Central Nervous System Tumors in Children

Tumors of the central nervous system (CNS) affect the brain and spinal cord and are the second most prevalent pediatric cancer after acute lymphoblastic leukemia (20% of pediatric malignancies). Each year, around 2,000 children and adolescents are diagnosed with brain tumors. The male gender predominates in childhood, with the peak incidence occurring during the first decade of life. Cerebellar tumors are more prevalent in children aged 1 to 2, although cerebral tumors prevail in older children.

Etiology of CNS Tumors

CNS tumors are more common in hereditary diseases such as neurofibromatosis types 1 and 2, von Hippel-Lindau, tuberous sclerosis, and Li-Fraumeni syndrome. However, one of these syndromes will affect less than 10% of children with brain tumors. Ionizing radiation exposure has also been linked to the development of CNS tumors. Following solid organ transplantation, CNS lymphoma is more common in people with immune suppression disorders (Wiskott-Aldrich syndrome, ataxia-telangiectasia, and acquired immunodeficiency syndrome). However, most children with brain tumors have no known etiology.

Psychological Issues in Children

Compared to other pediatric malignancies, such as leukemia, psychological investigations of pediatric CNS tumors were uncommon until recently. Recent research on the neuropsychological functioning of children with CNS tumors has discovered that they are at risk for severe and irreversible neurocognitive impairments. Cranial radiation (particularly whole brain or supratentorial), young age (less than four years old), extended duration from treatment, tumor location, and presence of hydrocephalus are all risk factors.

Expected consequences include substantial issues with attention, memory, processing speed, arithmetic ability, and lower IQ and sensory deficiencies; these children are typically put in special education programs. When youngsters attempt to do things that they have previously mastered, they might grow frustrated and despondent. Children with slower processing speeds and abilities may be less able to understand or respond to social cues, resulting in less social contact.

Children may be perceived as different and have more trouble with peer acceptance and socialization because of their changed looks, some of which may be permanent (e.g., baldness from radiation, surgical scars or malformed head, small height, decreased emotional expressiveness). They may also grow more solitary as they avoid rejection from peers.

In addition to one-on-one cognitive/behavioral treatment and counseling to assist families dealing with CNS tumor sequelae, social skills interventions and involvement in oncology-related organizations and camps may be effective. Children with CNS tumors should be examined longitudinally for at least five years following diagnosis, and relevant school interventions should be implemented.

Acute Management

The children suspected with brain tumor may require immediate medical attention. Those with unstable vital signs changed mental state, or concerns about increasing ICP require prompt examination, which is best handled in the emergency room. Although magnetic resonance imaging (MRI) with and without contrast is the gold standard imaging technique for excellent visualization of brain tumors and is frequently required for neurosurgical planning, a computed tomographic (CT) scan may be the best initial imaging decision in the unstable youngster.

CT scans can detect acute hydrocephalus, imminent herniation, or acute hemorrhage, all of which are neurosurgical emergencies. They can also indicate the anatomical location of a mass, the extent of the lesion, hydrocephalus, and if the tumor is squeezing other brain structures, assisting in triaging and planning a timetable for MRI, surgery, or other sedated operations.

When deciding on the best initial imaging study for a young child who would require anesthesia to complete an MRI, the relative risks of anesthesia versus the risk of exposure to ionizing radiation from a CT scan, which could be completed without sedation, must be considered, as well as the degree of suspicion for an abnormality and individual risk factors specific to that patient.

MRI with and without contrast is the most often used imaging modality for brain tumor diagnosis and monitoring. With more specialized sequences for visualization of edema, connection to CNs, blood arteries, and perfusion, MRI enables a more thorough characterization of the tumor and the surrounding anatomy.

Emergency Care

Treatment for high intracranial pressure must begin as soon as a CNS tumor is detected, in tandem with diagnostic measures. The patient should not lay flat, and dexamethasone (initially 1 mg/kg to a maximum of 50 mg; subsequently 0.5 to 1.5 mg/kg/day; from the third to fifth day, or when the cerebral pressure crisis is past, 0.15 mg/day; afterward taper depending on the clinical status) should be supplied.

Patients who are on mechanical ventilation should be hyperventilated. Head rotation should be avoided (jugular drainage). External CSF draining is used as a stopgap therapy until the tumor can be surgically removed. Early excision is recommended if the risk is manageable and near-total tumor eradication is possible without significant neurological impairment.

Steroids are the preferred therapy for spinal masses. Neurosurgery is necessary in the case of medullary compression, particularly in previously irradiated parts of the spinal column, radio- and chemoresistant tumors, and tumors characterized by biopsy. Laminectomy and fixation are surgical treatments. Radiotherapy is also suggested for palliation in radiosensitive tumors due to the potentially catastrophic neurological repercussions (quadriplegia!) and extreme pain.

Seizures are frequently the initial symptom in teenagers and supratentorial tumors (1% to 6% in infratentorial tumors). Childhood mortality rates range from 3% to 5%. The treatment consists of general measures (airways! oxygen, i.v. access, and so on) and antiepileptics.

Treatment

CNS tumor treatment includes a variety of disciplines and techniques. Magnetic resonance imaging (MRI) is typically performed before surgery to determine the location and size of the tumor. Surgery, whether for a biopsy or attempted resection (removal), is typically the initial step in treatment. For most tumors, excision or at least gross complete resection is associated with a better prognosis (however, the more thorough the operation, the higher the risk of morbidity).

A fraction of patients receives radiation treatment (varying from 35 to 54 Gy), chemotherapy, or a combination. Because of their location (such as brainstem or optic tract tumors), many patients may get radiation, chemotherapy, or both. The particular therapy for the more frequent CNS tumors is given below.

Surgery, craniospinal radiation treatment, and chemotherapy (drugs such as cisplatin, vincristine, CCNU, and Cytoxan) are used to treat medulloblastomas and primitive neuroectodermal tumors (PNETs). Low-grade astrocytomas are treated with surgery alone, localized radiation treatment or surgery combined with chemotherapy (the most often used drugs are carboplatin and vincristine). Surgery, radiation treatment, and chemotherapy (drugs such as prednisone, CCNU, vincristine, procarbazine, and carboplatin) are used to treat high-grade gliomas.

This category of tumors is also treated with high-dose chemotherapy combined with stem cell rescue. The most common treatments for ependymomas are surgical excision and radiation therapy. Cisplatin, a chemotherapeutic drug, shows some activity in these tumors. Radiation treatment is used to treat brainstem gliomas. Several chemotherapeutic regimens have been explored, but none have increased survival compared to radiation treatment alone.

Conclusion

Tumors of the central nervous system (CNS) are the second most prevalent pediatric cancer, with male gender predominance and peak incidence occurring during the first decade of life. The etiology of CNS tumors is unknown, and presentation is determined by location, age, and developmental level. Prognosis varies due to a variety of tumor types and sites.

Brain tumors outlive all other pediatric cancers in terms of fatality. Children with CNS tumors risk severe and irreversible neurocognitive impairments due to radiation, age, location, and hydrocephalus. Psychological interventions and school interventions should be implemented.