Hemangioblastoma Workup

Updated: Sep 26, 2017
  • Author: Konstantin V Slavin, MD; Chief Editor: Brian H Kopell, MD  more...
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Approach Considerations

Perform blood tests to help reveal associated lesions that may be a part of the VHL disease complex. Unfortunately, finding polycythemia does not help in diagnosing the tumor.

The diagnostic workup of suspected hemangioblastomas must include, in addition to history, physical, and thorough neurologic examination, complete neural axis imaging and abdominal CT scan or ultrasound. The goal of these additional tests is to reveal associated lesions that may be a part of VHL disease complex.

Perform a detailed ophthalmologic evaluation to help reveal associated lesions that may be a part of the VHL disease complex.


Imaging Studies

Radiographically, hemangioblastomas are best diagnosed with MRI. [35] MRI of hemangioblastomas usually shows an enhancing mass clearly delineated from the surrounding brain or spinal cord tissue. The tumor tissue may be hypointense or isointense on precontrast T1-weighted images and hyperintense on T2-weighted images. [36, 37]

Plain radiographs usually do not aid in diagnosis. Myelography and cisternography, which were considered the tests of choice in the past, now are almost never used in the diagnostic workup of hemangioblastomas.

Plain computed tomography (CT) scan may reveal hypodensity of the tumoral cyst and associated hydrocephalus. CT scans with intravenous contrast show uniform enhancement of the tumor nodule that, in association with the adjacent cyst, may be extremely characteristic of posterior fossa hemangioblastomas.

Cerebral and spinal angiography reveals a highly vascular tumor blush, and this diagnostic modality may be extremely useful for assessing the vascular supply to the tumor. This information may help the surgeon during tumor resection.

In patients with hemangioblastomas, complete neural axis imaging usually is recommended to rule out multiple lesions, especially in those cases in which VHL syndrome is either diagnosed or clinically suspected.


Histologic Findings

Histologically, hemangioblastomas are vascular neoplasms. In addition to relatively normal-appearing endothelial cells that line capillary spaces, hemangioblastomas have 2 distinct cellular components that may occur in the same tumor in different proportions. The first type is small, perivascular, endothelial cells that have dark, compact nuclei and sparse cytoplasm. Cells of the second type contain multiple vacuoles and granular eosinophilic cytoplasm rich in lipids. These stromal cells may show some nuclear pleomorphism, but mitotic figures are rarely seen. The exact histogenetic origin of stromal cells is unknown, but studies indicate that they may represent a heterogeneous population of abnormally differentiating mesenchymal cells of angiogenic lineage, with some morphologic features of endothelium, pericytes, and smooth-muscle cells. [38]

Two histologic subtypes (cellular and reticular) have been described in primary hemangioblastomas of the central nervous system and have been found to correlate with the probability of tumor recurrence. [39] The reticular subtype is more commonly encountered; the cellular subtype is associated with higher probability of recurrence.

No histologic grading system exists for hemangioblastomas.