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Surgical Indications
Symptoms Symptoms of gliomas depend on which part of the central nervous system is affected. A brain glioma can cause headache, nausea, vomiting, seizures, and cranial nerve disorders as a result of increased intracranial pressure. Spinal cord gliomas can cause pain, weakness or numbness in the extremities. Gliomas do not metastasize by the bloodstream, but they can spread via the cerebrospinal fluid and cause "drop metastases" to the spinal cord.Treatment Standard therapy Treatment for brain glioma depends on the location, the cell type and the grade of malignancy. Often, treatment is a combined approach, using surgery, radiation therapy, and chemotherapy. Spinal cord tumors can be treated by surgery and radiation. Prognosis Gliomas cannot be cured. The prognosis for patients with high-grade gliomas is generally poor, and is especially so for older patients. Survival of the anaplastic astrocytoma is about three years. Glioblastoma multiforme has a worse prognosis with less than 12 month survival after diagnosis.
Small tumors 2.0 cm or less are usually incidental findings and usually does not cause any signs and symptoms. Larger tumors can cause symptoms depending on the size and location.
Meningiomas are readily visualized with contrast CT, MRI , and arteriography, all attributed to the fact that meningiomas are extra-axial and vascularized. CSF protein is usually elevated if lumbar puncture is attempted. Treatment Observation For a small tumour a regular close follow up with the patient with periodic imaging can be done. This is only possible when the tumor is small and patient does not have any neurological deficit. Observation is not recommended in tumors that are already causing symptoms. Furthermore, close follow-up with imaging is required with an observation strategy to rule out an enlarging tumor. Surgical resection Meningiomas can usually be surgically resected with permanent cure if the tumor is superficial on the dural surface and easily accessible. Transarterial embolization has become a standard preoperative procedure in the preoperative management. If tumor is not accessible or adherent to a vital structure total removal is nearly impossible. Malignant transformation is rare. Radiation therapy may include Gamma Knife, proton beam treatment, or fractionated external beam therapy. Radiation therapy is often considered for WHO Grade I meningiomas after subtotal (incomplete) tumor resections. In the case of a malignant meningioma, the current standard of care involves post-operative radiation treatment regardless of the degree of surgical resection.]This is due to the proportionally higher rate of local recurrence for these higher grade tumors. Current chemotherapies are likely not effective. Antiprogestin agents have been used, but with variable results. Recent evidence that hydroxyura has the capacity to shrink unresectable or recurrent meningiomas is being further evaluated. C. Schwannoma Schwannomas are predominantly benign tumors. In rare cases, the tumors can become malignant. The tumors can grow anywhere throughout the nervous system. The most common places for schwannoma tumors are in the brain, throughout the trunk, and the limbs Surgical intervention is the most common treatment for schwannomas.The aim of the surgery is total removal of the tumour with preservation of neural function to reduce the post operative complications. It requires sophisticated gadgets like operating microscope and intraoperative electrophysiological monitoring. Neurosurgeon-oncologists deal with malignant neural tumors, so patients with malignant schwannomas benefit greatly from multidisciplinary approach Gamma Knife Surgery It is a highly focused stereotactic Gamma Radiation to a specific area of the brain. The success rate is high and complications are very few. It can be used where surgery is difficult due to a difficult location of a tumor or potential risk of complications are very high .It can be used when there are contraindications for surgery . Also Gamma Knife can be used when there is a significant residual tumor left after a surgery. If the patient does not have any or minimal signs or symptoms due to this tumor, a close observation is the best choice. It comprises of periodic clinical check up and imaging D. Neurofibroma A neurofibroma is a benign nerve sheath tumor in the peripheral nervous system. Usually found in individuals with neurofibromatosis type 1 (NF1), a genetically-inherited disease, they can result in a range of symptoms from physical disfiguration and pain to cognitive disability. Neurofibromas arise from Schwann cells in the NF1 gene that codes for the protein neurofibromin. This protein is responsible for regulating the RAS-mediated cell growth pathway. In contrast to schwannomas, another type of tumor arising from Schwann cells, neurofibromas incorporate many additional types of cells and structural elements in addition to Schwann cells, making it difficult to identify and understand all the mechanisms through which they originate and develop. Neurofibromas have been subdivided into two broad categories: dermal and plexiform. Dermal neurofibromas are associated with a single peripheral nerve, while plexiform neurofibromas are associated with multiple nerve bundles. According to the World Health Organization classification system, dermal and plexiform neurofibromas are grade I tumors. Types of Neurofibroma:- Dermal Neurofibromas Dermal Neurofibroma, sometimes referred to as cutaneous neurofibroma, typically arise in the teenage years and are often associated with the onset of puberty. They continue to increase in number and size throughout adulthood, although there are limits to how big they get. They look like lumps on or under the skin. While dermal neurofibromas can lead to stinging, itching, pain and disfiguration. They do not undergo malignant transformation. Treatment Surgery is the most preferred choice of treatment . Dermal neurofibromas are not removed unless they are painful or causing disfigurement. E. Ependymoma Ependymoma is a tumor that arises from the ependyma, a tissue of the central nervous system. Usually, in children the location is intracranial, while in adults it is spinal. The common location of intracranial ependymoma is the fourth ventricle. Ependymomas are also seen with Neurofibromatosis Type II. Ependymomas make up about 5% of adult intracranial gliomas and up to 10% of childhood tumors of the central nervous system (CNS). Their occurrence seems to peak at age 5 years and then again at age 35. Gamma Knife Surgery - A surgery without incision In 1950 Swedish Neurosurgeon Professor Lars Leksell at Karolinska Institute in Stockholm and radiation biologist Borge Larsson of the Gustaf Wermer Institute,Uppsala University began to investigate combining radiation beams with stereotactic (guiding ) devices capable of pinpointing targets within the brain.In 1967 the first Gamma Knife device was constructed and Professor Leksell termed as `Stereotactic Radiosurgery `Professor Leksell and his colleague built his second Gamma Knife machine in 1975.It was for the Neurological service.The subsequent devices are installed in different countries. The Gamma Knife contains 201 Cobalt -60 sources approximately placed in circular array in a heavily shielded assembly.The unit directs the Gamma radiation to a target point ie. abnormal brain tissue .Patient wears a specialized helmet that is fixed to their skull so that brain tumour remains stationary at target point of Gamma rays.The powerful radiation treats the diseased brain tissue while the surrounding brain tissue is intact. It is as precise as 0.3 mm.So a relatively inoperable area can be treated safely in Gamma Knife.A single dose radiation therapy is capable of treating the brain disease. The procedure Mechanism Side effects » It is relatively safe procedure |
