Glioma+(child)


 * **Epidemiolgy:** || Glioma covers a broad class of brain tumors which cover 80% of all childhood brain tumors.[6] This class can be divided into two main groups high and low grade where low grade encompasses the majority of diagnosed cases. Most often these tumors originate in the cerebellum but are not limited and are accompanied with symptoms of headache and nausea as well as unsteadiness in walking. ||
 * **Etiology:** || These tumors begin in the glia of the brain and spinal cord, an increased incidence of brainstem glioma has been observed consistently in patients with neurofibromatosis up to 14% in some reports.[1] No genetic or molecular markers have been recognized for brainstem gliomas. Although no familial tendency is prominent overall there are studies that show al link between radiation exposure and formation of gliomas after treatment of leukemia when EBRT has been used. [1] ||
 * **Signs & Symptoms:** || Children with a brain stem glioma may experience the following symptoms or signs[7]. Sometimes, children with a brain stem glioma do not show any of these symptoms[7]. Or, these symptoms may be caused by a medical condition that is not a brain stem glioma[7].

Double vision or not being able to close the eyelids

Drooping of the face

Difficulty chewing and swallowing food

Weakness in the arms and legs, clumsiness or wobbliness, and difficulty walking

Difficulty talking

Headache

Vomiting

The child’s doctor will ask you questions about the symptoms your child is experiencing to help find out the cause of the problem, called a diagnosis. This may include how long your child has been experiencing the symptom(s) and how often[7].

If a tumor is diagnosed, relieving symptoms and side effects remains an important part of care and treatment[7]. This may also be called symptom management, palliative care, or supportive care. Be sure to talk with the health care team about symptoms your child experiences, including any new symptoms or a change in symptoms[7]. || In addition to a physical examination, the following tests may be used to diagnose a brain stem glioma[7]:
 * **Diagnostic Procedures:** || Doctors use many tests to diagnose a brain stem glioma and find out if it has metastasized (spread)[7]. Some tests may also determine which treatments may be the most effective[7]. For most other types of tumors, a biopsy is the only way to make a definitive diagnosis[7]. However, biopsies are rarely used and are often specifically avoided in children with diffuse brain stem glioma because the results of the biopsy do not influence treatment, and it can have major risks. In addition, the diagnosis can often be made by magnetic resonance imaging (MRI) alone (see below). Because of this, diffuse brain stem glioma is unlike most other tumors. For a focal tumor, a biopsy and removing the tumor with surgery may be considered. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis. Other imaging tests may be used to find out whether the tumor has metastasized. Your child’s doctor may consider these factors when choosing a diagnostic test[7]:
 * Age and medical condition
 * Type of tumor suspected
 * Severity of symptoms
 * Previous test results

Computed tomography (CT or CAT) scan. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a contrast medium is injected into a vein to provide better detail. For a brain stem glioma, this test generally does not provide enough information to make a definite diagnosis, and an MRI is still needed[7].

