Osteoblastoma is a benign neoplasm which commonly occurs in the vertebral column and long bones. The tumour grows slowly and rarely recurs after surgery. This report presents the clinicopathological and radiological findings of a case of recurrent osteoblastoma in the maxilla. A 7-year-old male patient visited our department with chief complaints of left facial swelling and pain. A panoramic radiograph showed a homogeneous radio-opaque expansile lesion in the left maxilla. The lesion was thought to be fibrous dysplasia and the patient underwent a surgical excision using the Caldwell-Luc procedure. Histopathological examination of the lesion confirmed it as benign osteoblastoma. The lesion recurred 6 months after the initial surgery. CT images revealed a large mass with multiple internal calcifications. Subsequently, the patient underwent mass excision with subtotal left maxillectomy. Follow-up CT scans at 1 year intervals showed no recurrence for 5 years. Dentomaxillofacial Radiology ( Keywords: osteoblastoma; recurrence; X-ray computed tomography
Case reportA 7-year-old male patient visited our department with the chief complaints of left facial swelling and pain. His medical history was unremarkable. Clinical and radiographic examinations were performed. Intraoral examination revealed a firm gingivobuccal swelling extending from the left maxillary deciduous lateral incisor to the left maxillary permanent first molar. Panoramic radiographs showed a homogeneous radio-opaque expansile lesion in the left maxilla and the lesion involved the whole maxilla. The adjacent tooth germs were displaced and the innominate line in the left maxillary sinus was not detected (Figure 1). The lesion was thought to be fibrous dysplasia from the initial clinical and panoramic radiographic findings; therefore, mass excision using the Caldwell-Luc operation was performed. The surgical specimen was 3.5 cm in diameter and it was spherical, encapsulated and firm tissue. On histopathological examination, bony trabeculae surrounded by a single layer of plump osteoblasts of high cellularity were observed in the stroma. There was no atypia or mitotic activity in the osteoblasts or in the mesenchymal cells of the stroma. Most of the calcifications consisted of woven bone without obvious lamellation. Multinuclear giant cells were often identified around the osteoid. As the trabeculation progressed, the stroma changed into loose fibrovascular tissue. The lesion was finally diagnosed as benign osteoblastoma (Figure 2).The patient revisited our department with an enlarged swelling in the same region 6 months after the operation. CT images revealed a large well-defined mass composed of two locules with multiple internal calcifications. Owing to the expansive nature of the lesion, the left orbital floor was elevated and the lateral wall of the left nasal cavity was pushed towards the medial side (Figure 3). The patient had undergone mass excision with subtotal left maxillectomy. The surgical specimens were composed of two, solid, firm soft-tissue ...