External beam radiotherapy for primary spinal cord tumors

Abstract

Of 34 evaluated patients with primary spinal cord tumors, 32 were irradiated at our institutions between 1969 and 1983. The results are reported of 32 patients, 16 with ependymoma and 16 with astrocytoma, who were treated with postoperative external beam radiotherapy following biopsy or subtotal resection. Twenty-nine patients received 45-55 Gy megavoltage beam irradiation in five to six weeks, and the remaining three patients received less than 40 Gy. The minimum follow-up was five years. Five- and ten-year actuarial survival rates for the entire group of patients were 73% (22/30) and 50% (8/16), respectively, including three patients who were salvaged by surgery after radiotherapy failures. Corresponding five- and ten-year relapse-free survival rates were 60% (18/30) and 32% (6/19), respectively. Of the 29 patients who received more than 45 Gy, relapse-free survival at five years was 63% (17/27). Treatment failed in 13 patients, and all of those failures were within the irradiated portals. Patients with ependymomas have significantly better relapse free survival than those with astrocytomas, 80% vs. 40% (p less than 0.05). There was a significant difference in survival between patients with tumors involving the cervical spine and those with tumors in the other locations, 45% vs. 89% (p less than 0.05). There was no significant difference in survival between patients with cauda equina tumors and those with tumors of the spinal cord, 100% vs. 68% (p less than 0.05). No radiotherapy-related neurological deficit was noted with a maximum 20 year follow-up. This study confirms that external beam radiotherapy is a safe and effective treatment modality for primary spinal cord tumors.

Chemotherapy for spinal cord astrocytoma

“…There is no convincing evidence that low grade astrocytomas are sensitive to radiotherapy. Although there may be series in which an apparently favorable long-term response to radiotherapy is recorded [7][8][9][10][11], this could be related to the indolent biology of the tumor rather than to the response to radiotherapy. Moreover the optimal dosage of radiotherapy remains unknown.…”

“…For some authors, additional radiotherapy is thought more likely to give the best chance of long-term survival [7][8][9][10][11].…”

Carboplatin chemotherapy for progressive intramedullary spinal cord low-grade gliomas in children: Three case studies and a review of the literature

“…For many years, the use of radiotherapy as an adjuvant treatment has been accepted practice after either diagnostic biopsy or attempted resection in both pediatric and adult patients with intramedullary spinal cord low-grade gliomas (Chun et al, 1990;Constantini et al, 1996;Doireau et al, 1999;Epstein et al, 1992;Linstadt et al, 1989;Lowis et al, 1998;O'Sullivan et al, 1994;Rossitch et al, 1990;Shirato et al, 1995). The likelihood of local relapse is believed to be reduced by the addition of radiotherapy (Przybylski et al, 1997).…”

“…The likelihood of local relapse is believed to be reduced by the addition of radiotherapy (Przybylski et al, 1997). Support for the ef cacy of radiotherapy has come from a retrospective series of pediatric (O'Sullivan et al, 1994), adult (Shirato et al, 1995), or combined patient populations (Chun et al, 1990;Linstadt et al, 1989;Minehan et al, 1995), with long-term survival rates ranging from 40% to 71%. Conversely, there have been similar retrospective series where no survival advantage has been demonstrated with postoperative radiotherapy DeSousa et al, 1979).…”

“…Only 2% to 10% of these tumors are intramedullary spinal cord tumors (Allen et al, 1998;Bouffet et al, 1997;Chun et al, 1990;Constantini et al, 1996;Lowis et al, 1998;Nadkarni and Rekate, 1999;Rossitch et al, 1990;Stiller and Nectoux, 1994). The overall incidence of CNS tumors is approximately 24 to 35 per million in both Australia and the United States (Cokgor et al, 1998;Stiller and Nectoux, 1994).…”