Abstract
Carcinoma cuniculatum （CC） is a subtype of squamous cell carcinoma. Characteristic histological findings include proliferation of stratified squamous epithelium and infiltration of underlying stroma exhibiting a cuniculatum （i.e., rabbit burrow） structure. Although of low malignancy, CC often progresses locally and destroys bone. About 50 cases of CC in the maxilla and oral cavity have been reported worldwide. We describe a case of CC in a 63-year-old woman who previously received a diagnosis of, and underwent surgery for, odontogenic keratocyst （OKC） at another hospital. After surgery, she developed widespread relapse, including intraorbital and nasal bone invasion, for which she sought treatment at our hospital. She underwent extended total maxillectomy, and the final diagnosis was maxillary CC with OKC components.
