Special Poster Session 50th International Society for the Study of the Lumbar Spine Annual Meeting 2024

TOTAL EN BLOC SPONDYLECTOMY FOR PRIMAY MALIGNANT AND LOCALLY AGGRESSIVE INTERMEDIATE BONE TUMORS ARISING IN THE LOWER LUMBAR SPINE (#SP-10f)

Yoshihiro Matsumoto 1 , Keiichiro Iida 2 , Yoshihiro Kobayashi 1 , Hiroshi Kobayashi 1 , Kinshi Kato 1 , Kazuyuki Watanabe 1 , Takuya Nikaido 1
  1. Fukushima Medical University, Fukushima, FUKUSHIMA, Japan
  2. Shimonoseki city hospital, Shimonoseki

Introduction: Total en bloc spondylectomy (TES) is a complex surgical procedure used in the treatment of primary malignant and locally aggressive intermediate tumors in the spine. This procedure involves the complete removal of an entire vertebral body and its posterior elements in an attempt to achieve tumor removal with clear margins. Performing TES in the lower lumbar spine (L3, L4, and L5) presents unique challenges due to the proximity of important structures such as the lumbar plexus, major blood vessels, and the bowel. However, there is a limited amount of clinical information available regarding TES in the lower lumbar spine.

Methods: This study included seven patients who underwent TES for primary bone tumors in the lumbar spine. The patients had an average age of 48 years (ranging from 28 to 66), with one male and six females. The average follow-up period was 81 months (ranging from 17 to 144 months). We collected information from their medical charts.

Results: All surgeries were performed using a posterior-anterior approach. In the posterior approach, the posterior part of the spine was resected, and the lumbar nerve roots were dissected laterally. This was followed by posterior fixation using instrumentation and a substantial bone graft. Subsequently, via a transperitoneal approach in collaboration with a vascular surgeon, the affected vertebra was removed, and an artificial vertebra was placed. The tumors' sites of origin were as follows: L3 in three cases, L4 in one case, and L5 in three cases. According to the Tomita classification, the extension of the tumors was assessed as Type 1 in one case, Type 4 in five cases, and one case was not classified due to previous surgery. The histological diagnosis of the tumors was as follows: giant cell tumor of bone (GCTB) in four cases, chondrosarcoma in one case, histiocytosarcoma in one case, and undifferentiated pleomorphic sarcoma in one case.

The average blood loss was 3,570 mL (ranging from 941 to 6,413 mL), and the average operative time was 991 minutes (ranging from 754 to 1,413 minutes). Five patients remained disease-free, and one patient with GCTB showed no evidence of disease after receiving radiotherapy for recurrent tumors. Unfortunately, one patient died of disease due to multiple metastases. In one case, postoperative leg pain worsened but improved during the final follow-up. Additionally, two cases showed implant loosening at the upper instrumented vertebra; however, revision surgery was not performed due to the absence of symptoms.

Discussion: While favorable oncological outcomes related to local control and survival can be achieved with TES for primary malignant and intermediate bone tumors in the lower lumbar spine, it is important to acknowledge that this procedure is one of the most challenging operation in the field of spine surgery. Furthermore, the risks associated with perioperative complications and late instrumentation failure should be taken into account. Therefore, future research into strategies for avoiding complications and improving reconstruction techniques is encouraged.