Anaplastic oligodendroglioma
Anaplastic oligodendroglioma[Surgery|] is a neuroepithelial tumor which is believed to originate from oligodendrocytes, a cell type of the glia. In the World Health Organization classification of brain tumors, anaplastic oligodendrogliomas are classified as grade III. In the course of the disease, it can degenerate into highly malignant oligodendroglioma, grade IV. The vast majority of oligodendrogliomas occur sporadically, without a confirmed cause and without inheritance within a family.
Symptoms
Symptoms of anaplastic oligodendroglioma may include:- Seizure
- Headache
- Weakness on one side of the body
- Language difficulties
- Behavior and personality changes
- Balance and movement problems
- Memory problems.
Pathogenesis
The anaplastic oligodendroglioma belongs to the group of diffuse glioma and arises in the central nervous system from precursor stem cells of the oligodendrocytes. This tumor occurs primarily in middle adulthood with a frequency peak in the 4th and 5th decade of life.Diagnosis
The most important diagnostic procedure is magnetic resonance imaging. Occasionally, outside of routine diagnostics, the metabolism in the tissue is shown using positron emission tomography. The diagnosis is confirmed by a fine tissue examination following anoperation. Anaplastic oligodendrogliomas often show a loss of genetic material. About 50 to 70% of WHO grade III anaplastic oligodendrogliomas have combined allele losses on the short arm of chromosome 1 and the long arm of chromosome 19.
This change is mostly referred to as "1p / 19q Co Deletion". It can be seen as favorable for the patient and makes a response to radiation or chemotherapy more likely. The designation of grade III oligodendroglioma generally subsumes the previous diagnoses of anaplastic or malignant oligodendroglioma.
Treatment
Surgery can help reduce symptoms caused by the tumor. As complete as possible removal of the tumor visible on the MRI is preferred, provided the location of the tumor allows this. Since typically the cells of an anaplastic oligodendroglioma have already migrated into the surrounding healthy brain tissue at the time of diagnosis, a complete surgical removal of all tumor cells is not possible. The "1p / 19q Codeletion" marker plays an increasingly important role in the selection of therapy and therapy combinations.Because this tumor is an "indolent condition" and the potential morbidity associated with neurosurgery, chemotherapy and radiation therapy, most neuro-oncologists will initially pursue a course of watchful waiting and treat patients symptomatically. Symptomatic treatment often includes the use of anticonvulsants for seizures and steroids for brain swelling. For further treatment, radiation or chemotherapy with temozolomide or a chemotherapy with Procarbazine, CCNU and Vincristine has been shown to be effective and was the most commonly used chemotherapy regimen used for treating anaplastic oligodendrogliomas.