Oligodendroglioma
Dongyou Liu in Tumors and Cancers, 2017
Oligodendroglioma (or oligodendroglial tumor) arises from oligodendrocytes in the central nervous system (CNS). Accounting for 10%–30% of all gliomas, oligodendroglioma encompasses WHO Grade II oligodendroglioma (70%), which shows round and uniform nuclei with crisp nuclear membranes, delicate chromatin, and small to inconspicuous nucleoli; and WHO Grade III anaplastic oligodendroglioma (30%), which displays enlarged and epithelioid cells with nuclei of increased size and pleomorphism, a more vesicular chromatin pattern and more prominent nucleoli [1]. The 2016 WHO classification of CNS tumors combines histological criteria with molecular features and separates oligodendroglioma into oligodendroglioma IDH mutant and 1p/19q codeleted (WHO Grade II), oligodendroglioma not otherwise specified (NOS) (WHO Grade II), anaplastic oligodendroglioma IDH mutant and 1p/19q codeleted (WHO Grade III), and anaplastic oligodendroglioma NOS (WHO Grade III) [1].
Genetics of brain tumors
J. K. Cowell in Molecular Genetics of Cancer, 2003
Oligodendrogliomas are a type of glioma which occur mainly in the cerebral hemispheres of adults and are derived from the oligodendrocyte cell lineage. Well differentiated oligodendrogliomas which exhibit benign cytologic features are considered grade II according to the WHO classification, while anaplastic oligodendrogliomas which exhibit abundant mitotic activity, necrosis without pseudopalisading, glomeruloid vascular proliferation are considered grade III tumors. According to data collected by the Surveillance, Epidemiology, and End Results (SEER) project, the age adjusted incidence of oligodendroglioma is 0.33 per 100 000 (Velema and Percy, 1987).
Precision medicine for brain gliomas
Debmalya Barh in Precision Medicine in Cancers and Non-Communicable Diseases, 2018
Pilocytic astrocytoma (grade I) has the highest relative survival. Glioblastoma has the poorest overall survival, with only 0.05%–4.7% of patients surviving 5 years after the diagnosis. In general, gliomas with an oligodendroglial component have increased survival, as opposed to those with an astrocytic component. Age is significantly associated with survival after diagnosis for all types of gliomas, but the effect is most pronounced for glioblastoma. Recently, it was shown in population-based parallel cohorts of diffuse low-grade gliomas that early surgical resection was associated with better overall survival than were biopsy and watchful waiting. The 22981/26981 trial by the European Organisation for Research and Treatment of Cancer/National Cancer Institute of Canada demonstrated a survival benefit for glioblastoma patients who received concurrent temozolomide with postoperative radiation, with median survival of 14.6 months for those receiving concurrent therapy versus 12.1 months for those who received radiotherapy alone (Stupp et al., 2005). This treatment regimen, known as the “Stupp protocol,” was the result of this trial and was first presented in 2004. In the years since this trial was completed, it has been established as the standard of care for primary glioblastoma. For various reasons—including tolerance of chemotherapy, access to chemotherapeutic agents, and overall performance status—not all persons with glioblastoma receive this regimen. This result was then confirmed in a large study of glioblastoma patients, and several analyses found statistically significant trends in increasing survival for glioblastoma after this development, especially in those who received surgery followed by radiation. There has been an increasing trend in survival from oligodendroglioma, which is also attributed to improvements in diagnosis and treatment. Precision medicine for brain gliomas means matching the right patient to the right treatment at the right time (Halkin, 2015). This requires gaining a deeper understanding of the specific molecular characteristics that are driving a patient's tumor growth and finding the right treatments to target those specific molecular abnormalities that are responsible for the disease. So, sequencing the patient's genome and tracking the changes in a billion biomarkers, including RNA, proteins, metabolites, and antibodies, to predict and validate disease risk are the basis of precision medicine for brain gliomas (Izci, 2014).
Anaplastic oligodendroglioma metastasizing to the bone marrow: a unique case report and literature review
Published in International Journal of Neuroscience, 2019
Vikas K. Singh, Shipra Singh, Leela Bhupalam
Oligodendrogliomas are a rare type of primary brain tumor. They are genetically defined as diffuse gliomas carrying mutation in isocitrate dehydrogenase type 1 (IDH1) or type 2 (IDH2) and codeletion of chromosomes 1p and 19q. The WHO grading system distinguishes two histopathologic grades of ODs: grade II (low-grade) and grade III (anaplastic oligodendroglioma or AO). These tumors rarely metastasize outside of central nervous system with only few cases reported in the literature. Here we present a case of an AO, which metastasized to the bone marrow and other sites within a year of diagnosis despite aggressive treatment measures. Our patient eventually succumbed to his disease, raising many questions about this rare condition, its natural course and optimal management strategy.
Multicentric high grade oligodendroglioma: a rare entity
Published in British Journal of Neurosurgery, 2019
Atul Vats, Amit Amit, Paresh Doshi
A 74 year old male presented with 1 month history of weakness in right upper limb and motor aphasia for 15 days. Magnetic resonance imaging (MRI) of the brain showed three discrete ring enhancing lesions. An image guided awake craniotomy and biopsy of a lesion was performed. The histopathological examination revealed it to be a grade III Oligodendroglioma. This was a rare case of multicentric high grade oligodendroglioma has never been reported in literature. We report such a case with relevant review of literature.
Papilloedema secondary to oligodendroglioma
Published in Clinical and Experimental Optometry, 2016
Oligodendrogliomas are rare slow‐growing asymptomatic glial tumours that usually present in patients in their fourth to sixth decades of life. Neurological symptoms that may present include nausea, headache, vomiting, diplopia, confusion, focal weakness, numbness and seizures. The treatment of oligodendroglioma tumours is based on functional status classification, lumbar puncture, imaging of the head, tumour biopsy and genetic testing. Grades II and IV oligodendroglial tumours, which have co‐deletion of the short arm of chromosome 1 (1p) and the long arm of chromosome 19 (19q) and mutations in isocitrate dehydrogenase, have the most favourable prognosis, as they respond well to neurosurgery and chemotherapy. This report will discuss a general case of papilloedema in a young patient with oligodendroglioma and the role of the optometrist in its post‐neurosurgical and chemotherapeutic care.
Related Knowledge Centers
- Astrocytoma
- Oligodendrocyte
- Brain
- Glioblastoma
- Choroid Plexus Neoplasms
- Glioma
- Ependymoma