Open microwave ablation combined with decompression and internal fixation for vertebral metastases：a followup report

CHEN Bing-yao; WEI Xing; SHI Ya-min; LI Nan; MA Yun-qing; SONG Guang-ze; ZHANG Zeng-liang; WANG Shuo; HOU Shu-xun

doi:10.3969/j.issn.2095-252X.2014.05.006

Abstract：Objective To evaluate the clinical outcomes of open microwave ablation combined with decompression and internal ifxation in the treatment of vertebral metastases. Methods From March 2006 to December 2010, a total of 76 patients with vertebral metastases were adopted, including 48 males and 28 females. Their average age was 57.4 years old ( range;34-80 years ). One single vertebral body was involved in 51 cases, 2 vertebral bodies in 22 cases and 3 vertebral bodies in 3 cases. Lesions were found in the thoracic vertebra ( n=44 ), the lumbar vertebra ( n=16 ), the cervical vertebra ( n=6 ), the sacral vertebra ( n=2 ), the cervicothoracic segment ( n=4 ) and the thoracolumbar segment ( n=4 ). Among the 55 patients with neurological deficits, 6 patients had complete spinal cord injuries ( SCI ). According to the Tomita classiifcation system, 88.2%of the patients belonged to type IV-VI. The Tomita prognostic scores were 3-6 points in most patients. Patients underwent the treatment of open microwave ablation combined with decompression and internal fixation. Following laminectomy, microwave antennas were inserted into the vertebra via the pedicles to induce ablation. During this process, the spinal canal was cooled with saline to protect the spinal cord. Short-segment pedicle ifxation was used as an assistance. Results All the patients were followed up for 2-57 months, and the median follow-up time was 24 months. The mean operation duration was 120 min, and the intraoperative blood loss was 457 ml on average. Pain was obviously relieved after the operation. The mean Visual Analogue Score ( VAS ) was 6.4 points before the operation, which was decreased to 2.2 points at 1 month after the operation. There were statistically signiifcant differences between them ( P<0.05 ). The total survival rate was 71%, with 54 patients alive and 22 patients dead at 9.9 month after the operation on average ( range;2-33 months ). Among the 55 patients with neurological deifcits before the operation, 49 patients gained walking ability and the 6 patients with complete SCI did not. Recurrence occurred to 9 cases, with 6 cases in the thoracic vertebra, 2 cases in the lumbar vertebra, 1 case in the cervical vertebra and 1 case in the sacral vertebra. The recurrence rate was 12%, and the mean recurrence time was 9.1 months ( range;2-18 months ). Neurological complications were found in 3 cases, and delayed healing of wounds in 6 cases. One patient with secondary infection recovered after debridement. Conservative treatment was performed on 9 patients with cerebrospinal lfuid leakage, 3 patients with lower limb deep venous thrombosis and 3 patients with pulmonary infection, who all recovered. Conclusions Open microwave ablation combined with decompression and internal ifxation is a potentially promising technique in the treatment of vertebral metastases, with the advantages of minimal trauma, well relieved pain, good postoperative functional recovery and higher local control rate.