A Case of Metastatic Giant Cell Tumor of Soft Tissue of the Orbit Associated With PALB2 Variant

Giant cell tumor of soft tissue (GCT-ST) is a rare tumor described in the extremities or trunk, with rare cases reported in the ocular adnexa and orbit.¹ Although the tumors can be locally invasive, they are thought to have low malignant potential. In this report, we describe the case of a 34-year-old woman with GCT-ST arising in the orbit, who developed multiple recurrences with aggressive local invasion involving the skull base, and eventual pulmonary metastases. Next-generation sequencing revealed that the tumor was associated with a pathologic variant of PALB2.