C0449 - CERVICAL C1-C2 METASTASIS FROM A DUODENAL GIST COMPROMISING THE RIGHT VERTEBRAL ARTERY
Hospital General Universitario Gregorio Marañón, Madrid, Spain.
Objectives: The aim of this work is to present a case report from a patient diagnosed with a gastrointestinal stromal tumour (GIST), who developed cervical metastasis at C1-C2 level, compromising the right vertebral artery.
Methods: We present a patient with a cervical metastasis from a duodenal GIST. To prevent ischemic complications, the right vertebral artery was occluded prior to the surgery. A review of the relevant literature was performed.
Results: A 69-year-old male, diagnosed in 2014 with a duodenal GIST, peritoneal implants and vertebral metastases was successfully treated with surgery and Imatinib. Two years later, he complained of right-sided neck pain, and presented a stiff and painful retromastoid mass. PET-CT showed a right laterocervical mass at C1-C2 level, located in the paravertebral musculature and infiltrating the C1 transverse foramen and the C1-C2 neural foramen. A core needle biopsy obtained the diagnostic of a GIST metastasis, infiltrating striatal muscle. An MRI showed a mass in the right great oblique muscle of the head, engulfing the V3 segment of the right vertebral artery, affecting the spinal canal through the right C1-C2 foramen. To ease the surgery the distal V2 segment of the right vertebral artery was occluded with coils, and a week later, the tumour was surgically removed using a laterocervical approach and a milling of the C1 transverse process. Anatomical pathology showed fusocelular cells with eosinophil cytoplasm and dense chromatin in a collagenous stroma, infiltrating the striatal muscle. They were immunoreactive for CD117 antigen (C-Kit), CD34 and DOG-1. Ki67 reached 40%. The literature in English was reviewed rendering 7 cases of skeletal muscle metastasis from a GIST, and just in 1 case this was seen in the cranio-vertebral junction.
Conclusions: A case report from a cervical GIST metastasis is presented, being the second case published. If feasible, striatal muscle metastasis should be completely surgically excised.