Hemangioblastoma in the medulla oblongata

A 80-year-old man presented with paresthesia in the upper and lower limbs, unstable gait, dizziness and lightheadedness.

MRI of the brain and cervical spine revealed an intra-axial space-occupying lesion in the posterior medulla oblongata, just below the level of the cerebellar tonsils (Figure 1-6). The lesion was of heterogeneous high signal on T2-weighted images (WI) (Figure 1,2 & 6). There was accompanying central oedema in the cervical spinal cord (Figure 1 & 2). After administration of gadolinium contrast, there was heterogeneous contrast enhancement of the lesion (Figure 4 & 5). There was a small intralesional cystic component (Figure 6). Biopsy and subsequent pathological examination were performed (Figure 7).

Hemangioblastomas are highly vascularized tumours of undefined origin, consisting of a dense capillary network separated by stromal cells which are frequently associated with cysts. They account for 1-2% of all intracranial tumours. Most hemangioblastomas occur in the posterior fossa (85%), with the cerebellum being most common (65%) and approximately 20% within the brainstem. 15% occur in the spinal cord. Supratentorial hemangioblastoma is very rare. The lesion does not metastasize [1,2].

The mean age is 48 years [3]. Approximately 70-80% of all hemangioblastomas are sporadic [4]. Approximately 10–30% of patients with hemangioblastoma are associated with Von Hippel Lindau (VHL) syndrome, an autosomal dominant disorder caused by a deletion in chromosome 3 (3p). Typically, these patients have multiple hemangioblastomas and/or visceral abnormalities such as retinal angiomas, pancreatic or renal cysts, renal cell carcinoma, pheochromocytoma, and polycythemia, among others [2].

Spinal hemangioblastomas are often intramedullary located and typically occur in the dorsal part of the cord at the midline. Mixed intramedullary and extramedullary location is seen in 10-15 %. Involvement of the thoracic spine is slightly more common than cervical region.

Patients present with slowly progressive radicular symptoms and long tract findings. Alterations in sensation are most common, with deficits in proprioception due to involvement of the dorsal columns [2].

Imaging may suggest the diagnosis in case of expansile intra-axial infratentorial brain or spinal cord lesions with cystic and solid enhancing components.   These cysts can be of variable intensity on T1- and T2-WI, depending on the protein content. Hemangioblastomas are often associated with significant oedema. Less frequently serpiginous flow voids are present indicating vessels. Contrast-enhanced images demonstrate marked enhancement of the vascular nodular components, whereas cystic components do not enhance [5].

The differential diagnosis includes metastasis, ependymoma, astrocytoma and glioblastoma. Astrocytoma is typically seen in a pediatric population, whereas ependymoma typically affects adults.

Histology is mandatory for final diagnosis.

Management options, clinical outcome and prognostic factors have not yet been fully elucidated [6]. The preferred treatment option is surgery. Preoperative embolization can be performed to reduce bleeding. Tumour treatment with radiosurgery serves as an adjunct therapy [7]. The patient was treated with radiotherapy only, due to his age and the potential risks of neurosurgery.

In conclusion, sporadic hemangioblastoma should be considered in case of an intra-axial with cystic and enhancing vascular components, even in older patients. Intralesional cyst can be subtle like our case.

Written informed patient consent for publication has been obtained.