Lesions, or tumors, of the skull are rare indeed, accounting for approximately 1% of bone tumors. As the name suggests, skull lesions are tumors that actually involve the skull. Some of these tumors are located on the base of the skull, where the brain sits. While treating skull lesions is basically straight-forward, obtaining an accurate diagnosis represents a significant clinical challenge.
There are several different types of non-cancerous skull lesions that are seen in children, and most of them are quite rare:
Fibrous dysplasia is a chronic disorder of the skeleton that causes expansion of one or more bones due to abnormal development of the fibrous, or connective, tissue within the bone. The abnormality will cause uneven growth, brittleness and deformity in affected bones.
- Dermoid/Epidermoid – This is a tumor-like mass that is benign (non-cancerous) and located on the skull. It is congenital and formed by skin cells that are deposited in the wrong place during the pregnancy.
- Eosinophilic granuloma – This occurs generally in children less than 12 years of age and is rare beyond the age of 20. It most commonly presents as a solitary, painful bone lesion on the skull. It is sometimes associated with Hand Schuller Christian disease, which occurs in children over 3 years of age.
- Fibrous dysplasia – Fibrous dysplasia is a chronic disorder of the skeleton that causes expansion of one or more bones due to abnormal development of the fibrous, or connective, tissue within the bone. Fibrous dysplasia can affect the skull through distal metastasis from such conditions as neuroblastoma. The fibrous dysplasia abnormality can cause uneven growth, brittleness and deformity in the skull.
- Nonossifying fibroma – This lesion is found mostly in children with 75% occurring in the teenaged years. The lesion is found in males more commonly that in females. In many instances, these lesions will resolve on their own.
- Xanthoma – This is a tough, painless, non-cancerous deposit of fat that develops beneath the skin on the skull.
- Lymphangiomas – This is a rare condition of the lymphatic system in which a mass grows near the skull. Lymphangiomas are non-cancerous, but surgical removal is complex because it involves the lymph nodes and occasionally the facial nerves.
Children’s Hospital of Orange County is a leader in diagnosing and treating skull lesions. The multidisciplinary team at The CHOC Neuroscience Institute are experts at diagnosing skull lesions and proving innovative treatment options.
Diagnosing Skull Lesions
The biggest challenge in treating skull lesions is diagnosing them – and differentiating them from other conditions. Each type of skull lesion mentioned above involves different areas of the skull, from the front of the skull to the mid-section to the back of the skull – to the skull base.
Physical findings may also vary according to the tumor type. The lesion may be tender or nontender to the touch, and soft or hard. Some tumors may cause nerve problems, resulting in hearing loss, vertigo and sensation loss.
Imaging tests are also crucial in helping diagnose skull lesions. These include skull X-ray images, computerized tomography (CT) head scans, magnetic resonance imaging (MRI), bone scans and arteriograms (if the lesion is vascular in origin).
A biopsy of the lesion is of key importance for establishing the diagnosis and considering treatment options. Many times, excisional biopsy is also curative.
Treating Skull Lesions
Many of these lesions can be completely removed for symptomatic relief, cosmetic relief, or to relieve cranial pressure. At The CHOC Neuroscience Institute, a multidisciplinary team of experts including pediatric neurosurgeons, neuro-oncologists and neuroradiologists together manage these skull lesions, providing individualized, tailored care to each patient.