A Rare CRTC1::NCOA2 Gene Fusion With a Novel NCOA2 Rearrangement in a Pediatric Patient With an Epithelioid Mesenchymal Neoplasm of the Spinal Cord

We present the case of a 12-year-old female who presented with progressive back pain and was found to have a localized mass in the lumbar spine. The resected tissue was characterized by epithelioid cells with a papillary appearance and high mitotic activity. Initial immunohistochemical analysis was consistent with a diagnosis of atypical meningioma. However, comprehensive molecular profiling detected a CRTC1::NCOA2 fusion with a novel NCOA2 gene rearrangement, leading to a revised descriptive diagnosis of epithelioid mesenchymal neoplasm with CRTC1::NCOA2 fusion. This specific fusion has only been reported in 2 other cases involving mesenchymal neoplasms of the palate and urinary bladder. While CRTC1 is frequently associated with MAML2 fusion in mucoepidermoid carcinomas, NCOA2 rearrangements occur in a variety of solid and hematologic malignancies. There is a paucity of information on the prognostic relevance of these fusion partners. This is the first reported case of a CRTC1::NCOA2 fusion in a pediatric patient with a spinal cord malignancy. The mechanistic significance and prognostic implications of this fusion will be discussed.