|| The American Joint Committee on Cancer recommends the following guidelines for grading tumors: [8] **__GX:__** Grade cannot be assessed (Undetermined grade) __**G1:**__ Well-differentiated (Low grade) __**G2:**__ Moderately differentiated (Intermediate grade) __**G3:**__ Poorly differentiated (High grade) __**G4:**__ Undifferentiated (High grade) || The tumor can be classified as diffuse or focal. [9] || __** Seizures: **__ __** Visual problems: **__ __** Pituitary and hypothalamic dysfunction: **__ __** During infection, surgery, and illness, optic glioma survivors are very likely to need support with extra steroid medication: **__ __** Increased risk for cerebrovascular events (strokes): **__ __** Increased risk of second neoplasms: **__ __** Cranial RT more than 10 years old can be associated with scattered radiation to the thyroid. There is an increased risk of: **__ High-grade astrocytomas: prognosis is generally poor. [1] || Surgery is recommended for “exophytic” chiasmatic/hypothalamic tumors. Chemotherapy trials are being done for optic chiasm and hypothalamic gliomas. Radiation is highly effective for “exophytic” chiasmatic/hypothalamic tumors. Surgery with complete resection is recommended. No indication for radiation if the tumor is completely resected; however, should be given if incompletely resected. Surgery is treatment of choice and achievable in 80-90% of cases. Radiation is not clearly indicated. [2] Surgery is treatment of choice; however, it is very difficult to achieve a total resection. Chemotherapy has been supported by a CCG study. Radiation therapy is recommended post-operatively in children over 3-5 years old. Surgery and radiation therapy are the treatments of choice. || Brain: Whole 4500 cGy, 2/3 5000 cGy, 1/3 6000 cGy Ear (acute serous otitis: Whole 3000 cGy, 2/3 3000 cGy, 1/3 3000 cGy Ear (chronic serous otitis: Whole 5500 cGy, 2/3 5800 cGy, 1/3 6000 cGy Lens: Whole 1000 cGy Optic chiasm: Whole 5000 cGy Optic nerve: Whole 5000 cGy Retina: Whole 4500 cGy [3] || 2. Chao KS, Perez CA, Brady LW. //Radiation Oncology: Management Decisions.// Philadelphia, PA: Lippincott Williams & Wilkins; 2002. 3. RadiationOncology/Toxicity/Emami. Available at: []. Accessed June 25, 2012. 4. Lymphatic drainage of the brain and the pathophysiology of neurological disease. Available at: []. Accessed on June 26, 2012. 5. Washington CM, Leaver D. //Principles and Practice of Radiation Therapy//. St. Louis, MO: Mosby; 2010. 6. // Brain Cancer Overview //__ ,** [] ** __, Accessed June 28 2012. 7. Brain Stem Glioma-Children. May 18, 2012. Available at: []. Accessed on June 28, 2012. 8. Tumor grade. National Cancer Institute. Available at: []. Accessed on June 25, 2012. 9. Brain stem glioma- Childhood. American Society of Clinical Oncology. Available at: []. Accessed on June 25, 2012. 10. Optic pathway glioma. Pediatric Oncology Materials. Available at: []. Accessed on June 25, 2012. ||
 * **Histology:** || Astrocytomas originate from astrocytes which are part of the supportive tissue structure of the brain. [5] Low grade astrocytomas which include optic gliomas, grow slow and steady. High grade astrocytomas include most brainstem gliomas and grow rapidly acting malignant.[5] ||
 * **Lymph node drainage:** || There are no true lymphatic pathways from the brain.[4] ||
 * **Metastatic spread:** || Primary brain tumors very rarely spread outside of the cranial cavity and are more likely to invade other areas of the brain. Brain metastases are spread from other areas of the body to the brain and are not associated with a primary brain lesion. [6] ||
 * **Grading:** || Tumor grade is a system used to classify cancer cells by how abnormal they look under a microscope, and how quick the tumor can grow and spread. The specific factors that determine tumor grade vary with each type of cancer. [8]
 * **Staging:** || Tumor staging refers to the extent and severity of the cancer. [8] There is no formal staging for pediatric brain stem or optic nerve Glioma.
 * **Radiation side effects:** || Some of the late effects of Radiation Therapy (RT) on a Glioma (depending on the area of RT) are: [10]
 * __ Neurocognitive problems: __**
 * Poor short term memory
 * Difficulty with executive function
 * __ Depression: __**
 * Usually related to multiple long-term health problems and neurocognitive dysfunction
 * Side effect of scarring related to tumor and previous RT
 * Responds to anticonvulsant therapy
 * Can lead to optic atrophy, decreased vision and field defects
 * RT may damage the optic nerves and chiasm
 * RT can cause cataracts (lens of the eye is very sensitive to low dose RT)
 * RT can result in hypopituitarism
 * Increased risk of metabolic syndrome (with hypertension)
 * Blood pressure should be checked in any patient who has a history of cranial RT
 * GH deficiency (common with failure to grow)
 * Risk of TSH deficiency
 * Risk of LH/FSH deficiency
 * Risk of ACTH deficiency
 * They should be seen by an endocrinologist every year or so who will assess pituitary function and supervise replacement therapy
 * RT effect on cerebral vasculature
 * Significantly increased risk of TIA’s and cerebrovascular disease in these patients (especially those who have NF1)
 * RT induced Meningioma is common
 * RT induced malignancy is less common
 * Hypothyroidism
 * Thyroid cancer and multinodular goitre ||
 * **Prognosis:** || Low-grade astrocytomas: prognosis is favorable, especially when complete excision is possible. [1]
 * **Treatments:** || ** Low-grade diencephalic glioma (optic chiasmatic/ hypothalamic glioma/ low-grade thalamic glioma) **
 * For optic pathways and hypothalamic tumors – local treatment volumes
 * 3-D conformal or SRT techniques used for chiasm and/or hypothalamus
 * Optic pathways involving optic nerves or tracts use opposed laterals with high-energy photons.
 * Doses: 50Gy for >3 years of age, 45Gy for <3 years of age, 54Gy for thalamic gliomas. [2]
 * Low-grade cerebral hemeispheric gliomas **
 * Local treatment volumes; 3-D conformal or SRT techniques
 * Doses: 54-55Gy, 60Gy with SRT [2]
 * Cerebellar Astrocytomas **
 * Malignant gliomas (anaplastic astrocytoma, glioblastoma, anaplastic oligodendrogliomas, and malignant mixed glioma) **
 * Wide local volumes
 * Doses: 54-60Gy [2]
 * Brainstem glioma **
 * Radiation is primary for tumors arising in the pons, which require 2 to 3 cm margins.
 * Opposed laterals with high-energy photons
 * 3-D conformal or SRT
 * Doses: 72Gy with SRT and 50-55Gy with 3-D conformal [2]
 * **TD 5/5:** || Brainstem: Whole 5000 cGy, 2/3 5300 cGy, 1/3 6000 cGy
 * **References:** || 1. National Cancer Institute. Available at: []. Accessed June 25, 2012.

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