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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.
There is not much evidence supporting the claim that radiotherapy is a beneficial and effective means of treatment. Typically, radiotherapy is used postoperatively in respect to whether or not a partial or complete excision of the tumor has been accomplished. The histopathological features of CNC, neuronal differentiation, low mitotic activity, absence of vascular endothelial proliferation, and tumor necrosis, suggest that the tumor may be resistant to ionizing radiation. However, when radiotherapy is used, whole brain or involved-field treatment is given. This method utilizes a standard fractionation schedule and a total tumor dose of 50-55 Gy. Gamma knife surgery is a form of radiotherapy, more specifically radiosurgery that uses beams of gamma rays to deliver a certain dosage of radiation to the tumor. Gamma knife surgery is incredibly effective at treating neurocytoma and maintaining tumor control after the procedure when a complete excision has been performed. Some studies have found that the success rate of tumor control is around 90% after the first five years and 80% after the first ten years. Gamma knife surgery is the most recorded form of radiotherapy performed to treat remnants of the CNC tumor after surgery.
Total resection of the tumour, followed by radiation therapy is the standard treatment modality. Medulloepithelioma of the ciliary body may necessitate enucleation of the eye. Radiation therapy alone may prolong survival. Aggressive chemotherapy with autologous bone marrow transplant is used for metastatic medulloepitheliomas.
Chemotherapy is often used as part of treatment. Evidence of benefit, however, is not clear as of 2013. A few different chemotherapeutic regimens for medulloblastoma are used, but most involve a combination of lomustine, cisplatin, carboplatin, vincristine, or cyclophosphamide. In younger patients (less than 3–4 years of age), chemotherapy can delay, or in some cases possibly even eliminate, the need for radiotherapy. However, both chemotherapy and radiotherapy often have long-term toxicity effects, including delays in physical and cognitive development, higher risk of second cancers, and increased cardiac disease risks.
Treatment begins with maximal surgical removal of the tumor. The addition of radiation to the entire neuraxis and chemotherapy may increase the disease-free survival. Some evidence indicates that proton beam irradiation reduces the impact of radiation on the cochlear and cardiovascular areas and reduces the cognitive late effects of cranial irradiation.
This combination may permit a 5-year survival in more than 80% of cases. The presence of desmoplastic features such as connective tissue formation offers a better prognosis. Prognosis is worse if the child is less than 3 years old, degree of resection is an inadequate , or if any CSF, spinal, supratentorial, or systemic spread occurs. Dementia after radiotherapy and chemotherapy is a common outcome appearing two to four years following treatment. Side effects from radiation treatment can include cognitive impairment, psychiatric illness, bone growth retardation, hearing loss, and endocrine disruption. Increased intracranial pressure may be controlled with corticosteroids or a ventriculoperitoneal shunt.
Children with cerebellar pilocytic astrocytoma may experience side effects related to the tumor itself depending on the location and related to the treatment. Strabismus.
- Symptoms related to increased pressure in the brain often disappear after surgical removal of the tumor.
- Effects on coordination and balance improved and might progressively (to completely) disappear as recovery progresses.
- Steroid-treatment is often used to control tissue swelling that may occur pre- and post-operatively.
- Children Diagnosed can also suffer long term side effects due to the type of treatment they may receive.
Most treatments involve some combination of surgery and chemotherapy. Treatment with cisplatin, etoposide, and bleomycin has been described.
Before modern chemotherapy, this type of neoplasm was highly lethal, but the prognosis has significantly improved since.
When endodermal sinus tumors are treated promptly with surgery and chemotherapy, fatal outcomes are exceedingly rare.
The most common form of treatment is having the tumor surgically removed however total resection is often not possible. The location could prohibit access to the neoplasm and lead to incomplete or no resection at all. Removal of the tumor will generally allow functional survival for many years. In particular for pilocytic astrocytomas (that are commonly indolent bodies that may permit normal neurologic function) surgeons may decide to monitor the neoplasm's evolution and postpone surgical intervention for some time. However, left unattended these tumors may eventually undergo neoplastic transformation.
