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The goal of radiation therapy is to kill tumor cells while leaving normal brain tissue unharmed. In standard external beam radiation therapy, multiple treatments of standard-dose "fractions" of radiation are applied to the brain. This process is repeated for a total of 10 to 30 treatments, depending on the type of tumor. This additional treatment provides some patients with improved outcomes and longer survival rates.
Radiosurgery is a treatment method that uses computerized calculations to focus radiation at the site of the tumor while minimizing the radiation dose to the surrounding brain. Radiosurgery may be an adjunct to other treatments, or it may represent the primary treatment technique for some tumors. Forms used include stereotactic radiosurgery, such as Gamma knife, Cyberknife or Novalis Tx radiosurgery.
Radiotherapy may be used following, or in some cases in place of, resection of the tumor. Forms of radiotherapy used for brain cancer include external beam radiation therapy, the most common, and brachytherapy and proton therapy, the last especially used for children.
Radiotherapy is the most common treatment for secondary brain tumors. The amount of radiotherapy depends on the size of the area of the brain affected by cancer. Conventional external beam "whole-brain radiotherapy treatment" (WBRT) or "whole-brain irradiation" may be suggested if there is a risk that other secondary tumors will develop in the future. Stereotactic radiotherapy is usually recommended in cases involving fewer than three small secondary brain tumors.
People who receive stereotactic radiosurgery (SRS) and whole-brain radiation therapy (WBRT) for the treatment of metastatic brain tumors have more than twice the risk of developing learning and memory problems than those treated with SRS alone.
The primary and most desired course of action described in medical literature is surgical removal (resection) via craniotomy. Minimally invasive techniques are becoming the dominant trend in neurosurgical oncology. The prime remediating objective of surgery is to remove as many tumor cells as possible, with complete removal being the best outcome and cytoreduction ("debulking") of the tumor otherwise. In some cases access to the tumor is impossible and impedes or prohibits surgery.
Many meningiomas, with the exception of some tumors located at the skull base, can be successfully removed surgically.
Most pituitary adenomas can be removed surgically, often using a minimally invasive approach through the nasal cavity and skull base (trans-nasal, trans-sphenoidal approach). Large pituitary adenomas require a craniotomy (opening of the skull) for their removal. Radiotherapy, including stereotactic approaches, is reserved for inoperable cases.
Several current research studies aim to improve the surgical removal of brain tumors by labeling tumor cells with 5-aminolevulinic acid that causes them to fluoresce. Postoperative radiotherapy and chemotherapy are integral parts of the therapeutic standard for malignant tumors. Radiotherapy may also be administered in cases of "low-grade" gliomas when a significant tumor burden reduction could not be achieved surgically.
Multiple metastatic tumors are generally treated with radiotherapy and chemotherapy rather than surgery and the prognosis in such cases is determined by the primary tumor, and is generally poor.
Likely, current chemotherapies are not effective. Antiprogestin agents have been used, but with variable results. A 2007 study of whether hydroxyurea has the capacity to shrink unresectable or recurrent meningiomas is being further evaluated.
Radiation therapy may include photon-beam or proton-beam treatment, or fractionated external beam radiation. Radiosurgery may be used in lieu of surgery in small tumors located away from critical structures. Fractionated external-beam radiation also can be used as primary treatment for tumors that are surgically unresectable or, for patients who are inoperable for medical reasons.
Radiation therapy often is considered for WHO grade I meningiomas after subtotal (incomplete) tumor resections. The clinical decision to irradiate after a subtotal resection is somewhat controversial, as no class I randomized, controlled trials exist on the subject. Numerous retrospective studies, however, have suggested strongly that the addition of postoperative radiation to incomplete resections improves both progression-free survival (i.e. prevents tumor recurrence) and improves overall survival.
In the case of a grade III meningioma, the current standard of care involves postoperative 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. Grade II tumors may behave variably and there is no standard of whether to give radiotherapy following a gross total resection. Subtotally resected grade II tumors should be radiated.
