translabyrinthine approach presented in this manuscript can serve as foundational research for future work, such as the application of artificial intelligence to vestibular schwannoma resection and comparative surgical research.

Generating Operative Workflows for Vestibular Schwannoma Resection: A Two-Stage Delphi's Consensus in Collaboration with the British Skull Base Society. Part 1: The Retrosigmoid Approach.

Objective An operative workflow systematically compartmentalizes operations into hierarchal components of phases, steps, instrument, technique errors, and event errors. Operative workflow provides a foundation for education, training, and understanding of surgical variation. In this Part 1, we present a codified operative workflow for the retrosigmoid approach to vestibular schwannoma resection. Methods A mixed-method consensus process of literature review, small-group Delphi's consensus, followed by a national Delphi's consensus, was performed in collaboration with British Skull Base Society (BSBS). Each Delphi's round was repeated until data saturation and over 90% consensus was reached. Results Eighteen consultant skull base surgeons (10 neurosurgeons and 8 ENT [ear, nose, and throat]) with median 17.9 years of experience (interquartile range: 17.5 years) of independent practice participated. There was a 100% response rate across both Delphi's rounds. The operative workflow for the retrosigmoid approach contained three phases and 40 unique steps as follows: phase 1, approach and exposure; phase 2, tumor debulking and excision; phase 3, closure. For the retrosigmoid approach, technique, and event error for each operative step was also described. Conclusion We present Part 1 of a national, multicenter, consensus-derived, codified operative workflow for the retrosigmoid approach to vestibular schwannomas that encompasses phases, steps, instruments, technique errors, and event errors. The codified retrosigmoid approach presented in this manuscript can serve as foundational research for future work, such as operative workflow analysis or neurosurgical simulation and education.

Glioblastoma multiforme metastatic to lung in the absence of intracranial recurrence: case report.

We present the case of a 65 year old gentleman who underwent craniotomy and debulking of a left temporal glioblastoma multiforme (GBM). Post-operatively he received chemotherapy and radiotherapy with good response demonstrated on interval MRI scans. At 17 months post-diagnosis and in the absence of clinical or radiological recurrence, he presented with respiratory distress. He was found to have an exudative right-sided pleural effusion, nodular pleural thickening, a hilar mass and associated lymphadenopathy. Percutaneous pleural biopsy revealed metastatic GBM. Systemic GBM metastasis despite good response to oncological treatments and in the absence of intracranial recurrence is exceedingly rare. We review the literature concerning extra-neuraxial GBM metastasis and speculate why this phenomenon is extremely rare.

Trigeminal schwannoma presenting as a gelastic seizure: no laughing matter.

We present the case of a 66 year old gentleman with trigeminal schwannoma whose only presenting feature was a single gelastic seizure. This is the first case report of pathological laughter in trigeminal schwannoma in the absence of other trigeminal, brainstem, cerebellar or other cranial nerve dysfunction.

An unusual pituitary adenoma coexistent with bilateral meningiomas: case report.

The association of pituitary adenomas and meningioma is rare. We present the case of a 46 year old lady who initially presented with large bilateral meningiomas and acromegaly. Histology demonstrated mammosomatotroph cell adenoma co-expressing Growth Hormone. This appears to be the first description of mammosomatotroph cell adenoma associated with meningiomas in the literature.

Long-term follow-up of a large prospective cohort of patients with nonfunctioning pituitary adenomas: The outcome of a conservative management policy.

