Surgery and permanent 125I seed paraspinal brachytherapy for malignant tumors with spinal cord compression

To evaluate the functional outcome, predictors of response, and toxicity from spinal surgery and 125I brachytherapy in patients with malignant tumors resulting in spinal cord compression.

Between July 1985 and September 2001, after surgical resection, 30 patients underwent 31 intraoperative paraspinal brachytherapy procedures at Barrow Neurological Institute. Twenty-four (with 25 procedures) had follow-up at our clinic and form the basis for this report. Surgical procedures were based on the location of the impinging lesion: corpectomy or spondylectomy in 13 cases and laminectomy in 12. Permanent 125I seeds in absorbable suture were placed with open exposure after resection.

Spinal cord compression was cervical in 4 (16%), thoracic in 14 (56%), and lumbar in 7 (28%) of the 25 cases. One patient underwent two separate procedures at different spinal sites. Of the 25 brachytherapy sites, 22 also received external beam radiotherapy (EBRT): 5, EBRT with a planned brachytherapy boost; 4, brachytherapy and prompt EBRT after recovery; and 13, brachytherapy as salvage for local failure after prior EBRT. Three had no EBRT: 1 had lymphoma treated with chemotherapy, 1 had remote previous EBRT for a childhood tumor, and 1 refused EBRT. The mean follow-up was 19.8 months. The 2- and 3-year actuarial local control rate was 87.4% and 72.9%, respectively. Four sites (16.0%) experienced local failure. The mean time to recurrence for these 4 patients was 20.3 months. Three of the four had failed prior EBRT, with surgery and brachytherapy used for salvage. The 2- and 3-year actuarial overall survival rates were 24.0% and 16.0%, mean 19.2 months. An ambulatory function score was assigned pre- and postoperatively: I, normal ambulation; II, abnormal not requiring assistance; III, abnormal requiring assistance; and IV, unable to ambulate. All patients with score I, 91% of those with score II, 67% of those with score III, and 67% of those with score IV were ambulatory after the procedure; 84% had either normal or improved ambulation postoperatively. Morbidity was restricted to four postoperative events: one cerebrospinal fluid leak, two wound infections treated in situ without removal of seeds or instrumentation, and one pulmonary embolus. No myelopathies or other neurologic sequelae were encountered.

This is the largest series in the literature exploring surgery and 125I brachytherapy in the treatment of malignant spinal cord compression. We found this to be well tolerated and to result in durable local control and ambulatory function. Our results suggest a benefit to aggressive local therapy in selected patients with spinal cord compression.