The management of metastatic spinal cord compression: a radiotherapeutic success ceiling.
PURPOSE: In assessing the effectiveness of the management of metastatic spinal cord or cauda equina compression, we performed a retrospective analysis of 70 patients with this complication whom we treated from 1985 to 1989. METHODS AND MATERIALS: The most frequent primary diagnoses in our series were carcinomas of unknown origin and of the breast, lymphoproliferative disease, lung cancer, and prostatic carcinoma. We used the Findlay classification to group all patients according to their pre-therapeutic functional motor status as Grade I (24 patients or 34%), Grade II (27, or 39%) or Grade III (19 or 27%). Treatment consisted of 30-45 Gy of irradiation (using two different schedules) together with high-dose dexamethasone; in only five cases was there surgical intervention. RESULTS: We found that a powerful predictor of response to radiotherapy was the patient's neurologic status (Findlay grade) at the time of diagnosis: 66% of previously ambulatory patients remained so, whereas 30% of non-ambulatory patients and only 16% of paraplegic patients regained the ability to walk. Another important predictor of response was primary tumor histology, with the most favorable responses to radiation therapy having been observed in lymphoproliferative diseases and in breast cancer, but with some response in other radiosensitive malignancies as well. CONCLUSION: The similarity of our results to those of other centers leads us to conclude that a radiotherapeutic success ceiling of 80% may have been reached for Findlay Grade I patients with metastatic spinal cord compression. In view of this, we suggest that future therapeutic endeavour would be best directed toward early diagnosis of the condition.