Clinical scenario:
An 8-year-old boy presents with a 3-month history of progressive headache, early morning vomiting, and decline in school performance. Over the last 2 weeks, he has developed right-sided weakness and focal seizures involving the right upper limb. On examination, he has papilledema and mild right hemiparesis. MRI brain reveals a large, irregular ring-enhancing lesion in the left frontal lobe with extensive surrounding edema and significant mass effect. There is no fever, and routine blood investigations are unremarkable.
What is the most likely diagnosis?
A. Brain abscess
B. Dysembryoplastic neuroepithelial tumor (DNET)
C. Glioblastoma multiforme
D. Pilocytic astrocytoma
E. Tuberculoma
Correct answer & Explanation:
Correct answer: C. Glioblastoma multiform
Discussion: Glioblastoma multiform
This child has features of a high-grade supratentorial space-occupying lesion (SOL):
Progressive symptoms of raised intracranial pressure
Focal seizures
Contralateral hemiparesis
MRI showing an irregular ring-enhancing lesion with extensive vasogenic edema and mass effect
Although uncommon in children compared with adults, glioblastoma multiforme (WHO Grade 4 diffuse pediatric-type high-grade glioma) is the most likely diagnosis. High-grade gliomas characteristically demonstrate:
Heterogeneous or ring enhancement
Central necrosis
Extensive perilesional edema
Rapid clinical progression
Why the Other Options Are Incorrect
A. Brain abscess
May produce ring enhancement but is usually associated with fever, elevated inflammatory markers, congenital heart disease, sinusitis, or otitis.
Clinical course is generally shorter.
B. Dysembryoplastic neuroepithelial tumor (DNET)
Typically presents with long-standing epilepsy.
Usually a cortical lesion with minimal mass effect and little surrounding edema.
D. Pilocytic astrocytoma
Most commonly arises in the cerebellum.
Usually a cystic lesion with an enhancing mural nodule rather than an irregular necrotic ring-enhancing mass.
E. Tuberculoma
Can present as an SOL with seizures, especially in endemic regions.
Often demonstrates conglomerate ring lesions, may have evidence of systemic tuberculosis, and generally progresses more slowly. Extensive edema can occur, but a solitary irregular necrotic frontal lesion with rapid neurological deterioration is more suggestive of a high-grade glioma.
Key Postgraduate Pearl
In a child with a solitary supratentorial ring-enhancing lesion, the major differential diagnoses are:
High-grade glioma
Brain abscess
Tuberculoma
Metastasis (rare)
Tumefactive demyelination
Extensive vasogenic edema, central necrosis, irregular thick ring enhancement, and rapid progression strongly favor a high-grade glioma such as glioblastoma.e
