What is that?
Anaplastic oligoastrocytoma, or anaplastic astrocytoma, is a malignant tumor of the brain. It is more precisely a glioma, that is to say, a tumor resulting from nervous tissue in the brain or the spinal cord. The World Health Organization classifies gliomas from I to IV, depending on their morphology and degree of malignancy. Anaplastic astrocytomas represent grade III, between grades I and II considered benign, and glioblastomas (grade IV). An anaplastic astrocytoma can either be a complication of a benign grade II tumor or develop spontaneously. It has a strong tendency to progress to glioblastoma (grade IV), and life expectancy is around two to three years, despite treatment with surgery and radiotherapy/chemotherapy and with the help of recovery groups. Anaplastic astrocytomas and glioblastomas affect 5 to 8 in 100,000 people in the general population.
Most symptoms of anaplastic oligoastrocytoma result from increased pressure in the brain, caused either by the tumor itself or by the abnormal buildup of cerebrospinal fluid it causes. Signs vary depending on the exact location and size of the tumor:
- Memory impairment, personality changes, and hemiplegia when the tumor grows in the frontal lobe;
- Seizures, impaired memory, coordination, and speech when in the temporal lobe;
- Motor disorders and sensory abnormalities (tingling and burning) when located in the parietal lobe;
- Visual disturbances when the tumor involves the occipital lobe.
The Origins of the Disease
The precise cause of anaplastic astrocytoma is not yet known, but researchers believe that it results from a combination of a genetic predisposition and environmental factors triggering the disease.
Anaplastic oligoastrocytoma is somewhat more common in men than women and often occurs between 30 and 50. However, it should be noted that the disease is likely to affect children, usually between 5 and 9 years old. Anaplastic astrocytomas and multiform glioblastomas (grades III and IV) represent approximately 10% of childhood tumors in the central nervous system (80% of these tumors being a grade I or II).
Hereditary genetic diseases such as neurofibromatosis type I (Recklinghausen’s disease), Li-Freemen syndrome, and Bourneville tuberous sclerosis increase the risk of developing an anaplastic astrocytoma.
As with many cancers, environmental factors such as exposure to ultraviolet rays, ionizing radiation, and certain chemicals, and poor diet and stress are considered risk factors.
What are The Diagnostic Procedures?
The diagnosis of astrocytoma is confirmed by X-ray imaging. (MRI) Magnetic resonance imaging and computed tomography are both standards here. Additional contrast agents are used for better identification and localization of tumors.
Since some astrocytomas cannot be accurately distinguished from other brain lesions, such as stroke (heart attack), multiple sclerosis, or lymphoma, a brain biopsy of the tumor area is taken to confirm the diagnosis.
Prevention and Treatment
The treatment of anaplastic oligoastrocytoma depends essentially on the patient’s general condition, the location of the tumor, and the speed of its progression. It involves surgery, radiotherapy, and chemotherapy, alone or in combination. The first step is to perform surgical removal of as large a part of the tumor as possible (resection), but this is not always possible due to the parameters mentioned above. Radiation therapy and possibly chemotherapy are used after surgery to remove tumor residue, such as if the malignant cells have spread into brain tissue.
The prognosis is linked to the patient’s state of health, the tumor’s characteristics, and the body’s response to chemotherapy and radiotherapy treatments. Anaplastic astrocytoma has a strong tendency to progress to glioblastoma in about two years. With standard treatment, the median survival time for people with an anaplastic astrocytoma is two to three years, which means that half of them will die before this time.
Prognosis and Life Expectancy with Anaplastic Oligo Astrocytoma
The prognosis depends mainly on the type of astrocytoma, the patient’s age, the general state of health, and the complete removal of the tumor.
Benign astrocytomas can almost always be cured with surgery. Permanent nerve damage is rare. If individual malignant tumor cells are found in the removed tissue, there is post-irradiation. In the case of inoperable tumors (due to the difficult access route), spontaneous regression may be observed in rare cases.
Minor (grade II) malignant astrocytomas, such as grade III and IV astrocytomas, cannot yet be cured. In most cases, this is followed over the years by a transformation into even smarter astrocytomas. On average, about half of patients live five years after treatment. This prognosis is reduced with the degree of malignancy to a few months for a grade IV astrocytoma.
To keep life expectancy as high as possible, precise postoperative regimens must be followed to detect and treat the tumor’s recurrence as early as possible.