Spinal hemangioblastoma (HBL) is a slow-growing, highly vascularized tumor, accounting for 2 to 15% of primary spinal cord malignancies. It can arise as an isolated lesion or in association with Von Hippel-Lindau (VHL) syndrome (in 20-30% of the cases), presenting with multiple tumors spread throughout the central nervous system [1]. Clinically, mass effect, syringomyelia, or intramedullary hemorrhage, although exceedingly rare, may cause neurological deficits [2].
A 32-year-old woman presented with chronic headaches and sudden onset of numbness in the upper extremities (Mc Cormick grade II). A cervical MRI showed an oval mass in the intradural space at the obex extending to the superior margin of C2. The lesion exhibited avid contrast enhancement and was associated with idrosyringomyelia from the obex to C5 (Figure 1). The patient underwent suboccipital craniectomy, C1 laminectomy, and total removal of the intra-extramedullary mass. Intraoperatively, the lesion appeared red in color with tense-elastic consistency, richly vascularized, and closely located to the central canal of the spinal cord.
The postoperative course was unremarkable, and the patient was discharged seven days following surgery without focal deficits (Mc Cormick grade I). Postoperative MRI demonstrated total removal of the tumor with reduction of the syrinx. At six months follow up, the neurological status of the patient was normal without focal neurological deficits or signs of recurrence as demonstrated on MRI.
Pathological examination confirmed the diagnosis of a capillary HBL, showing groups of large polygonal, lipid-laden stromal cells, interspersed with thin-walled, closely packed blood-filled channels or vessels. Immunohistochemical staining revealed the presence of stromal cells positive for inhibin A and NSE while immunonegative for CD10 and EMA.
Typically, the radiological examination is required to define the location and characteristics of spinal HBLs. MRI remains the gold standard, with T1-weighted imaging showing bright, hyperintense signal and T2-weighted imaging that serves a crucial role in defining the boundaries of the lesion, along with the ability to identify any concurrent oedema or syringomyelia [1]. Small miliary lesions can be detected with the administration of gadolinium [3]. Based on the radiological findings, this tumor can be divided into three categories: intramedullary, extramedullary, or both.
The most common symptom at presentation, especially for HBLs located in the neck, occipital region, and shoulders, is a subtle radicular pain, which can be an early signal of sensory or motor dysfunction. Progressive worsening of the symptoms, including numbness of the lower or upper extremities and bladder/blower dysfunction, is associated with tumor progression, mass effect, or syringomyelia [1,2,4].
The most effective and definitive treatment for this rare entity is represented by microsurgical resection, which should only be carried out if neurological deficits are present. Intraoperative indocyanine green angiography may be used to verify complete tumor removal or to identify residual tumor. In cases where HBL presents with syringomyelia, it is not recommended to fenestrate, as a regression of the syrinx following tumor resection is frequently observed [2].
Gamma-knife radiosurgery has been used to treat some patients with multiple lesions but there is still no solid evidence to recommend such treatment [2,4].
Two valuable procedures to reduce surgery-related risks are electrophysiological monitoring, useful to avoid neurological damage during surgery, such as spinal cord or nerve injury [4], and percutaneous embolization, to reduce the risk of bleeding. Nonetheless, evidence shows that the latter increases the chances of intradural hemorrhage and neurological deterioration, therefore making it controversial and only advisable in patients with large tumors (>15mm) or adjacent tissue and bone invasion. Other factors that need to be acknowledged when considering preoperative embolization are the location of the tumor, its gross vascular anatomy, and the selection of the embolic materials [4,5].
Factors associated with deterioration seem to be the removal of multiple lesions, their location, and the concomitant presence of VHL syndrome. Total removal of the tumor is crucial since recurrence is frequently seen after partial resections. [2,3]