Is there a higher risk of intracranial aneurysms for those with a Pituitary adenoma?

An intracranial aneurysm is a bulging, weakened area in the wall of a blood vessel in the brain. If it ruptures, it can cause serious bleeding. People with pituitary adenomas (non-cancerous tumors of the pituitary gland) may wonder if they face a higher risk of having one of these aneurysms. Research suggests that the answer is yes: several studies have found that pituitary adenoma patients have a higher prevalence of intracranial aneurysms compared to the general population. However, the exact risk varies depending on the study, and most aneurysms found are unruptured and asymptomatic.

What the research says

It is important to note that most of these aneurysms are unruptured and may not cause symptoms. The 2026 review found that aneurysm diagnosis occurred significantly later than pituitary adenoma diagnosis, suggesting that aneurysms may develop over time or be detected incidentally during imaging for the adenoma ³⁷. The 2019 study also found that most aneurysms were located in the internal carotid artery, which is near the pituitary gland, and that cavernous sinus invasion by the adenoma increased the risk ⁶. These findings suggest that the presence of a pituitary adenoma, especially a macroadenoma, may warrant screening for aneurysms, but more research is needed to establish clear guidelines.

What to ask your doctor

• Given my pituitary adenoma, what is my personal risk of having an intracranial aneurysm?
• Should I undergo any imaging, such as an MRI or CT angiogram, to screen for an aneurysm?
• Are there specific features of my adenoma, like size or invasion, that increase my risk?
• What symptoms of an aneurysm should I watch for, and when should I seek emergency care?
• How often should I be monitored for aneurysms if I have a pituitary adenoma?