CT-guidance interstitial (125)Iodine seed brachytherapy as a salvage therapy for recurrent spinal primary tumors.

BACKGROUND

Management of spinal neoplasms has relied on open surgery and external beam radiotherapy (EBRT). Although primary spinal tumors are rare, their treatment remains a pervasive problem. This analysis sought to evaluate the safety and efficacy of CT-guided (125)I seed brachytherapy for recurrent paraspinous and vertebral primary tumors.

METHODS

From November 2002 to June 2014, 17 patients who met the inclusion criteria were retrospectively reviewed. 14 (82.4%) had previously undergone surgery, 15 (88.2%) had received conventional EBRT and 3 (17.6%) had chosen chemotherapy. The number of (125)I seeds implanted ranged from 7 to 122 (median 79) with specific activity of 0.5-0.8 mCi (median 0.7 mCi). The post-plan showed that the actuarial D90 of (125)I seeds were 90-183 Gy (median 137 Gy). The follow-up period ranged from 2 to 69 months (median 19 months). The local control rate was calculated by the Kaplan-Meier method.

RESULTS

For 5 Chondrosarcomas, the 1-, 2-, 3-year local control rates were 75%, 37.5%, and 37.5%, respectively, with a median of 34 months (range, 4-39 months). For 4 chordomas, the local control rate was 50% with a median follow-up of 13 months (range, 3-17 months). For 3 fibromatosis, all of them were survival without local recurrence at the end of follow-up. During the follow-up period, 35.3% (6/17) died from metastases, 17.6% (3/17) developed local recurrence by 8, 14 and 34 months while 64.7% (11/17) remained alive. 100% experienced pain relief and normal or improved ambulation, without more than Frankel grade 3 radiation myelopathy.

CONCLUSIONS

Percutaneous (125)I seed implantation can be an alternative or retreatment for recurrent spinal primary tumors.