Abstract
Background: Osteoblastoma, a rare osteoblastic tumor, constitutes approximately 1% of all primary bone tu- mors. Aim: The purpose of this report is to present an osteoblastoma of the mandible, with particular emphasis on the differential diagnosis of this rare tu- mor. Methods-Results: the lesion showed osteoblast- like cells, stromal cells, osteoclast-like cells and inter- lacing trabeculae of osteoid. Because of the high cel- lularity of the tumor, immunohistochemical analysis was performed using the cell proliferation marker Ki-67, the p53 and the anti-apoptotic protein Bcl-2. The lesion demonstrated low to moderate prolifera- tive activity and no immunoreactivity was detected for p53. An interesting finding was the Bcl-2 expres- sion by the multinucleated osteoclast-like giant cells, in contrast to the lack of Bcl-2 expression from osteo- blast-like and stromal tumor cells. Conclusion: To our knowledge the Bcl-2 expression has not yet been in- vestigated in benign or malignant osteoblastic tumors. This finding may be related to the molecular mecha- nisms regulating the apoptosis of osteoclast-like tu- mor cells or their function.
Highlights
Osteoblastoma represents about 1% of all primary bone tumors
A weak expression for Ki-67 was detectable in the nuclei of osteoblast-like and stromal cells, in a percentage ranging from 10% to 25% of the tumor cells (Figure 2(d)), while no immunoreactivity was detected for p53
The differential diagnosis of osteoblastoma includes many jawbone lesions. This case was differentiated from osteoid osteoma due to the lack of the characteristic central bone nidus, which is a feature seen in osteoid osteoma [3,4,8]
Summary
Osteoblastoma represents about 1% of all primary bone tumors. Approximately 11% of the bone osteoblastomas are localized to the skull and nearly half of these cases involve the mandilble [1,2]. Osteoblastoma usually appears in the second decade of life as a painful expansion of the bone cortex with non specific radiographic appearance. It is characterized by osteoblastlike cells proliferation forming trabeculae of osteoid and immature bone in a highly vascularized stroma [2,3,4,5,6]. The purpose of this article is to present a case of osteoblastoma involving the anterior mandible with particular emphasis on the differential diagnosis and the immunohistochemical features of this rare tumor using the cell proliferation marker Ki67, the p53 and the antiapoptotic protein Bcl-2
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
