The Role of Minimal Access Surgery in the Treatment of Spinal Metastatic Tumors

Abstract

Study design: Literature review.

Objective: To provide an overview of the recent advances in minimal access surgery (MAS) for spinal metastases.

Methods: Literature review.

Results: Experience gained from MAS in the trauma, degenerative and deformity settings has paved the road for MAS techniques for spinal cancer. Current MAS techniques for the treatment of spinal metastases include percutaneous instrumentation, mini-open approaches for decompression and tumor resection with or without tubular/expandable retractors and thoracoscopy/endoscopy. Cancer care requires a multidisciplinary effort and adherence to treatment algorithms facilitates decision making, ultimately improving patient outcomes. Specific algorithms exist to help guide decisions for MAS for extradural spinal metastases. One major paradigm shift has been the implementation of percutaneous stabilization for treatment of neoplastic spinal instability. Percutaneous stabilization can be enhanced with cement augmentation for increased durability and pain palliation. Unlike osteoporotic fractures, kyphoplasty and vertebroplasty are known to be effective therapies for symptomatic pathologic compression fractures as supported by high level evidence. The integration of systemic body radiation therapy for spinal metastases has eliminated the need for aggressive tumor resection allowing implementation of MAS epidural tumor decompression via tubular or expandable retractors and preliminary data exist regarding laser interstitial thermal therapy and radiofrequency ablation for tumor control. Neuronavigation and robotic systems offer increased precision, facilitating the role of MAS for spinal metastases.

Conclusions: MAS has a significant role in the treatment of spinal metastases. This review highlights the current utilization of minimally invasive surgical strategies for treatment of spinal metastases.

Keywords: minimal access surgery; minimally invasive surgery; spine; surgery; tumor.

Figure 1.

Minimal access treatment algorithm for metastatic thoracolumbar compression fractures. Adapted from Barzilai et al.

Figure 2.

A 43-year-old woman who presented with newly diagnosed squamous cell carcinoma of thymic origin. Evaluated for severe biologic pain, no evidence of mechanical instability and with high-grade spinal cord compression at T2. She underwent a minimally invasive tubular decompression with percutaneous stabilization followed by stereotactic body radiation therapy (SBRT). At 3 months postoperatively, the patient was neurologically intact, pain free, no evidence of viable tumor on magnetic resonance imaging. (Left) Preoperative axial T2 demonstrating high-grade epidural spinal cord compression. (Right) Three-month follow-up, postoperative changes demonstrated with no residual cord compression.

Figure 3.

A 58-year-old woman with widely metastatic breast cancer to the lymph nodes, bone, liver, and pleura presented with progressive lower back pain secondary to a previously irradiated L5 metastatic lesion. She developed significant mechanical radiculopathy in the left L5 distribution and magnetic resonance imaging (MRI) demonstrated progression of a compression fracture with severe foraminal stenosis. She underwent a minimally invasive left L5-S1 left hemifacetectomy along with L4-S1 instrumented stabilization with cement augmentation. At 3-month follow-up, her preoperative pain has significantly decreased and patient regained full ambulation. (Left) Preoperative MRI; (top) axial T1 with contrast demonstrating the foraminal disease and (bottom) T1 without contrast demonstrating the fracture compressing the exiting nerve root. (Right) (top) postoperative computed tomography demonstrating the left sided hemifacetectomy and (bottom) postoperative x-ray showing the stabilizing construct with cement augmentation.

Figure 4.

A 43-year-old man with newly diagnosed IgG-lambda multiple myeloma with anemia, hypercalcemia, acute renal failure (ARF), and bone lesions at initial presentation. He presented with severe, progressive, and debilitating movement-related back pain localized in his mid to lower thoracic region. His magnetic resonance imaging (MRI) demonstrated multilevel compression fractures most notably a T8 planum burst fracture with a mild kyphotic deformity but without significant spinal cord compression. He was not able to tolerate transport into the hospital for oncologic therapy and hence pain palliation was necessary. He underwent T7-T9 percutaneous instrumentation with cement-augmented screws, and kyphoplasty at T10, T11, T12, and L1. He went on to chemotherapy and bone marrow transplantation and at 6-month follow up reported minimal (1/10) back discomfort. (Left) Preoperative sagittal MRI STIR (short tau inversion recovery) demonstrating the multilevel compression fractures. (Center) Sagittal standing postoperative x-ray. (Right) Anterior-posterior standing postoperative x-ray.