A 73-year-old female patient with a history of a metastasized nephrogenic carcinoma diagnosed in December 2005 was admitted to our University medical center for spondylodesis, decompression and tumor debulking of a large vertebral metastasis of L1 due to progressive pain in the dermatomal distribution of L1, L2 and the looming risk of acute compressive cord injury. Patient history included complete right- and partial left-sided nephrectomy as well as radio-chemotherapy of the abdomen and the spine for pulmonary, hepatic, pancreatic and osseous metastases. The most recent radiotherapy of L1 with up to 46.2 Gray had been documented three months prior to admittance and the current treatment palliative plan included receipt of combined immunotherapy medication (avelumab/axitinib) in addition to vitamin D, oral blood pressure medication (angiotensin-converting enzyme inhibitor, calcium channel blocker), and levothyroxine for previously diagnosed hypertension and hypothyroidism. Performance of the baseline neurologic exam of the patient upon admittance demonstrated an adequate mental status and unremarkable cranial nerve depiction. Testing of muscle strength against resistance as well as sensory perception of both arms and legs did not show any signs of motor or sensory deficit. However, the patient reported increasing pain of the right inguinal region with radiation to the right leg over the course of four weeks, restricting the previously unimpeded range of movement. Thoraco-abdominal computer tomography (CT) on the day of admittance showed progressive size of the L1-metastasis with infiltration of the paravertebral fat and protrusion into the spinal canal. Recommendation for pre-operative, endovascular embolization of the cord-compressing metastasis to reduce the risk of excessive intraoperative blood loss, was agreed upon in a multidisciplinary tumor board, to which the patient consented after being educated extensively on peri-interventional risks, especially the risk of an anterior spinal artery syndrome. The procedure was performed following an institutional standard operating procedure on a monoplane, ceiling-mounted angiographic system (Artis Q, Siemens Healthcare, Forchheim, Germany) under local anesthesia. The right femoral artery was accessed via a 5-French (F) vascular sheath (Avanti+, Cordis, Waterloo, Belgium), with insertion of an appropriate diagnostic catheter in the descending aorta. Acquisition of a C-arm computer tomography (CACT) was performed to gather precise anatomical information and enable further planning of the procedure. Catheterisation of the lumbar arteries demonstrated L1-L3 on the right and L1-L2 on the left to be involved in perfusing the vertebral metastasis L1. Arteriography of the lumbar artery L1 demonstrated additional contrast enhancements of the artery of Adamkiewicz, arising from the right intercostal artery T12. None of the other lumbar arteriographies showed involvement in spinal cord perfusion. Protective embolisations of non-tumor feeding branches of the lumbar arteries L2 (right) and L1 (left) via six different-sized coils was performed in preparation of the planned feeder artery embolization.
In immediate proximity to the planned surgical decompression and debulking procedure, a second angiography was conducted. A 4F-microsheath was inserted into the right femoral artery, proximally to the previous puncture site. Careful micro-catheterization (Merit Maestro with Tenor 0.014 guidewire, Merit Medical Systems, Utah, USA) and protective embolization of the proximal Adamkiewicz-artery was performed via coils of various forms and sizes. Additional protective coil-embolisation of muscle-perfusing arteries, arising from the right and left lumbar artery L1. Consecutive embolization of the tumor-feeding branches of the right- and left-sided T12, L1, and L2 via embospheres of 500–700 µm occurred, until achievement of stasis. Control angiography showed sufficient occlusion without residual flow of contrast. After removal of the catheter and sheath, an AngioSeal was placed at the puncture site due to plans of surgery performance in prone position. No inadvertent distal embolization occurred. Following decompression with laminectomy, nerve root decompression, wide tumor resection and debulking as well as pedicle screw instrumentation with minimal blood loss, the patient was discharged six days later with subjective well-being, especially no neurological deficits and is under active surveillance. Furthermore, the preoperative pain, which led to partial immobilization, completely resolved.