A hemangioblastoma is a slow-growing, noncancerous tumor that develops in the blood vessels of the central nervous system. These tumors are most commonly found in the cerebellum (the part of the brain that controls balance and coordination), but they can also appear in the brainstem, spinal cord, or retina. About 70% of cases occur randomly with no known cause, while the remaining 30% are linked to an inherited condition called Von Hippel-Lindau (VHL) disease.
Where Hemangioblastomas Grow
The cerebellum is the most common site, but hemangioblastomas can develop anywhere along the central nervous system. Each location produces different symptoms because different parts of the brain and spinal cord control different functions.
- Cerebellum and surrounding brain tissue: Headache, dizziness, nausea, vomiting, and difficulty with balance or coordination.
- Brainstem: Trouble swallowing, double vision or difficulty moving the eyes, slurred speech, facial weakness, and unsteady walking.
- Spinal cord: Neck or back pain, weakness, numbness or tingling in the limbs, and problems with bladder or bowel control.
- Retina: Blurry vision or vision loss.
Symptoms often develop gradually because these tumors grow slowly. In many cases, the tumor itself is small, but it creates a fluid-filled cyst around it that presses on nearby brain tissue. That pressure, rather than the tumor mass itself, is frequently what triggers symptoms.
What These Tumors Look Like on Imaging
On MRI, hemangioblastomas have a distinctive appearance that helps doctors identify them. About 60% of cases show up as a well-defined cyst with a small solid nodule (called a mural nodule) attached to the cyst wall. The cyst walls themselves don’t light up on contrast imaging, but the nodule enhances vividly because it’s packed with blood vessels. In 60 to 70% of cases, enlarged blood vessels around the cyst’s edges are visible as dark spots on certain MRI sequences, a clue to the tumor’s highly vascular nature.
The other 40% of hemangioblastomas are entirely solid with no cystic component. These solid tumors can be harder to distinguish from other brain tumors on imaging alone, though the intense contrast enhancement remains a hallmark. Doctors sometimes use specialized blood vessel imaging (angiography) to confirm the diagnosis before surgery, since the tumor’s rich blood supply is a key surgical consideration.
The Connection to Von Hippel-Lindau Disease
VHL disease is a genetic condition caused by a mutation in a tumor-suppressing gene on chromosome 3. People with VHL are predisposed to developing hemangioblastomas, often multiple tumors, and at younger ages than those with sporadic cases. VHL also raises the risk of tumors in the kidneys, adrenal glands, and pancreas, so a diagnosis of hemangioblastoma in a young person typically prompts genetic testing.
The distinction matters for long-term care. Someone with a single sporadic hemangioblastoma who has it fully removed may never need treatment again. A person with VHL, on the other hand, can develop new hemangioblastomas throughout their life and needs ongoing surveillance with regular MRI scans. About 30% of all hemangioblastoma patients fall into this hereditary category, making genetic screening an important step in the diagnostic process.
How Hemangioblastomas Are Treated
Surgery to completely remove the tumor is the primary treatment and is considered curative for isolated hemangioblastomas. When the tumor has a cystic component, the surgeon removes the solid nodule; the cyst itself typically resolves once the nodule is gone. Because these tumors are so rich in blood vessels, the surgery requires careful planning to minimize bleeding, and specialized imaging beforehand helps surgeons map the blood supply.
Stereotactic radiosurgery, a focused form of radiation delivered in one or a few sessions, is an alternative for tumors that are small, difficult to reach surgically, or in patients who aren’t good candidates for open surgery. In practice, the two approaches tend to be used for different situations rather than being direct competitors. Surgical patients in published series typically have larger, cystic tumors, while radiosurgery patients more often have smaller, solid tumors. For VHL patients with multiple tumors, doctors sometimes combine both strategies, operating on symptomatic or large tumors while monitoring or irradiating smaller ones.
Active surveillance with regular MRI is also a valid approach for small, asymptomatic tumors, particularly in VHL patients who may have several lesions that aren’t yet causing problems. Not every tumor needs immediate treatment.
A Newer Drug Option for VHL Patients
For people with VHL disease who have multiple or recurring hemangioblastomas, a medication called belzutifan offers a newer approach. This drug works by blocking a protein that drives abnormal blood vessel growth in VHL-related tumors. In case reports, patients have shown marked shrinkage of cerebellar tumors as early as two weeks after starting treatment, with continued improvement and stabilization over the following months. Visual improvements have also been observed in patients with retinal hemangioblastomas. This type of targeted therapy is particularly relevant for VHL patients who face repeated surgeries over their lifetime.
Recurrence and Long-Term Outlook
The overall prognosis after complete surgical removal is good. Recurrence rates generally stay below 25%, though the likelihood depends on several factors. The cellular structure of the tumor matters: one subtype (cellular) recurs about 25% of the time, while another (reticular) recurs only about 8% of the time. Patients with VHL disease, those diagnosed at a younger age, and those with multiple tumors face higher recurrence rates than people with a single sporadic hemangioblastoma.
When tumors do come back, both repeat surgery and repeat radiosurgery are effective options. Smaller recurrences (under about 1 cubic centimeter) can often be managed with radiosurgery alone, while larger recurrences may require a second operation. Long-term follow-up with regular neurological exams and imaging is standard for all patients, whether sporadic or VHL-associated, to catch any regrowth or new tumors early.