Long‐term follow‐up results of spine tumor treatment using high‐dose radiotherapy after 3‐dimensional‐printed vertebral bodies implantation

OBJECTIVE: To investigate the long‐term safety and efficacy of high‐dose radiotherapy after 3D‐printed vertebral body implantation in the treatment of spinal tumors. METHODS: Thirty‐three participants were recruited between July 2017 and August 2019. 3D‐printed vertebral bodies were implanted in each participant, followed by postoperative robotic stereotactic radiosurgery at a dose of 35–40 Gy/5f. The tolerance of the 3D‐printed vertebral body and the participant to the high‐dose radiotherapy were evaluated. In addition, the local control of tumor and the local progression‐free survival of the study participants following 3D‐printed vertebral body implantation and high‐dose radiotherapy were measured as indexes of effectiveness. RESULTS: Of the 33 participants included in the study, 30, including three participants (10%) with esophagitis of grade 3 or above and two participants (6.7%) with advanced radiation nerve injury, successfully underwent postoperative high‐dose radiotherapy. The median follow‐up was 26.7 months, and IQR was 15.9 months. Most participants had primary bone tumors with 27 cases (81.8%), and the rest had bone metastases in six cases (18.2%). After high‐dose radiotherapy, the 3D‐printed vertebrae maintained good vertebral stability and exhibited histocompatibility, without implant fractures. The local control rates were 100%, 88%, and 85% 6 months, 1 year, and 2 years after high‐dose radiotherapy, respectively. Tumors recurred in four participants (12.1%) during the follow‐up period. The median local progression‐free survival after treatment was 25.7 months, with a range of 9.6–33.0 months. CONCLUSION: High‐dose radiotherapy for spinal tumors after 3D‐printed vertebral body implantation is feasible, elicits low toxicity, and yields satisfactory tumor control.