A triton tumor is a malignant peripheral nerve sheath tumor (MPNST) with rhabdomyomatous differentiation These tumors account for 5% of MPNSTs and have an extremely poor prognosis. We describe the case of a 14-year-old girl who presented with a history of painful, progressive protrusion of her right eye with a diminution of vision for the past five years. She had been diagnosed as having an embryonal rhabdomyosarcoma of the right orbit, and she had undergone surgical debulking followed by chemotherapy and radiotherapy. Despite undergoing multiple modalities of treatment, she had several recurrences prior to this consultation. We reviewed her histology slides. HPE features were consistent with a malignant triton tumor with cartilage and osseous differentiation. Immunohistochemistry was done to confirm the diagnosis. In view of the aggressive nature of the tumor with multiple recurrences; she was advised palliative radical excision to reduce the tumor burden.

https://www.tandfonline.com/doi/full/10.1080/01676830.2019.1692873