Systemic (intravenous or oral) chemotherapy and intrathecal chemotherapy: Intrathecal therapy is when injection is done directly to the spinal cord into the sub-arachnoid space to avoid the Blood-Brain-Barrier (BBB) and gain direct access to the CSF. Intrathecal Therapy is preferred since intravenous chemotherapy do not penetrate the BBB. The most common chemicals used are liposomal cytarabine (DepoCyte) and intrathecal methotrexate (MTX).
In combination, intrathecal chemotherapy most often comprises methotrexate, cytarabine, thiotepa and steroids. Ventriculoperitoneal shunts may also be applied with chemotherapy to avoid invasive surgery to gain access to the CSF.
An example of treatment:
Intrathecal MTX injection at a dose of 15 mg/day for 5 days every other week with hydrocortisone acetate injecting IT on day one to prevent arachnoiditis, the inflammation of the arachnoid. MTX administration is continued until neurological progression or relapse occurred. Systemic chemotherapy, radiotherapy, and surgery are performed depending on the need of the patient.
Risks of treatments:
Both Chemotherapy and Radiotherapy are harmful to the body and most definitely the brain. Caution must be utilized in treating patients with NM. Another factor that makes treatment difficult is that there is no suitable method to evaluate the disease progression.
There is no standard treatment that has been established for NM thus treatments are almost always palliative.
Radiotherapy:
This method is used mostly for focal type of NM due to the nature of damage and success rate associated with the treatment. Radiotherapy targets and tumor and destroys the collective tissues of cancerous cells.
Surgery is often the treatment of choice. Total resection (removal of the tumor) is often possible. However, the best choice of treatment will depend on many individual factors, including:
- The patient's medical history and overall health condition
- The type, location, and size of the tumor
- The patient's age
- How well the patient tolerates specific medications, procedures, or therapy
- How slowly or quickly the tumor is expected to progress
If surgery is performed and the tumor is completely resected, further treatment may not be required. The patient will, however, need repeated MRIs to monitor for tumor re-growth.
For tumors that recur, another surgical resection might be attempted. For tumors that could not be completely removed, radiation therapy may also be recommended. Also called radiotherapy, this treatment uses high-energy radiation to damage or kill cancer cells and shrink tumors.
Symptoms of PXA may disappear, or improve progressively, after treatment. For example:
- Symptoms related to increased pressure in the brain often disappear after surgical removal of the tumor.
- Effects like seizures might progressively improve as recovery progresses.
- Steroid treatment is often used to control tissue swelling that may occur before and after surgery.
Because ganglioneuromas are benign, treatment may not be necessary, as it would expose patients to more risk than leaving it alone. If there are symptoms or major physical deformity, treatment usually consists of surgery to remove the tumor.
Chemotherapy is the preferred secondary treatment after resection. The treatment kills astroblastoma cells left behind after surgery and induces a non-dividing, benign state for remaining tumor cells. Normally, chemotherapy is not recommended until the second required resection, implying that the astroblastoma is a high-grade tumor continuing to recur every few months. A standard chemotherapy protocol starts with two rounds of nimustine hydrochoride (ACNU), etoposide, vincristine, and interferon-beta. The patient undergoes a strict drug regimen until another surgery is required. By the third surgery, should recurrence in the astroblastoma occur, a six-round program of ifosfamide, cisplatin, and etoposide will "shock" the patient's system to the point where recurrence halts. Unfortunately, chemotherapy may not always be successful with patients requiring further resection of the tumor, since the tumor cell begins to show superior vasculature and a strong likelihood of compromising a patient's well-being. Oral ingestion of temozolomide for at-home bedside use may be preferred by the patient.
Treatment options include surgery, radiotherapy, radiosurgery, and chemotherapy.
The infiltrating growth of microscopic tentacles in fibrillary astrocytomas makes complete surgical removal difficult or impossible without injuring brain tissue needed for normal neurological function. However, surgery can still reduce or control tumor size. Possible side effects of surgical intervention include brain swelling, which can be treated with steroids, and epileptic seizures. Complete surgical excision of low grade tumors is associated with a good prognosis. However, the tumor may recur if the resection is incomplete, in which case further surgery or the use of other therapies may be required.
