Benign cylindroma causing transcalvarial invasion in a patient with familial cylindromatosis

To describe a case of scalp cylindroma without features of malignancy invading through the skull and dura, and producing massive intracranial extension. Tumors of epidermis and epidermal appendages rarely show bony invasion, but invasive tendency in some tumor types has been associated with increased TP53 expression.

Patient with familial cyindromatosis (Brooke-Spiegler syndrome) who had undergone numerous previous surgical excisions over the past 30 years of his scalp cylindromas. Light microscopic and immunohistochemical characterization of resected tumor, with TP53 immunostaining in the invasive tumor was compared with that seen in five other cutaneous, non-invasive cylindromas.

Tumor showed no increase in mitotic rate or increased immunostaining for TP53.

Multiple previous surgeries down to pericranium may have contributed to local weakening of tissues and facilitated transcalvarial invasion. While an uncommon occurrence, both benign and malignant cylindromas have the capacity to invade bone, particularly in patients with the familial syndrome.