[Relief effect of CT-guided (125)I seed implantation on patients with spinal and paraspinal osteolytic metastatic tumors].

Objective: To evaluate the clinical value of computed tomography (CT)-guided (125)I seed implantation in the treatment of patients with spinal and/or paraspinal osteolytic metastatic tumors. Methods: The radiation dose distribution was planned for 27 patients with 35 spinal and paraspinal osteolytic metastatic tumors by a treatment planning system (TPS). CT-guided (125)I seed implantation was carried out in the patients, and the quality of treatment was evaluated based on CT-imaging follow-up. Results: All the 27 patients underwent CT-guided (125)I seed implantation successfully. 12 to 50 (125)I seeds were injected into each spinal or paraspinal metastatic tumor, 39.15 on average, and the specific radioactive activity of the particles ranged from 0.60 to 0.80 mCi, 0.73 mCi on average. The minimal percentage of the dose received by 90% of the target volume (D(90)) of the spinal and paraspinal metastatic tumors ranged from 90 to 165 Gy, 115.03 Gy on average. Among the 27 patients, 21 (77.8%) had partial remission (PR) and 6(22.2%)had stable disease (SD). The Numerical Rating Scale (NRS) scores before implantation and at postoperative 3 and 6 months were 7.81±0.74, 2.04±1.10 and 1.81±0.79, respectively, (P<0.05). The assessment of pain intensity before (125)I seed implantation and at 3 postoperative months showed obvious improvements in the patients evaluated according to the American Spinal Injury Association (ASIA) impairment scale: 12 (44.4%) patients with ASIA grade C were changed to grade D, 3 (11.1%) from grade C to grade E, 8 (29.6%) from grade D to grade E, 3 (11.1%) with a stable grade D, and 1 (3.7%)with a stablegrade C. The Karnovsky performance scale (KPS) scores before treatment and at 3 months and 6 months postoperatively were 66.30±6.88, 85.93±9.31 and 87.91±8.56, respectively (P<0.05). Their local control rate (LCR) at 3 months, 6 months and 1 year postoperatively were 100%, 92.6% and 51.9%, respectively, and the overall survival rates(OSR) were 100%, 92.6% and 55.6%, respectively. Conclusions: CT-guided (125)I seed implantation can significantly relieve local pain, has advantages of less complications and higher local control rate. Therefore, it is a safe, effective and feasible treatment option for patients with spinal and paraspinal osteolytic metastatic tumors.