Ranj Bhangoo

Primary glioblastoma with oligodendroglial differentiation has better clinical outcome but no difference in common biological markers compared with other types of glioblastoma

BACKGROUND Glioblastoma multiforme with an oligodendroglial component (GBMO) has been recognized in the World Health Organization classification-however, the diagnostic criteria, molecular biology, and clinical outcome of primary GBMO remain unclear. Our aim was to investigate whether primary GBMO is a distinct clinicopathological subgroup of GBM and to determine the relative frequency of prognostic markers such as loss of heterozygosity (LOH) on 1p and/or 19q, O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation, and isocitrate dehydrogenase 1 (IDH1) mutation. METHODS We examined 288 cases of primary GBM and assessed the molecular markers in 57 GBMO and 50 cases of other primary GBM, correlating the data with clinical parameters and outcome. RESULTS GBMO comprised 21.5% of our GBM specimens and showed significantly longer survival compared with our other GBM (12 mo vs 5.8 mo, P = .006); there was also a strong correlation with younger age at diagnosis (56.4 y vs 60.6 y, P = .005). Singular LOH of 19q (P = .04) conferred a 1.9-fold increased hazard of shorter survival. There was no difference in the frequencies of 1p or 19q deletion, MGMT promoter methylation, or IDH1 mutation (P = .8, P = 1.0, P = 1.0, respectively). CONCLUSIONS Primary GBMO is a subgroup of GBM associated with longer survival and a younger age group but shows no difference in the frequency of LOH of 1p/19q, MGMT, and IDH1 mutation compared with other primary GBM.

Co-deletion of 1p/19q is Strongly Correlated with a High Level of MGMT Promoter Methylation in High Grade Gliomas as Revealed by Pyrosequencing

Background: MGMT methylation, along with 1p/19q co-deletion and IDH1 mutation, is an important biomarker in high grade gliomas. MGMT methylation indicates an improved response to temozolomide chemotherapy; patients with 1p/19q co-deleted anaplastic oligodendrogliomas benefit preferentially from adjuvant chemotherapy. Pyrosequencing is a method that allows the level of MGMT methylation to be measured in a quantitative manner. Aim: To compare the mean MGMT promoter methylation level of high grade gliomas and correlate it with other clinical parameters and markers including 1p/19q co-deletion and mutation to IDH1or IDH2. Methods: Pyrosequencing was used to quantitatively detect the level of MGMT promoter methylation for 171 high grade gliomas mutations to IDH1 and IDH2 genes were also detected by pyrosequencing, or immunohistochemistry (n=166). Screening for 1p/19q deletion was by fluorescence in situ hybridisation (n=46). Statistical analysis was performed using R-Stats v2.15.2. Results: Higher methylation was correlated with lower grade and mutation to either IDH1 or IDH2 (27.0% vs. 16.6% p = 0.008; and 27.5 vs. 16.1 p = 0.002 respectively). 1p/19q co-deletion versus non co-deletion was associated with a particularly high level of methylation (42.2% vs. 17.7% p = 0.001). No significant differences were seen for age or gender. Conclusions: The results offer a potential explanation for the improved prognosis seen in glioma patients with 1p/19q co-deletion.

5-ALA fluorescence in intraparenchymal endodermal cysts

In recent years, new indications have been suggested for 5-ALA, particularly for cystic lesions. We report the use of 5-ALA fluorescence in an intraparenchymal supratentorial endodermal cyst of a 52-year-old female presenting with headache, progressive right side hemiparesis and anomic aphasia. She underwent an image-guided 5-ALA-assisted left minicraniotomy for fenestration of the cystic lesion into the ventricular system. The capsule of the cyst was noted to fluoresce with 5-ALA. She recovered from the previous deficits and the cyst decreased in size. To the best of our knowledge, this is the first time 5-ALA fluorescence is reported in a case of endodermal cyst.

Third-ventricle enterogenous cyst presentation mimicking a colloid cyst: uncommon presentation of a rare disease and literature review

Enterogenous cysts (ECs) are endodermal lesions resulting from splitting anomalies in the neuroenteric canal. We report the case of a 64-year-old patient who presented with a sudden headache followed by collapse. Brain computed tomography revealed a hyperdense lesion in the anterior part of the third ventricle with obstructive hydrocephalus. A presumptive diagnosis of colloid cyst was made and he underwent a right transcortical approach for lesion resection. The histopathological examination revealed an EC. ECs are common lesions in the cervical-thoracic spine but rare in the supratentorial compartment with only two previously described cases occurring in the third ventricle.