Standard radiotherapy for fibrillary astrocytoma requires from ten to thirty sessions, depending on the sub-type of the tumor, and may sometimes be performed after surgical resection to improve outcomes and survival rates. Side effects include the possibility of local inflammation, leading to headaches, which can be treated with oral medication. Radiosurgery uses computer modelling to focus minimal radiation doses at the exact location of the tumor, while minimizing the dose to the surrounding healthy brain tissue. Radiosurgery may be a complementary treatment after regular surgery, or it may represent the primary treatment technique.
Although chemotherapy for fibrillary astrocytoma improve overall survival, it is effective only in about 20% of cases. Researchers are currently investigating a number of promising new treatment techniques including gene therapy, immunotherapy, and novel chemotherapies.
Treatment typically consists of radiotherapy and steroids for palliation of symptoms. Radiotherapy may result in minimally extended survival time. Prognosis is very poor, with only 37% of treated patients surviving one year or more. Topotecan has been studied in the treatment of brainstem glioma, otherwise, chemotherapy is probably ineffective, though further study is needed.
Scheduling of drug treatments and combination treatment can have substantial impact on treatment efficacy.
Dexamethasone (a potent glucocorticoid) in doses of 16 mg/day may reduce edema around the lesion and protect the cord from injury. It may be given orally or intravenously for this indication.
Surgery is indicated in localised compression as long as there is some hope of regaining function. It is also occasionally indicated in patients with little hope of regaining function but with uncontrolled pain. Postoperative radiation is delivered within 2–3 weeks of surgical decompression. Emergency radiation therapy (usually 20 Gray in 5 fractions, 30 Gray in 10 fractions or 8 Gray in 1 fraction) is the mainstay of treatment for malignant spinal cord compression. It is very effective as pain control and local disease control. Some tumours are highly sensitive to chemotherapy (e.g. lymphomas, small-cell lung cancer) and may be treated with chemotherapy alone.
Once complete paralysis has been present for more than about 24 hours before treatment, the chances of useful recovery are greatly diminished, although slow recovery, sometimes months after radiotherapy, is well recognised.
The median survival of patients with metastatic spinal cord compression is about 12 weeks, reflecting the generally advanced nature of the underlying malignant disease.
Chemotherapy is typically limited to patients with recurrent central neurocytoma. The course of chemotherapy used for CNC is one of two platinum-based regimes. The two regimes are:
- Carboplatin + VP-16 + ifosfamide
- cisplatin + VP-16 + cyclophosphamide
Because chemotherapy is used in rare cases there is still information to be gathered as to the efficacy of chemotherapy to treat benign CNC. Therefore, recommendations must be viewed as limited and preliminary.
Treatment of metastatic breast cancer is currently an active area of research. Several medications are in development or in phase I/II trials. Typically new medications and treatments are first tested in metastatic cancer before trials in primary cancer are attempted.
Another area of research is finding combination treatments which provide higher efficacy with reduced toxicity and side effects.
Experimental medications:
- sorafenib a combined Tyrosine protein kinases inhibitor.
Conventional radiotherapy, limited to the involved area of tumour, is the mainstay of treatment for DIPG. A total radiation dosage ranging from 5400 to 6000 cGy, administered in daily fractions of 150 to 200 cGy over 6 weeks, is standard. Hyperfractionated (twice-daily) radiotherapy was used previously to deliver higher radiation dosages, but did not lead to improved survival. Radiosurgery (e.g., gamma knife or cyberknife) has no role in the treatment of DIPG.
Unlike most brain tumors, brainstem glioma is not often treated with neurosurgery due to complications in vital parts of the brain. More often, it is treated with chemotherapy and/or radiation therapy (though past use of radiation therapy has yielded mixed results.)
There are several new clinical trials in process. One such trial is dendritic cell immunotherapy which uses the patient’s tumor cells and white blood cells to produce a chemotherapy that directly attacks the tumor.
