Cutaneous keratocysts of nevoid basal cell carcinoma syndrome.

Four cysts were removed from two unrelated patients with nevoid basal cell carcinoma syndrome. Multiple sections from each cyst were studied. Two cysts showed histologic features similar to keratocysts that occur in the jaws of patients with this syndrome. The cysts were lined by a festooned epithelium consisting of two to five layers of squamous cells that formed keratin without the presence of a granular cell layer. One cyst contained some lanugo hair and a small bud of follicular epithelium. This cyst was therefore similar to cutaneous steatocysts but did not have an identifiable sebaceous component. The second cyst was devoid of hair and adnexal structures and was indistinguishable from a jaw keratocyst. Two other cysts were typical epidermoid (infundibular) cysts. Although speculative, it is likely that some cutaneous cysts in patients with nevoid basal cell carcinoma syndrome are identical to jaw keratocysts and may be another cutaneous marker for this disease complex.