Large and giant petroclival meningiomas: therapeutic strategy and the choice of microsurgical approaches - report of the experience with 41 cases.

OBJECTIVE

To evaluate patients' clinical outcome, survival and performance status at the mild-term follow-up evaluation after optimal microsurgical resection of large and giant petroclival meningiomas (PCMs).

METHODS

During a 4-year period (2004-2008), 41 patients underwent operative procedures for resection of PCMs. The tumour size was large or giant in 100% of the patients, with a mean tumour diameter of 4.4 cm. Tumours extended into adjoining regions in 26 of the patients. Six previously underwent operation or irradiation. Gross tumour resection (GTR) was accomplished in 25 (61.0%) patients, subtotal resection (STR) in 15 (36.6%) patients and partial resection in 1 (2.4%) patient. There were no operative deaths. Postoperative complications (cerebrospinal fluid leakage, quadriparesis, infections, cranial nerve palsies, etc.) were observed in 27 (65.9%) patients. Postoperative radiation or radiosurgery was administered to 6 of the 41 patients who had residual tumours.

RESULTS

At the conclusion of the study, 27 (65.9%) patients were alive with radiological evidence of the residual disease, and 14 (34.1%) patients were alive without radiological evidence of the residual disease. The mean follow-up period was 35 months (range, 15-45 months). Six (14.6%; five of the STR and partially resected patients and one of the total resection patients) had recurrence; of these patients, four underwent repeat resection and two were treated with gamma knife radiosurgery. The Karnofsky Performance Scale score was 78 ± 14 preoperatively, 80 ± 10 at 1 year postoperatively and 81 ± 10 at the time of the latest follow-up evaluation. Common disabilities at the time of the follow-up evaluation included diplopia, facial numbness and swallowing difficulty. Most patients developed coping mechanisms.

CONCLUSIONS

The surgical strategy of large and giant PCMs should be focused on the survival and postoperative quality of life. The good surgical approach should be based on the tumour location, the growth direction, the invasion of adjacent structure, the age of the patients and the experience of neurosurgeons. Selectively pursuing an STR without radiotherapy rather than a GTR is a reasonable strategy. Moreover, microneurosurgical technique plays a key role in the level of tumour resection and preservation of nerve function. Intraoperative electrophysiological monitoring also contributes dramatically to the preservation of the nerve function.