Background: GIANT CELL TUMOR is a benign but locally aggressive bone neoplasm, which uncommonly involves the skull. GIANT CELL TUMOR (GCT) of the sphenoid bone is relatively rare. In this report, we describe a TUMOR of the greater wing of left sphenoid bone.Case presentation: A 31-year-old female was presented with headache, proptosis and diplopia of her left eye. Cranial magnetic resonance imaging and CT scan showed an enhancing TUMOR at the junction of the orbital apex, ethmoidal and sphenoid sinuses. The TUMOR was removed and pathological examination confirmed a GIANT CELL TUMOR. Conclusion: This is the second report to describe the appearance of a GCT of the part of sphenoid bone which caused proptosis of the unilateral orbit. Radical excision of TUMOR was achieved which may be curative.

TUMORs originated from nose and paranasal sinuses consist 0.2%-0.8% of total malignancies of the body. This case report introduces a l4-year-old female who during examining for evaluation of epitasis following trauma, was found to have extensive abnormalities in the sinuses and a space occupying mass in the left maxillary and ethmoidal sinuses. GIANT CELL reparative granuloma is classified as a benign TUMOR, and is usually found in young patients and is usually associated with trauma. This lesion is an uncontrollable osteogeneticreaction.Treatment of this disease consists of preseruative surgicalr esoction of the TUMOR without unnecessary procedures.

Background and Objectives: Peripheral and central GIANT-CELL granulomas (PGCGs and CGCGs) and GIANT-CELL TUMOR (GCT) of bone have similar histopathological features with different biological behavior. The aim of this study was to evaluate the expression of transforming growth factor beta (TGF-β ) in these lesions by the help of immunohistochemistry. Materials and Methods: In this study, 15 PGCGs, 15 CGCGs, and 10 GCTs were evaluated. The TGF-β immunoreactivity was assessed in mononuclear CELLs (MC) and multinucleated GIANT CELLs (MGC) of the studied groups. Data analysis was performed using Kruskal-Wallis and Dunn’ s tests. Results: There was a significant difference between three studied groups regarding both MCs and MGCs. The highest mean of TGF-β immunostaining was observed in GCTs and the lowest in PGCGs. In pairwise comparison of the studied groups, a significant difference was observed between PGCGs and GCTs considering both MCs and MGCs. Additionally, a significant deference was reported only in MCs between CGCGs and GCTs. Conclusion: The results may explain the different biological behavior and pathogenesis of these lesions despite the similarity of histopathologic features.