Pilosebaceous Malignant Transformation of Dermoid Cyst in the Orbit

Dermoid cysts may occur in the orbit, most commonly in the superolateral area. Malignant transformation of such lesions has been previously reported; however, most turn out to be squamous cell carcinoma. The authors’ patient initially presented with mild proptosis and limitation in extraocular movements. Preliminary biopsy showed whitish amorphous material and abundant hairs filling the thin-walled cyst, consistent with dermoid cyst. The patient...