Adult Diffuse Glioma Flashcards
Diffuse gliomas are most common primary intra-axial brain tumors. Astrocytes typically appear in the white matter (e.g., centrum semiovale) and traverses through white matter tract. A patient presenting in OPD with history of seizure, his/her CT of brain showing low density lesion, MRI showing abnormal
signal on T2WI with no enhancement, and no or very little mass effect is diagnosed as astrocytoma, IDH mutant, grade 2 tumor. Following are the most common locations for this tumor except?
● A. Temporal lobe
● B. Occipital lobe
● C. Posterior frontal lobe
● D. Right anterior parietal lobe
● E. Left anterior parietal lobe
B. Occipital lobe
Gliomas can spread through CSF pathways (subarachnoid seeding) in 10 to 25% of high-grade gliomas and rarely may spread systemically. Gliomas can also spread from one part of brain to other part through white matter track. Which of the following statements is incorrect?
● A. Bilateral frontal lobe involvement occurs through genu or body of corpus callosum
● B. Bilateral occipital or parietal lobes involvement occurs through splenium of corpus callosum
● C. Midbrain involvement of tumor occurs through internal capsule
● D. Simultaneous frontal and temporal occurrence of tumor occurs through uncinate fasciculus
● E. Interthalamic adhesions cause bilateral thalamic gliomas
C. Midbrain involvement of tumor occurs through internal capsule
A patient presents in neurosurgical OPD with signs and symptoms of raised ICP. CT of brain was done which showed brain tumor in frontal lobe and solid enhancement on contrast. Microvascular proliferation was seen, and Ki-67 and MIB-1 index was found to be more than 7 to 9% in this tumor on biopsy, which showed it was astrocytoma, IDH mutant, grade 4 tumor. What is the essential diagnostic criterion for IDH mutant tumors?
● A. A diffusely infiltrating tumor with IDH1 codon 132 or IDH2 codon 172 missense mutation with loss of nuclear ATRX expression or ATRX mutation
● B. A diffusely infiltrating tumor with IDH1 codon 132 or IDH2 codon 172 missense mutation with exclusion of combined whole arm deletions of 1p and 19q
● C. Astrocytic differentiation by morphology with TP 53 mutation
● D. IDH mutation with Aa and B
● E. A and B
E. A and B
Significant prognosticators for gliomas are postoperative residual tumor volume and preoperative tumor size. Following
factors show worse prognosis of glioma except?
● A. Age more than 40 years
● B. No neurologic deficit prior to surgery
● C. Largest tumor diameter of more than or equal to 6 cm
● D. Tumor crossing midline
● E. Subtotal resection
B. No neurologic deficit prior to surgery
A patient presents with seizure in your clinic for the first time. You advised plain CT of brain which showed hypodense to isodense lesion with calcifications. MRI of brain showed poor demarcation with T1 hypointense lesion and hyperintense on T2 with no enhancement on contrast. The essential diagnostic criteria for diagnosis of oligodendroglioma is a diffusely infiltrating tumor WITH IDH1 codon 132 or IDH2 codon 172 missense mutation WITH combined whole arm deletions of 1p and 19 q. Following features in this patient will characterize this lesion as grade 3 tumor except?
● A. Low mitotic activity
● B. High cellularity
● C. Marked cytological atypia
● D. Pathologically microvascular proliferation
● E. Necrosis with and without palisading
A. Low mitotic activity
A patient presents with signs of raised ICP in your clinic. You advised urgent MRI which showed lesion with large area of central necrosis and ring enhancement pattern on contrast. Most common locations of these lesions are temporal lobe, parietal lobe, frontal lobe, and occipital lobe in descending order. All of the following are included in essential diagnostic criteria for glioblastoma IDH wildtype except?
● A. DNA methylation of glioblastoma
● B. A diffusely infiltrating astrocytic glioma
● C. IDH wildtype and H3 wildtype
● D. Microvascular proliferation or necrosis
● E. TERT promoter mutation or EGFR gene amplification or +7/−10 chromosome copy number alteration
A. DNA methylation of glioblastoma
High grade diffuse gliomas (WHO grades 3 and 4) show improved prognosis with which of the following?
● A. Preoperative performance status, for example, Karnofsky score (KPS) more than 60
● B. Old-aged patients
● C. Nonmethylation of MGMT promotor gene
● D. IDH1 mutation
● E. All of the above
D. IDH1 mutation
Gross total resection (GTR) is complete removal of enhancing portions of the tumor and any nonenhancing portion contained within, as verified by postoperative contrast imaging within 48 hours of surgery, or removal of high intensity lesion
or very low intensity on T1 MRI in case of nonenhancing lesion. Surgical goals in case of diffuse glioma surgery are to obtain adequate tissue for histological and molecular study and cytoreduction or maximal safe resection with the goal of GTR when feasible. What are relative contraindications of surgery?
● A. Extensive dominant lobe high grade glioma
● B. Lesion with significant bilateral involvement
● C. Karnofsky score less than 70
● D. Multicentric glioma
● E. All of the above
E. All of the above
A patient presents with diffuse astrocytoma grade 2 near eloquent area of brain. The extent of resection of this tumor can be increased or complication can be decreased by using which method?
● A. Image guidance or stereotactic radiosurgery
● B. Preoperative mapping like functional MRI or diffusion tensor imaging
● C. Intraoperative mapping with awake craniotomy
● D. Intraoperative dyes like indocyanine green and 5 amino levulinic acid
● E. All of the above
E. All of the above
Adjuvant radiotherapy or chemotherapy in patients with grade 2 glioma is recommended only if there is subtotal resection or early progression. Which of the following is true regarding Stupp regimen for diffuse glioma patients?
● A. It consists of radiotherapy (fractionated focal radiation) at a dose of 2 Gy per fraction once daily 5 days per week over a period of 6 weeks, for a total dose of 60 Gy
● B. A + Chemotherapy is given such as temozolomide at a dose of 75 g/m2/d, 7 days per week till end of radiotherapy
● C. B + After first 6 weeks of chemotherapy and radiotherapy 4 weeks gap is given and then chemotherapy is given in 6 cycles each consisting of 5 days of TMZ repeated every 28 days at a dose of 150 mg/m2/d for first cycle then 200 mg/m2/
d for rest of cycles
● D. C + Cytoreductive surgery
● E. All of the above
C. B + After first 6 weeks of chemotherapy and radiotherapy 4 weeks gap is given and then chemotherapy is given in 6 cycles each consisting of 5 days of TMZ repeated every 28 days at a dose of 150 mg/m2/d for first cycle then 200 mg/m2/
d for rest of cycles
Hypermethylation of the MGMT promoter gene (consists of > 30% methylation) causes reduced levels of MGMT activity. Tumors with reduced levels of MGMT activity are more susceptible to cytotoxic effects of temozolomide. This leads to longer overall survival of these patients from 15.2 months in those
without hypermethylation of MGMT to how long?
● A. 20.2 months
● B. 22.2 months
● C. 25.2 months
● D. 28.2 months
● E. 30.2 months
C. 25.2 months
Pseudoprogression is an increase in contrast enhancing areas on postoperative MRI after giving Stupp regimen due to radiation necrosis or tumor cells killed by chemotherapy. Hence, such enhancing areas within first 6 months of Stupp regimen are considered pseudoprogression. Which of the following studies is helpful with very low specificity and sensitivity to differentiate pseudoprogression from tumor recurrence?
● A. MR perfusion
● B. DWI with higher ADC
● C. MR spectroscopy
● D. PET
● E. All of the above
E. All of the above
