Brain tumor
Table:
Brain tumor
Other names	Intracranial neoplasm, brain tumour

Brain metastasis in the right cerebral hemisphere from lung cancer, shown on magnetic resonance imaging
Specialty	Neurosurgery, oncology
Symptoms	Vary depending on the part of the brain involved, headaches, seizures, problem with vision, vomiting, mental changes[1][2]
Types	Malignant, benign[2]
Causes	Usually unknown[2]
Risk factors	Neurofibromatosis, exposure to vinyl chloride, Epstein–Barr virus, ionizing radiation[1][2][3]
Diagnostic method	Computed tomography, magnetic resonance imaging, tissue biopsy[1][2]
Treatment	Surgery, radiation therapy, chemotherapy[1]
Medication	Anticonvulsants, dexamethasone, furosemide[1]
Prognosis	Average five-year survival rate 33% (US)[4]
Frequency	1.2 million nervous system cancers (2015)[5]
Deaths	229,000 (2015)[6]

From the table, decide if the statement is entailed, neutral, or refuted by the data. Return the result as JSON: {"answer": "YOUR ANSWER"}.

Assertion: The prognosis for brain tumors has gotten better over the years.

answer: neutral