A Case of Radiation-Induced Osteosarcoma with RB1 Gene Alteration Treated by Skull Base Surgery and Craniofacial Reconstruction

A 35-year-old female presented with headache, photophobia and developed sudden loss of vision after having undergone right-side ophthalmectomy and radiochemotherapy for retinoblastoma in infancy. A neoplastic lesion was found in the left middle cranial fossa and was surgically removed. The diagnosis was radiation-induced osteosarcoma with RB1 gene alteration. Although she received chemotherapy for the residual tumor, it progressed 17 months later. Maximal surgical resection with craniofacial reconstruction was required. We utilized two three-dimensional models for surgical planning. She was discharged without neurological deficits other than loss of light perception subsequent to left ophthalmectomy. In cases where retinoblastoma is treated with radiotherapy, long-term follow-up is necessary to monitor for radiation-induced tumor development.