[Recurrence and malignant transformation of intraosseous dentinogenic ghost cell tumor]

To describe the histologic and clinical findings of recurrent intraosseous dentinogenic ghost cell tumor (DGCT) and its malignant transformation.

The clinical features, treatment, pathology and prognosis of recurrent intraosseous DGCT patients from 53 cases of mixed odontogenic tumors with ghost cells and mesenchymal inductive components were retrospectively reviewed.

Ten recurrent cases from 14 DGCT were all male and the age at diagnosis ranged from 18 to 60 years with an average of 32.4 years. The main manifestation was progressive bone bulging. Radiographically the tumor was characterized by ill-defined radiolucency. Most recurrent tumors had entrenched the surrounding tissues. Seven cases occurred in the maxilla among which 2 cases were transformed into ghost cell odontogenic carcinoma and 2 showed features of increased cell proliferation. Three cases occurred in the mandible among which 1 case showed a high proliferative activity. The initial surgery of all recurrent cases was curettage.

The microscopic findings and prognosis suggested that intraosseous DGCT was locally aggressive. Multiple recurrences increased the risk of malignant transformation. Curettage alone might not be adequate for the management of DGCT. Maxillary cases with ill-defined borders, especially those showing an increased proliferative activity in biopsy or frozen section examination, should be treated more radically.