Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms arising from the gastrointestinal tract. The authors present a case of the successful removal of a metastatic GIST in the craniovertebral junction, using an occipital artery to posterior inferior cerebellar artery (OA-PICA) bypass. The patient is a 54-year-old male who underwent his first surgery for a small-bowel tumor at the age of 45 and was diagnosed with GIST. Nine years after his primary diagnosis, the patient suffered from severe neck pain. MRI demonstrated a large demarcated mass adjacent to the right atlas. The right vertebral artery (VA), completely engulfed by the tumor, showed a narrowing and ended in the PICA. Poor collateral blood supply in the right PICA territory was presumed. To prevent ischemic complications, an OA-PICA bypass was performed prior to the tumor resection. After the OA-PICA bypass, the tumor associated with the right VA was successfully removed, and the patient was discharged without any neurological deficits.
Keywords: Craniovertebral junction; Gastrointestinal stromal tumor; Metastasis; Occipital artery to posterior inferior cerebellar artery bypass; Prophylactic vascular reconstruction; Tumor resection.