Minimally invasive “separation surgery” plus adjuvant stereotactic radiotherapy in the management of spinal epidural metastases

AIM: This study aimed to describe the application of minimally invasive surgery (MIS) in separation surgery combined with postoperative stereotactic body radiation therapy (SBRT) in patients with symptomatic metastatic epidural spinal disease. METHODS: Three techniques are described: (1) MIS posterior separation surgery alone, (2) MIS posterolateral separation surgery with percutaneous pedicle screw placement, and (3) MIS lateral corpectomy with percutaneous pedicle screw placement. Seven representative cases are presented in which the above techniques were applied and after which postoperative SBRT was performed. RESULTS: The seven representative patients (3 male, 4 female) had a mean age of 54 years (range, 46–62 years). Two patients had a primary diagnosis of cholangiocarcinoma and in one patient each a diagnosis of breast, renal, lung adenocarcinoma, melanoma, and urothelial squamous cell carcinoma as their primary tumor. All patients had additional multiorgan disease apart from the metastatic spine involvement. Three patients underwent operations in the lumbar spine, two in the thoracic spine, and one in each of the thoraco-lumbar and lumbo-sacral spine. The average operating time was 149 ± 60.3 min (range, 90–240 min). The mean estimated blood loss was 188.8 cc. The mean length of stay in the hospital was 4 days (range, 3–7 days). There were no surgical complications. All patients received postoperative SBRT (typically 24 Gy in 3 fractions) at a mean of 43.2 days after surgery (range, 30–83). CONCLUSIONS: Early reports such as this suggest that MIS techniques can be successfully and safely applied in accomplishing “separation surgery” with adjuvant SBRT in the management of metastatic spinal disease. The potential advantages conferred by MIS techniques such as shortened hospital stay, decreased blood loss, reduced perioperative complications, and earlier initiation of adjuvant radiation are highly desirable in the treatment of this challenging patient population.