Surgical Outcome and Prognostic Factors of Spinal Intramedullary Ependymomas in Adults

Chang, Ung Kyu; Kim, Hyun Jib; Chung, Chun Kee; Cho, Byung Kyu; Wang, Kyu Chang

Abstract

Ependymoma is the most common spinal intramedullary tumor in adults. The authors reviewed clinical data of 31 patients with spinal ependymoma who underwent operations between 1979 and 1996. The ages of the patients ranged from 15 to 62 years with a mean of 36.9. We analyzed clinical manifestations, radiologic findings, extents of surgical removal, histologic subtypes and follow-up results. Most patients were presented with sensory symptoms as initial symptoms which had lasted for 36.5 months on the average. The most frequent location was conus region(10 cases, 32%) followed by cervical, thoracic and cervico-thoracic spinal level. All cases were divided into two groups histologically, 12 myxopapillary subtypes and 19 non-myxopapillary subtypes. Operative results were dependent on the locations and the histologic subtypes of the tumor. Total removal was achieved in 4 cases out of 10 cases with masses around the conus and in 19 cases out of 21 cases with masses at other regions(p=0.003). Tumors were totally removed in 97% of 19 non-myxopapillary subtypes, but in 42% of 12 myxopapillary subtypes(p=0.001). From the follow-up data, we found that mean progression free interval was 83 months and 5 year progression free rate was 70%. Extent of removal was the only significant prognostic factor on multivariate analysis. Other factors such as tumor location, histologic subtype and radiation therapy were not significant. Disease progression was noted in 2 cases out of 23 cases of total removal group, but in 4 cases out of 8 cases of incomplete removal group (p=0.008). Postoperative radiation therapy was done in 4 cases in incomplete removal group and tumor regrowth was noted more frequently in non-radiation group than in radiation group without statistic significance. We concluded that disease progression can be determined by the extent of removal which is related to the tumor location and histologic subtypes.