Micro-invasive surgery combined with intraoperative radiotherapy for the treatment of spinal metastasis.

PURPOSE: This is a retrospective analysis of the strategy and clinical results of surgery combined with intraoperative radiotherapy (IORT) to treat spinal metastases.

METHODS: We delivered tumour-conformal IORT in 40 patients with 52 metastatic vertebrae based on our surgical classification system. The strategies were evaluated with respect to neurologic function and spinal stability. The EORTC QLQ-BM22, visual analogue scale (VAS) and the Frankel Scale were used to assess quality of life, pain and neurologic function. Local control was evaluated every 3 months using X-rays and MRI.

RESULTS: Micro-invasive IORT was performed in 42 vertebrae (80.8%), and open surgery with IORT was performed in 10 vertebrae (19.2%). Single-level, 2-level and 3-level IORT was performed in 30, 8 and 2 cases, respectively. The delivered dose was 9.2 ± 3.6 Gy (8-15 Gy) with a depth of 10.1 ± 2.1 mm. The actual IORT treatment time was 5 min and 16 s. The follow-up period was 6-23 months (mean: 12.5 months). The local control rate was 92.3%. The EORTC QLQ-BM22 scores showed that patients had significant improvements in pain location, degree and function after treatment (P < 0.01). Thirty-five patients (89.7%) achieved pain relief throughout the follow-up period. VAS scores were significantly reduced by 3.4 points 3 months after treatment. Neurological function was improved in 7 patients (87.5%). No radiation-related complications were observed.

CONCLUSIONS: Surgery combined with tumour-conformal IORT can effectively relieve pain, achieve good local control and improve QOL.