Case of Desmoplastic Ameloblastoma Arising in the Anterior Maxilla

Desmoplastic ameloblastoma is a relatively rare subtype of ameloblastoma. Tumor resection with curettage is considered the most reliable treatment for desmoplasticameloblastoma because of its aggressive behavior with bone invasion. A 43-year-old Japanese man presented with a swelling on the left side of his anterior maxilla. A painless, bone-like hard swelling was observed in the anterior maxillary region. An orthopantomograph revealed a diffuse radiolucent area containing the root apices of the left maxillary lateral incisor and canine tooth. Computed tomography showed a well-marginated radiolucent area. Magnetic resonance imaging showed a well-circumscribed lesion with a signal intensity close to that of muscle tissue in the T1weighted image and slightly lower than that of adipose tissue in the T2-weighted image. Tumor resection with curettage was performed under general anesthesia. Histology of biopsy and resected samples showed scattered epithelial follicles resembling enamel organ and strands of epithelial cells in a coarse, collagen-rich fibrous stroma. Acanthomatous or microcystic changes were also observed in the parenchyma. These findings were consistent with those of desmoplastic ameloblastoma. No recurrence has been observed in the 3-year follow-up period. Curettage of the surrounding bone after tumor resection with sufficient margins prevents recurrence of desmoplastic ameloblastoma. DA is a subtype of ameloblastoma and grows with bone invasion. The risk of recurrence is high. However, early diagnosis and treatment of DA is possible because its preferred site is the anterior jaw.