| Benign lesions | Malignant lesions |
| Congenital hypertrophy of the retinal pigmented epithelium (70–80%) | Thyroid cancer (2–3%) |
| Epidermoid cysts (50%) | Brain tumour (<1%) |
| Osteoma (50–90%) | Hepatoblastoma (∼1%) |
| Desmoid tumour (10–15%) | |
| Supernumerary teeth (11–27%) | |
| Adrenal gland adenomas (7–13%) |