Patient outcome at long-term follow-up after aggressive microsurgical resection of cranial base chondrosarcomas.

Objective: To evaluate patient clinical outcome and survival at long-term follow-up after aggressive microsurgical resection of chondrosarcomas of the cranial base.

Methods: Over a 20-year period, 47 patients underwent 72 operative procedures for resection of cranial base chondrosarcomas. Thirty-three patients were previously untreated, whereas 14 patients previously had undergone surgery or radiation. Twenty-three patients had a single operation and 24 underwent staged (more than one) operations because of extensive disease. Patients who underwent subtotal resection also underwent radiotherapy or radiosurgery. Patients were evaluated at follow-up clinically and by imaging studies.

Results: Gross total resection was accomplished in 29 (61.7%) patients, and subtotal resection was accomplished in 18 patients (38.3%). The resection was better in patients who underwent a primary operation (gross total resection, 68.8 versus 46.7%) rather than a reoperation. Patients who underwent incomplete resection underwent postoperative radiotherapy, which included proton beam radiotherapy (15.6%), radiosurgery (68%), and fractionated radiation (15.6%). There were no operative deaths. Postoperative complications (cerebrospinal fluid leakage, quadriparesis, infections, cranial nerve palsies, etc.) were observed in 10 patients (18%). The follow-up ranged from 2 to 255 months, with an average of 86 months. At the conclusion of study, 36 (76.6%) patients were alive, and 21 (44.7%) patients were alive without disease. Recurrence-free survival was 32% at 10 years in all patients, 42.3% in primary patients and 13.8% in those who underwent reoperation. The Karnofsky performance score was 82.4 +/- 9.8 before surgery, 85 +/- 12.5 at 1 year after surgery, and 85.3 +/- 5.8 at the latest follow-up. Two patients died as a result of radiotherapy complications (malignancy, radiation necrosis).

Conclusion: Cranial base chondrosarcomas can be managed well by complete surgical resection or by a combination of surgery and radiotherapy. The study cannot comment about the efficacy of radiotherapy. Approximately half of the patients survived without recurrence at long-term follow-up (>132 mo). The functional status of the surviving patients was excellent at follow-up.