However, these treatments do produce side effects; most often including nausea, the breakdown of the immune system, and fatigue. Hair loss can occur from both chemotherapy and radiation, but usually grows back after chemotherapy has ceased. Steroids such as Decadron may be required to treat swelling in the brain. Decadron can lead to weight gain and infection. Patients may also experience seizures, which need to be treated to avoid complications. For some patients there is a chance of a neurological break down, this can include, but is not limited to, confusion and memory loss.
The use of topotecan has been investigated.
Radiation therapy selectively kills astroblastoma cells while leaving surrounding normal brain tissue unharmed. The use of radiation therapy after an astroblastoma excision has variable results. Conventional external beam radiation has both positive and negative effects on patients, but it is not recommended at this point to treat all types. All in all, the radiosensitivity of astroblastoma to therapy remains unclear, since some research advocate its effectiveness while others diminish the effects. Future studies must be done on patients with both total excision and sub-excision of the tumor to accurately assess whether radiation benefits patients under different circumstances.
The mainstay of treatment is surgical excision. Two adjuvant therapeutic strategies are Stereotactic surgery (SRS) and fractionated convention radiotherapy (FCRT). Both are highly effective means of treatment.
For recurrent high-grade glioblastoma, recent studies have taken advantage of angiogenic blockers such as bevacizumab in combination with conventional chemotherapy, with encouraging results.
Treatment for brain gliomas depends on the location, the cell type, and the grade of malignancy. Often, treatment is a combined approach, using surgery, radiation therapy, and chemotherapy. The radiation therapy is in the form of external beam radiation or the stereotactic approach using radiosurgery. Spinal cord tumors can be treated by surgery and radiation. Temozolomide, a chemotherapeutic drug, is able to cross the blood–brain barrier effectively and is currently being used in therapy for high-grade tumors.
Surgery is not always recommended for syringomyelia patients. For many patients, the main treatment is analgesia. Physicians specializing in pain management can develop a medication and treatment plan to ameliorate pain. Medications to combat any neuropathic pain symptoms such as shooting and stabbing pains (e.g. gabapentin or pregabalin) would be first-line choices. Opiates are usually prescribed for pain for management of this condition. Facet injections are not indicated for treatment of syringomyelia.
Drugs have no curative value as a treatment for syringomyelia. Radiation is used rarely and is of little benefit except in the presence of a tumor. In these cases, it can halt the extension of a cavity and may help to alleviate pain.
In the absence of symptoms, syringomyelia is usually not treated. In addition, a physician may recommend not treating the condition in patients of advanced age or in cases where there is no progression of symptoms. Whether treated or not, many patients will be told to avoid activities that involve straining.
Since the natural history of syringomyelia is poorly understood, a conservative approach may be recommended. When surgery is not yet advised, patients should be carefully monitored. Periodic MRI's and physical evaluations should be scheduled at the recommendation of a qualified physician.
The role of chemotherapy in DIPG remains unclear. Studies have shown little improvement in survival, although efforts (see below) through the Children's Oncology Group (COG), Paediatric Brain Tumour Consortium (PBTC), and others are underway to explore further the use of chemotherapy and other drugs. Drugs that increase the effect of radiotherapy (radiosensitizers) have shown no added benefit, but promising new agents are under investigation. Immunotherapy with beta-interferon and other drugs has also had little effect in trials. Intensive or high-dose chemotherapy with autologous bone marrow transplantation or peripheral blood stem cell rescue has not demonstrated any effectiveness in brain stem gliomas. Future clinical trials may involve medicines designed to interfere with cellular pathways (signal transfer inhibitors), or other approaches that alter the tumor or its environment.
The evidence for the use of medical interventions for lumbar spinal stenosis is poor. Injectable but not nasal calcitonin may be useful for short term pain relief. Epidural blocks may also transiently decrease pain, but there is no evidence of long-term effect. Adding steroids to these injections does not improve the result; the use of epidural steroid injections (ESIs) is controversial and evidence of their efficacy is contradictory.
Non-steroidal anti-inflammatory drugs (NSAIDs), muscle relaxants and opioid analgesics are often used to treat low back pain, but evidence of their efficacy is lacking.