Supratentorial PNETs most often present with clinical features of elevated ICP. Intracranial hypertension may be related to the mass of the tumor or to obstructive hydrocephalus.
- Infants – large head and vomiting: In infants symptoms of elevated ICP may include vomiting, accelerated head growth, a bulging anterior fontanel, lethargy, papilledema, and abducens nerve palsy.
- Children – headache and altered mental status: In older children, elevated ICP can manifest as headache, nausea, vomiting, mental status change, papilledema, and abducens nerve palsy.
Patterns of evolution
As with other mass lesions of the CNS, the clinical presentation of supratentorial PNETs depends on the location of the mass and the regional neuroanatomy that is affected.
- Weakness and sensory disturbances: Cerebral supratentorial PNETs typically grow from within the deep white matter and can involve corticospinal fibers and/or sensory fibers. As such, patients may present with contralateral weakness and/or sensory disturbances.
- Seizures: Cerebral supratentorial PNETs may involve the cortex of the brain and cause seizures.
- Endocrine and visual disturbances: Suprasellar supratentorial PNETs may compromise adjacent visual and neuroendocrine structures.
Time for evolution
- Less than 3 months: The duration of symptoms prior to diagnosis rarely exceeds 3 months, which is what one might expect with a rapidly growing tumor.
Evaluation at Presentation
- See EVALUATION
- Steroids in preparation for surgery: Most children present with signs of elevated ICP but are stable. The patient is typically started on dexamethasone and ranitidine, and preparations are made for surgical intervention.
Preparation for definitive intervention, nonemergent
- Dexamethasone plus ranitidine
- Routine preoperative preparation: Blood is cross-matched as appropriate depending on the size and location of the tumor. Routine blood work and coagulation studies are done. Importantly, there is an assessment by the anesthesiologist, especially in the very young child with a large tumor.
Preparation for definitive intervention, emergent
- Brain relaxation: Dexamethasone plus ranitidine IV and mannitol, 20 mg/kg IV rapidly.
- Cross-match blood.
- Either treatment of enlarged ventricles or removal of tumor: If the child presents with evidence of transtentorial herniation, emergency surgery is required. If the ventricles are enlarged, an EVD may be placed prior to definitive surgical resection of the tumor. If not, emergent tumor resection is undertaken.
- Same as for any other child needing treatment for a brain tumor.