To determine and implement optimum management, treatment is often guided by a multidisciplinary team of cancer specialists who have experience treating childhood brain tumors.
In infants and young children, low-grade astrocytomas presenting in the hypothalamus may result in the diencephalic syndrome, which is manifested by failure to thrive in an emaciated, seemingly euphoric child. Such children may have little in the way of other neurologic findings, but can have macrocephaly, intermittent lethargy, and visual impairment. Because the location of these tumors makes a surgical approach difficult, biopsies are not always done. This is especially true in patients with neurofibromatosis type 1 (NF1). When associated with NF1, tumors may be of multifocal origin.
For children with low-grade optic pathway astrocytomas, treatment options should be considered not only to improve survival but also to stabilize visual function. Children with isolated optic nerve tumors have a better prognosis than those with lesions that involve the chiasm or that extend along the visual pathway.[1,2,4,5]; [Level of evidence: 3iiC] Children with NF1 also have a better prognosis, especially when the tumor is found in asymptomatic patients at the time of screening.[4,7] Observation is an option for patients with NF1 or nonprogressive masses.[1,4,8,9] Spontaneous regressions of optic pathway gliomas have been reported in children with and without NF1.[10,11,12]
Surgical resection is the primary treatment for childhood low-grade astrocytoma [1,2,4] and surgical feasibility is determined by tumor location. For example, complete or near complete removal can be obtained in 90% to 95% of patients with pilocytic tumors that occur in the cerebellum. Similarly, circumscribed, grade I hemispheric tumors are often amenable to complete surgical resection.[13,14] For children with isolated optic nerve lesions and progressive symptoms, complete surgical resection or local radiation therapy may result in prolonged progression-free survival. Diffuse astrocytomas may be less amenable to total resection, and this may account for the poorer outcome. The extent of resection necessary for cure is unknown because patients with microscopic and even gross residual tumor after surgery may experience long-term progression-free survival without postoperative therapy.[2,8] The long-term functional outcome of cerebellar pilocytic astrocytomas is relatively favorable. Full-scale mean IQs of patients with low-grade gliomas treated with surgery alone are close to the normative population. However, long-term medical, psychological, and educational deficits may be present in patients treated with surgery alone.[16,17][Level of evidence: 3iiiC]
Low-grade astrocytomas that occur in midline structures (e.g., hypothalamus, thalamus, brain stem, and spinal cord) can also be aggressively resected, with resultant long-term disease control;[10,11,18]; [Level of evidence: 3iiiA] however, such resection may result in significant neurologic sequelae, especially in children younger than 2 years at diagnosis.; [Level of evidence: 3iC] Because of the infiltrative nature of some deep-seated lesions, extensive surgical resection may not be appropriate and biopsy only should be considered.[Level of evidence: 3iiiDiii] Treatment options for patients with incompletely resected tumor must be individualized and may include observation, a second resection, chemotherapy, and/or radiation. A shunt or other cerebrospinal fluid diversion procedure may be needed.