If surgery is not possible, recommendations such as chemotherapy or radiation be suggested however side effects from these treatments can be extensive and long term.
Around 50% of the AT/RTs will transiently respond, but chemotherapy by itself is rarely curative. No standard treatment for AT/RT is known. Various chemotherapeutic agents have been used against AT/RTs, which are also used against other CNS tumors including cisplatinum, carboplatinum, cyclophosphamide, vincristine, and etoposide. Some chemotherapy regimens are listed below:
- CCG clinical trial CCG-9921 was activated in 1993 and published its results in 2005. The proposed treatments did not have different outcomes and were not an improvement on prior treatments. Geyer published a review of chemotherapy on 299 infants with CNS tumors that evaluated response rate, event-free survival (EFS), and toxicity of two chemotherapeutic regimens for treatment of children younger than 36 months with malignant brain tumors. Patients were randomly assigned to one of two regimens of induction chemotherapy (vincristine, cisplatin, cyclophosphamide, and etoposide v vincristine, carboplatin, ifosfamide, and etoposide). Intensified induction chemotherapy resulted in a high response rate of malignant brain tumors in infants. Survival was comparable to that of previous studies, and most patients who survived did not receive radiation therapy.
- Sarcoma protocols. There has been at least one report in the literature of malignant rhabdoid tumors of the CNS being treated in as a high-grade intracranial sarcoma. These three cases were treated with surgery, chemotherapy, radiotherapy and triple intrathecal chemotherapy similar to the Intergroup Rhabdomyosarcoma Study III guidelines.
- Intrathecal protocols. One of the difficulties with brain and spinal tumors is that the blood brain barrier needs to be crossed so that the drug can get to the tumor. One mechanism to deliver the drug is through a device called an Ommaya reservoir. This is a device which shares some characteristics with a shunt in which a tube a surgically placed in the fluid surrounding the brain and a bulb shaped reservoir attached to the tubing is placed under the skin of the scalp. When the child is to receive intrathecal chemotherapy, the drug is administered into this bulb reservoir. At other times intrathecal chemotherapeutic agents are delivered through a lumbar puncture (spinal tap). A current Pediatric Brain Tumor Consortium Protocol uses intrathecal mafosfamide, a pre-activated cyclophosphamide derivative, in addition to other modalities to try to effect this tumor.
- High dose chemotherapy with stem cell rescue. This therapy uses chemotherapy at doses high enough to completely suppress the bone marrow. Prior to instituting this therapy, the child has a central line placed and stem cells are gathered. After therapy these cells are given back to the child to regrow the bone marrow. Stem cell rescue or autologous bone marrow transplantation, was initially thought to be of benefit to a wide group of patients, but has declined over the history of chemotherapy protocols.
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.
Medulloepithelioma carries a dismal prognosis with a median survival of 5 months.
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 traditional practice for childhood brain tumors has been to use chemotherapy and to defer radiation therapy until a child is older than three years. This strategy is based upon observations that children under three have significant long-term complications as a result of brain irradiation. However, the long-term outcomes of AT/RT are so poor that some protocols call for upfront radiation therapy, often in spite of young age.
The dose and volume of radiation had not been standardized, but radiation does appear to improve survival. The use of radiation has been limited in children younger than three because of the risk of severe neurocognitive deficits. Protocols using conformal, local radiation in the young child are used to try to cure this tumor.
External beam (conformal) radiation uses several beams that intersect at the tumor location; the normal brain tissue receives less radiation and cognitive function is thereby less affected.
Proton beam radiation was only offered at Massachusetts General Hospital in Boston and at Loma Linda, California, as of 2002. Since 2003, three or four more proton therapy centers have opened in the United States. St. Jude Children's Research Hospital is in the process of building one at their Memphis, Tennessee, location. Some centers have since opened in Europe. (Germany, Switzerland, and France).
