A brief review of skull base chordomas.

Skull base chrodomas are slow growing neoplasms usually located along the midline. They display a locally invasive nature with possibilities of extracranial metastasis. Presentation is usually late and depends upon the location and extent of the tumour. Management aims at gross total resection via open microsurgical or endoscopic approach followed by adjuvant radiotherapy. Prognosis may be good for the classical and chondroid subtypes but remains poor for de-differentiated type.

Glioblastoma multiforme at internal auditory canal.

Background: Glioblastomas are the most common adult primary brain tumor present supratentorially. The presence of true extra-axial GBM infratentorially, especially in the internal auditory canal, is extremely rare with only three cases reported previously in the literature. We report the fourth case of primary internal auditory canal/cerebellopontine angle (CPA) glioblastoma which initially mimicked vestibular schwannoma on the basis of its location and presentation. Case Description: A 65-year-old male presented with headache, vertigo, and progressive right ear deafness for 5 months. His preoperative magnetic resonance imaging findings were consistent with vestibular schwannoma. Maximum safe resection (near total) was done. The final histopathology report showed glioblastoma multiforme. Conclusion: As per our knowledge, this is the fourth reported case of an extra-axial VIII cranial nerve glioblastoma located in internal auditory canal. Hence, despite being very rare, they should be considered as a differential in tumors at CPA.

Mature teratoma of the cisterna magna in an adult patient.

Background: Teratomas are a rare subgroup of CNS germ cell tumors and are histologically classified into mature teratomas, immature teratomas, and teratomas with malignant transformation. CNS teratomas are infrequently found in the posterior fossa and pure mature teratomas of posterior fossa are rare especially in adults. We present a case of a young adult female with a mature teratoma in the cisterna magna. Case Description: A 26-year-old female presented to the neurosurgery clinic with headache, nausea and vomiting for the past 1 year. She was found to have dysdiadochokinesia on neurological examination. Brain magnetic resonance imaging scan showed a-well defined lesion, hyperintense on T1 and hypointense on T2-weighted sequences located within the cisterna magna. She underwent a suboccipital craniotomy with resection of lesion. Histopathology confirmed the diagnosis of mature cystic teratoma. Conclusion: Mature teratomas located in the posterior fossa among adults are rare in the literature. We report the second case of mature teratoma in the cisterna magna of an adult patient.

Postoperative cerebro spinal fluid diversion in patients with third ventricular colloid cysts.

Colloid cysts are a group of CNS neoplasms that usually present with features of CSF flow obstruction. The treatment is by microsurgical, endoscopic or stereotactic techniques. Hydrocephalus usually resolves postoperatively, but in around 3-7% of cases symptoms persist and ultimately require CSF diversion. Several factors such as operative approach, cyst size, operative time, intraoperative bleeding may influence the need for CSF diversion but most of these are yet to be statistically proven. Existing literature is mainly focused on incidence of CSF diversion after resection of colloid cyst rather than the factors which may predict its necessity and extensive research is required to accurately determine these factors.

Role of surgery in multifocal glioblastoma.

The management of multifocal glioblastomas is a point of constant discussion amongst neuro-oncologists. Best outcomes in glioblastoma management come from gross total resection (GTR) followed by concomitant radiation and chemotherapy (CCRT). Multifocal disease is resistant to GTR. Conventional management of these lesion is usually biopsy only followed by CCRT. Recent evidence has shown that there may be some benefit to attempting GTR of the largest lesion whenever safe to do so.

Endoscopic surgical treatment for primary spinal lesions.

Primary spinal cord tumours are infrequently encountered CNS neoplasms and can be broadly classified into intradural intramedullary and intradural extramedullary lesions. Resection of these lesions was traditionally done via open surgical access almost always with microscope assistance. With the advent of minimally invasive surgical techniques, endoscopic excision of these lesions has been attempted for selected tumours. Available literature mainly deals with retrospective reviews on small number of patients; therefore, extensive research is required to establish safety and efficacy of endoscopic approach for excision of primary spinal tumours.

Nanomedicine in the treatment of Glioblastoma.

The current standard of care in glioblastoma management is surgery followed by chemotherapy and radiotherapy. Temozolomide is an alkylating agent most commonly used with a few other second line options. The efficacy of systemic chemotherapy in brain malignancies is limited due to the nature of the blood-brain barrier. Nanomedicine offers one avenue of improving drug delivery to these tumours in a more focussed and effective way in higher doses than currently possible, while simultaneously reducing systemic toxicity.

Management of paediatric intracranial ependymoma.

Intracranial ependymoma are relatively common paediatric brain tumours, but their eloquent location and high recurrence rate pose a significant challenge. Gross total resection or maximum safe resection followed by adjuvant radiotherapy are currently the standard recommended treatment, although there is still nearly 50% recurrence risk at 5 years. Chemotherapy has shown some promising results after recent advances in molecular understanding of ependymomas, but needs further evaluation before it could be added to the treatment regime.

Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration for PD-L1 Testing in Non-small Cell Lung Cancer.

BACKGROUND: Programmed death-ligand 1 (PD-L1) expression on cancer cells is a clinically important biomarker to select patients with non-small cell lung cancer (NSCLC) for treatment with programmed death-1/PD-L1 inhibitors. Clinical trials of immunotherapy in patients with NSCLC have required histologic evidence for PD-L1 testing; in clinical practice, cytologic samples commonly are acquired in patients with advanced disease. RESEARCH QUESTION: This study aims to investigate whether endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) samples are adequate for PD-L1 testing in NSCLC. STUDY DESIGN AND METHODS: This study investigates the sampling adequacy of EBUS-TBNA for PD-L1 testing when compared with other methods. Furthermore, the relationship between clinicopathologic characteristics and PD-L1 expression in the study population have been examined. Five hundred seventy-seven NSCLC specimens were analyzed from consecutive patients with NSCLC across six centers in the United Kingdom and one center in the United States between January 2015 and December 2016. RESULTS: In the EBUS-TBNA group (189 specimens), the overall percentage of patients with successful PD-L1 testing was 94.7%. There was no significant difference in sampling adequacy with other methods of tissue acquisition. Older patients had higher failure rates of PD-L1 testing (OR, 1.06; P = .008). In multivariate analysis, advanced N-stage (P = .048) and presence of brain metastasis (P < .001) were associated with high PD-L1 expression. INTERPRETATION: This large multicenter study shows that EBUS-TBNA provides samples adequate for PD-L1 testing and that advanced N stage and the presence of brain metastasis are associated with high PD-L1 expression.

Clinical demonstration of efficiency and reversibility of hypoxic pulmonary vasoconstriction in a patient presenting with unilateral incomplete bronchial occlusion.

Although hypoxic pulmonary vasoconstriction is a well-recognized physiological phenomenon it is unusual to observe and assess its efficiency in clinical practice. Here, we report the case of a 50-year-old female who presented with unilateral incomplete bronchial occlusion due to a carcinoid tumor involving the left main bronchus in the absence of atelectasis. Ventilation-perfusion imaging revealed absent ventilation and perfusion to the left lung. She underwent bronchotomy and removal of the tumor. One month after the operation a further ventilation-perfusion lung scan revealed complete restoration of ventilation to the left lung and almost complete recovery of the perfusion. This unusual case demonstrates the marked efficiency of hypoxic pulmonary vasoconstriction at the level of a single lung and its reversible nature following relief of regional hypoxia.