Clinical Application of Anterior Cervical Mini-Incision Vertebroplasty in the Treatment of Vertebral Metastases

Objective Through the retrospective study, the efficacy and safety of percutaneous vertebroplasty (PVP) in the treatment of cervical and upper thoracic metastases were evaluated. Through survival analysis, the accuracy of traditional spine metastases scoring system was evaluated, the prognostic factors affecting patients' survival outcomes were explored, and a new survival prediction model was established. Methods We retrospectively selected 85 patients with advanced cervical and upper thoracic metastases who were treated at Beijing Friendship Hospital from October 2012 to February 2018, including 65 patients with PVP surgery and 20 patients with internal medicine. All patients were in advanced stage of the tumor with severe neck and back pain, no spinal cord compression, and the estimated survival time was less than 6 months (Tokuhashi correction score ≤ 8 points or Tomita score ≥ 7 points). We collected basic patient information and survival time, as well as efficacy indicators before treatment and 3 days, 3 months, and 6 months after treatment, including VAS score, analgesic score, neck disability index (NDI), and daily life. State score (Karnofsky performance socre, KPS). Firstly, the differences in the efficacy index before and after PVP surgery, as well as the difference between the surgical and non-surgical treatment effects were compared. Secondly, the accuracy of Tokuhashi correction score, Tomita score and modified Bauer score was evaluated, and the difference in survival time of patients with different treatment methods was compared. Finally, the prognostic factors affecting the survival outcome were screened out and a new survival prediction model was constructed. Results All PVP surgery were successfully completed without serious complications. The cement leakage rates of the cervical and upper thoracic groups were 46.88% (15/32) and 33.87% (21/62), respectively. VAS score, analgesic score, NDI index and KPS score of PVP in cervical spine group were significantly improved compared with preoperative (P<0.05). VAS score, analgesic score, NDI score, and KPS score were also significantly improved in the upper thoracic group after PVP (P<0.001). There was no significant difference in the VAS score (P=0.341), analgesic score (P=0.444), and KPS score (P=0.587) between the cervical spine group and the upper thoracic spine group, but the NDI index of the cervical spine group improved better ( P < 0.001). Compared with the non-surgical group, the surgical group had better improvement in VAS score (P<0.001) and analgesic score (P=0.011), but there was no significant difference in KPS score (P=0.062). The area under the ROC curve for Tomita score was [0.679 (6 months), 0.793 ( 12 months), 0.756 (18 months)] and the predictive power of Tomita score was better than that of Tokuhashi correction score and modified Bauer score. The median survival time was 9 months in both surgical and non-surgical groups, with no significant difference (P=0.183). The median survival time of patients in the traditional medical treatment combined with target therapy group and the traditional medical treatment group were 16 months and 8 months, respectively, and the difference was significant (P<0.001). Tumor type, KPS score, targeted therapy, organ metastasis and bone metastasis were important prognostic factors affecting the survival outcome of patients with advanced cervical and upper thoracic metastases. Through these five factors, a new survival prediction model was established, the area under the ROC curve was [0.869 (6 months), 0.915 (12 months), 0.910 (18 months)], and the predictive ability was better than Tomita scoring system. Conclusion For patients with advanced cervical and upper thoracic metastases with short life expectancy, PVP could effectively relieve neck and back pain symptoms, improve quality of life. The analgesic effect of PVP surgery was better than that of conservative treatment, but there was no significant improvement in survival outcome. Targeted therapy was very important for the survival outcome of such patients.