Germinomas, like several other types of germ cell tumor, are sensitive to both chemotherapy and radiotherapy. For this reason, treatment with these methods can offer excellent chances of longterm survival, even cure.
Although chemotherapy can shrink germinomas, it is not generally recommended alone unless there are contraindications to radiation. In a study in the early 1990s, carboplatinum, etoposide and bleomycin were given to 45 germinoma patients, and about half the patients relapsed. Most of these relapsed patients were then recovered with radiation or additional chemotherapy.
Treatment of rhabdomyosarcoma is a multidisciplinary practice involving the use of surgery, chemotherapy, radiation, and possibly immunotherapy. Surgery is generally the first step in a combined therapeutic approach. Resectability varies depending on tumor site, and RMS often presents in sites that don't allow for full surgical resection without significant morbidity and loss of function. Less than 20% of RMS tumors are fully resected with negative margins. Fortunately, rhabdomyosarcomas are highly chemosensitive, with approximately 80% of cases responding to chemotherapy. In fact, multi-agent chemotherapy is indicated for all patients with rhabdomyosarcoma. Before the use of adjuvant and neoadjuvant therapy involving chemotherapeutic agents, treatment solely by surgical means had a survival rate of <20%. Modern survival rates with adjuvant therapy are approximately 60–70%.
There are two main methods of chemotherapy treatment for RMS. There is the VAC regimen, consisting of vincristin, actinomyocin D, and cyclophosphamide, and the IVA regimen, consisting of ifosfamide, vincristin, and actinomyocin D. These drugs are administered in 9–15 cycles depending on the staging of the disease and other therapies used. Other drug and therapy combinations may also show additional benefit. Addition of doxorubicin and cisplatin to the VAC regimen was shown to increase survival rates of patients with alveolar-type, early-stage RMS in IRS study III, and this same addition improved survival rates and doubled bladder salvage rates in patients with stage III RMS of the bladder.
Radiation therapy, which kill cancer cells with focused doses of radiation, is often indicated in the treatment of rhabdomyosarcoma, and the exclusion of this treatment from disease management has been shown to increase recurrence rates. Radiation therapy is used when resecting the entirety of the tumor would involve disfigurement or loss of important organs (eye, bladder, etc.). Generally, in any case where a lack of complete resection is suspected, radiation therapy is indicated. Administration is usually following 6–12 weeks of chemotherapy if tumor cells are still present. The exception to this schedule is the presence of parameningeal tumors that have invaded the brain, spinal cord, or skull. In these cases radiation treatment is started immediately. In some cases, special radiation treatment may be required. Brachytherapy, or the placement of small, radioactive “seeds” directly inside the tumor or cancer site, is often indicated in children with tumors of sensitive areas such as the testicles, bladder, or vagina. This reduces scattering and the degree of late toxicity following dosing. Radiation therapy is more often indicated in higher stage classifications.
Immunotherapy is a more recent treatment modality that is still in development. This method involves recruiting and training the patient's immune system to target the cancer cells. This can be accomplished through administering small molecules designed to pull immune cells towards the tumors, taking immune cells pulled from the patient and training to attack tumors through presentation with tumor antigen, or other experimental methods. A specific example here would be presenting some of the patient's dendritic cells, which direct the immune system to foreign cells, with the PAX3-FKHR fusion protein in order to focus the patient's immune system to the malignant RMS cells. All cancers, including rhabdomyosarcoma, could potentially benefit from this new, immune-based approach.
For malignant teratomas, usually, surgery is followed by chemotherapy.
Teratomas that are in surgically inaccessible locations, or are very complex, or are likely to be malignant (due to late discovery and/or treatment) sometimes are treated first with chemotherapy.
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.
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 treatment of choice is complete surgical removal ("i.e.," complete resection). Teratomas are normally well-encapsulated and non-invasive of surrounding tissues, hence they are relatively easy to resect from surrounding tissues. Exceptions include teratomas in the brain, and very large, complex teratomas that have pushed into and become interlaced with adjacent muscles and other structures.
