Understanding PHACE Syndrome

PHACE syndrome is a rare condition where a large, visible birthmark on a child’s skin—specifically an infantile hemangioma—serves as a “clue” to other health issues that might be happening inside the body ^[1][2].

It is known as a neurocutaneous (nerve and skin) or developmental association of uncertain cause ^[1]. This means that when the baby was developing in the womb, the skin, brain, heart, and eyes were all affected at the same time. It is not a cancer, and the skin mark is not “spreading” to the organs; rather, the skin mark and the internal differences simply developed together. A hemangioma may be present at birth or appear soon afterward ^[2].

Breaking Down the Name

The name PHACE is an acronym, where each letter stands for a part of the body that doctors check for potential differences:

• P (Posterior fossa): The back part of the brain. Doctors look for structural differences in the cerebellum, which is the part of the brain that controls balance and coordination ^[3][4].
• H (Hemangioma): A bright red, raised birthmark made of extra blood vessels. In PHACE, these are usually segmental, meaning they cover a “patch” or territory of the face, neck, or scalp ^[5][6].
• A (Arterial): The blood vessels that carry oxygen to the brain and heart. These may be narrow, twisted, or follow an unusual path ^[7][8].
• C (Cardiac): The heart. The most common finding is coarctation of the aorta, where the main artery leaving the heart is narrower than it should be ^[7][9].
• E (Eye): Differences in how the eyes or optic nerves (the nerves that carry signals to the brain) are formed ^[10][11].
• S (Sternal): Occasionally, a small “notch” in the breastbone (sternum) or a thin line on the skin of the upper abdomen called a supraumbilical raphe is present ^[12].

Who Does It Affect?

PHACE syndrome is rare. While we don’t have a perfect count for the whole world, some population-based studies in Europe suggest it may occur in about 0.59 to 6.5 per million children, though estimates vary based on the study ^[13].

One of the most consistent findings is that it affects girls much more often than boys. In several large medical studies, roughly 77% to 90% of children diagnosed with PHACE were female ^[14][15]. The reason for this strong female predominance is still being researched ^[1].

Misunderstandings About the Hemangioma

Because PHACE was first described in children with very large, obvious red birthmarks, there are several common misunderstandings about what the “H” in PHACE must look like:

• Size isn’t the only factor: While many children with PHACE have a hemangioma larger than 5 centimeters (about 2 inches), smaller marks can also be associated with the syndrome ^[16][6].
• Deep hemangiomas count: Some hemangiomas are “deep,” meaning they look like a bluish swelling under the skin rather than a bright red “strawberry” mark. These can still be a sign of PHACE if they are in a segmental pattern on the face or neck ^[6][16].
• Minimal growth: Some children have “minimal growth” hemangiomas that stay flat and look like a faint stain or a bruise that doesn’t fade. These “arrested growth” marks can still be associated with internal PHACE features ^[6].
• Not all features are required: Most children with PHACE do not have every single feature in the acronym. Diagnosis is based on having the right kind of hemangioma plus at least one “major” or two “minor” internal findings ^[5][17].

Building a Care Team

Because PHACE can involve many parts of the body, your child will likely need a multidisciplinary team—a group of specialists working together. This team often includes a pediatric dermatologist (skin), a pediatric cardiologist (heart), a pediatric neurologist (brain), and a pediatric ophthalmologist (eyes) ^[5][18].

The first step usually involves imaging, such as an MRI (Magnetic Resonance Imaging) of the brain and an MRA (Magnetic Resonance Angiogram) to look at the blood vessels, to ensure everything is functioning safely ^[18][16]. While this can feel overwhelming, these tests help your child’s doctors create a proactive plan for their health ^[5].