Subretinal Bone Formation in a Patient with Giant Cell Tumor of the Sphenoid.

BACKGROUND/AIMS To report a case of subretinal bone formation after the treatment with denosumab for a giant cell tumor of the sphenoid, which had recurred after surgical resection. METHODS The clinical history and fundus findings including imaging, histologic and immunohistochemical features of the primary tumor and subretinal lesion were reviewed. RESULTS A 14-year-old boy was evaluated for a suprasellar mass. Resection of the lesion showed giant cell tumor of bone (GCT). An MRI study at the 1-month follow-up appointment showed tumor progression, and denosumab was initiated. Two months after the initial presentation, the patient developed a worsening scotoma of the right eye. Dilated fundus examination showed a yellow-tan-colored subretinal mass temporal to the fovea. The subretinal lesion was removed and showed lamellar bone with associated fibrocellular tissue. CONCLUSION Denosumab therapy for GCT of the sphenoid may be associated with subretinal bone formation.