OBJECTIVE: To assess the clinical outcome of a strategy of conservative monitoring of patients with nonfunctioning pituitary adenomas (NFPA) after pituitary surgery and in patients without surgery. DESIGN: Retrospective study of outcomes, using a clinical information system. PATIENTS: An unselected, clinical series of patients seen in a single centre between 1989 and 2015. MEASUREMENTS: Review of clinical information system data to obtain details and dates of surgery, radiotherapy, pituitary imaging and outcomes. RESULTS: We identified 190 cases of NFPA. Trans-sphenoidal surgery (TSS) had been performed as primary therapy in 132 cases (all macro-adenomas). At a mean 7.6-years follow-up after TSS without immediate pituitary radiotherapy, recurrence occurred in 10.7% of cases with no visible postoperative residual adenoma, 38.8% with intrasellar and 66.7% with extrasellar residuum. Recurrence was defined as growth of residual tumour requiring intervention. On survival analysis, at 10 years, recurrence-free survival was 75% in patients with no residual tumour and 40% with intrasellar residuum. Recurrence occurred in 12.5% of 24 patients who had received postop radiotherapy. Patients were monitored conservatively without initial surgery in 65 patients. After a mean of 5-year monitoring, only 20% required intervention during follow-up (18.5% TSS) and 30.8% died of nonpituitary causes during follow-up. CONCLUSION: This study suggests that a conservative approach may be safe and appropriate in patients with NFPA if followed up with appropriate imaging surveillance, whether postoperative or without primary surgery.

Endoscopic transnasal external fistulation in recurrent cystic subdiaphragmatic craniopharyngioma: a novel technique.

The authors present a technique for the persistent external drainage of intractable subdiaphragmatic cystic recurrences with the creation of a fistula between the cyst wall epithelium and epithelium on the nasal cavity, using a pedicled nasoseptal flap as a conduit. The long-term efficacy of endoscopic transnasal external fistulation (ETEF) in controlling cystic recurrences in this patient group is addressed through a retrospective observational review of 3 male patients aged 8, 22, and 45 years with the diagnosis of recurrent cystic subdiaphragmatic craniopharyngioma who underwent the ETEF procedure between 2006 and 2009. Clinical presentation, neuroimaging, surgical interventions, and follow-up were recorded. The main outcome measure was cyst reaccumulation on MRI. Patients had a mean follow-up of 76 months (range 5-8 years) with no incidence of cystic recurrence. Follow-up imaging revealed sustained cyst involution contrary to the usual recurrent enlargement commonly seen in this patient group. Symptoms of headache and visual field defects improved post-ETEF. Long-term theoretical complications of a persistent fistula such as intracranial abscess, meningitis, or CSF leak were not observed. ETEF promotes nasalization of cystic recurrences in subdiaphragmatic craniopharyngioma. It is safe and effective, causing long-term involution of cysts and can be considered a definitive procedure.

How reliably can autoimmune hypophysitis be diagnosed without pituitary biopsy.

Autoimmune hypophysitis is a rare chronic inflammatory condition of the pituitary gland which typically presents with hypopituitarism and a pituitary mass. Cases involving anterior pituitary alone (65%) are six times more common in women, typically presenting during pregnancy or postpartum (57%). Anterior and posterior pituitary involvement (25%) are twice as common in women, and neurohypophysis alone (10%) occurs equally in both sexes. It has a prevalence of around 5 per million, an annual incidence of 1 in 7 to 9 million and in our experience represents the known or suspected cause of 0.5% of cases of hypopituitarism, <1% of pituitary masses and 2% of nonfunctioning macro lesions presenting to an endocrine clinic. However, 'missed' cases of autoimmune hypophysitis may be the aetiology of some other unexplained cases of hypopituitarism. Clinically, headache and visual disturbance are common. Anterior hypopituitarism shows a characteristic but atypical pattern of deficiency of ACTH followed by TSH, gonadotrophins and prolactin deficiency or hyperprolactinaemia. Eighteen percent of cases have evidence of another autoimmune condition. On magnetic resonance imaging (MRI), autoimmune hypophysitis is typically symmetrical and homogeneous with thickened but undisplaced stalk in contrast to typical findings with pituitary tumours. Ultimately, the histological diagnosis of autoimmune hypophysitis can only be confirmed by surgery but a presumptive diagnosis can often be made on the basis of a combination of context and clinical features, and pituitary biopsy is not always clinically necessary for effective clinical management of the patient.