A 2-year-old boy was admitted with a one-month history of headache and nausea. The physical examination was unremarkable except for papilloedema. The patient was referred for cranial magnetic resonance imaging (MRI).
Cranial MRI revealed pan-ventricular hydrocephalus and a solid mass located within the trigone of the left lateral ventricle. The lesion showed a lobular contour and had the size of 21x27x31 mm. On T1-weighted images, it was isointense compared to white matter and hyperintense on T2-weighted images. It enhanced vividly following intravenous gadolinium injection and had no diffusion restriction. The temperoparietal white matter adjacent to the lesion showed vasogenic oedema that was considered to be an invasion. The signal characteristics, contrast enhancement pattern, localization of the lesion, invasion of white matter, and hydrocephalus helped make the initial diagnosis of choroid plexus carcinoma. The patient underwent total excision of the lesion and the diagnosis of choroid plexus carcinoma was confirmed histopathologically. No drop metastases were identified on spinal MRI. The hydrocephalus did not improve following surgery, and a ventriculoperitoneal shunt was consequently inserted. Subsequently, adjuvant chemotherapy was initiated.
Choroid plexus carcinoma is a rare intraventricular tumour arising from the choroid plexus epithelium and constituting 0.2-0.4% of childhood brain tumours . It is encountered often in childhood between 1-3 years of age . The most common location is the trigone of the lateral ventricles. The patients presented with hydrocephalus and symptoms suggestive of raised intracranial pressure. Hydrocephalus may occur due to either spread of the tumour or overproduction of cerebrospinal fluid (CSF) . The localisation within the trigone of the lateral ventricle, the lobular contour, and intensive contrast enhancement are common features of both choroid plexus papilloma and carcinoma, and it is not always possible to differentiate radiologically. Large size, heterogeneous mass owing to haemorrhage and/or necrosis and invasion of adjacent brain parenchyma favour choroid plexus carcinoma . The treatment consists of surgical resection, chemotherapy, and radiotherapy for patients over 3 years of age. Although the survival rate is closely related to total resection of the tumour, invasion of the surrounding brain tissue and large size of the lesion may interfere with the possibility of total resection . Since the tumour spreads through the CSF, contrast-enhanced spinal MRI should be performed at the time of diagnosis and during follow-up.
Differential Diagnosis List
Choroid plexus carcinoma
Choroid plexus papilloma
Other intraventricular paediatric tumours as ependymoma