Prevention of recurrence does not require "en bloc" resection of surrounding tissues.
Chemotherapy regimens for pediatric ependymomas have produced only modest benefit and degree of resection remains the most conspicuous factor in recurrence and survival.
The association of "TERT" expression with poor outcome in pediatric ependymomas has driven some researchers to suggest that telomerase inhibition may be an effective adjuvant therapy for pediatric ependymomas. Further, data from "in vitro" experiments using primary tumor isolate cells suggest that inhibition of telomerase activity may inhibit cell proliferation and increase sensitivity of cells to DNA damaging agents, consistent with the observation of high telomerase activity in primary tumors. Additionally, because apurinic/apyrimidinic endonuclease ("APE1") has been found to confer radiation resistance in pediatric ependymomas, it has been suggested that inhibitors of Ap endo activity might also restore radiation sensitivity.
Within the infratentorial group of pediatric ependymomas, radiotherapy was found to significantly increase 5-year survival. However, a retrospective review of sterotactic radiosurgery showed it provided only a modest benefit to patients who had previously undergone resection and radiation. Though other supratentorial tumors tend to have a better prognosis, supratentorial anaplastic ependymomas are the most aggressive ependymoma and neither total excision nor postoperative irradiation was found to be effective in preventing early recurrence.
Following resection of infratentorial ependymomas, residual tumor is more likely in lateral versus medial tumors, classified radiologically pre-operatively. Specific techniques, such as cerebellomedullary fissure dissection have been proposed to aid in complete resection while avoiding iatrogenic effects in these cases. Surveillance neuroimaging for recurrence provides additional survival to patients over observation alone.
hTERT and yH2AX are crucial markers for prognosis and response to therapy. High hTERT and low yH2AX expression is associated with poor response to therapy. Patients with both high or low expression of these markers make up the moderate response groups.
Treatment to remove these tumors always involve radical surgery. The reported recurrence rate for a subtotal removal is 30% after a mean interval period of 8.1 years.
Surgery is the primary treatment for removal of the brain tumor. Use of an endoscope may assist on obtaining a more complete surgical removal.
It has been seen that a few patients have tumors that grow unusually fast, especially after surgery. After surgery it is highly suggested the patients get quarterly MRI's to monitor their tumors or as per neurosurgeons/neurologists order. If monitoring the tumor, it is suggested to use the same facility for each scan. Using different facilities can result in minor variations in the scan which can result in false measurements of the brain tumor.
Intracranial epidermoid tumors are slow growing lesions, which may recur after incomplete removal during surgery, although it will most likely take many years. These slow growing benign brain tumors envelop nerves and arteries rather than displacing them.
Wide, radical, complete surgical excision is the treatment of choice, with free surgical margins to achieve the best outcome and lowest chance of recurrence. Radiation is only used for palliation. In general, there is a good prognosis, although approximately 50% of patients die from disease within 3–10 years of presentation.
Determination of treatment options depends on certain factors, some of which affect internal organs and others that affect personal appearance. When determining treatment, oncologists consider the initial location the tumor, the likelihood of body function deterioration, the effect on appearance, and the patient's potential response to chemotherapy and radiation. Surgery is the least successful of the treatment options; the tumor cannot be completely removed because it develops within the cells. Chemotherapy follows surgery to shrink or eliminate the remaining cancer cells.
Stem cell research under clinical trial shows promise to replace lost cells.
The aggressiveness of this cancer requires the response of a large team of specialists, possibly including a pediatric surgeon, oncologist, hematologist, specialty nurse, and rehabilitation specialists. Social workers and psychologists aid recovery by building a system of emotional support. Treatment is harsh on the body and may result in side effects including mood swings, learning difficulties, memory loss, physical deformations or restrictions, and potential risk of secondary cancers.
The objective of irradiation is to halt the growth of the acoustic neuroma tumour, it does not excise it from the body, as the term 'radiosurgery' or 'gammaknife' implies. Radiosurgery is only suitable for small to medum size tumors.