Prognostic significance of transdural invasion of cranial base malignancies in patients undergoing cranicifacial resection

OBJECTIVE: Invasion of the brain and/or dura is a known negative prognostic factor for patients undergoing craniofacial resection for cranial base malignancy. However, an evaluation of factors that may affect prognosis in this patient subgroup has not been undertaken. METHODS: Between 1993 and 2003, 212 patients underwent craniofacial resection for primary malignancy of the cranial base at the University of Texas M.D. Anderson Cancer Center. Twenty-eight patients (eight women, 20 men; median age, 52 yr; age range, 26-76 yr) had evidence of transdural spread (subdural tumor or brain invasion) of malignancy. These patients were identified and a retrospective review of prospectively collected data was undertaken. RESULTS: Subdural tumors were found in 16 of these patients, and brain invasion was detected in 12. Gross total resections were achieved in 22 patients: 13 with microscopically negative margins, eight with positive margins, and one with unspecified margins. Surgical complications occurred in six patients. There was no surgical mortality. The 5-year actuarial overall survival (OS) was 58%. Eleven patients had no evidence of disease, 11 died of disease, and six were alive with disease at the end of the follow-up period. The median actuarial progression-free survival (PFS) was 38 months (95% confidence interval, 4-72 mo). Gross total resection with negative margins was the key positive predictor of OS and PFS. Brain invasion was a negative predictor of survival (significant for PFS; trend only for OS). There was a trend for shorter OS and PFS in patients with high-grade tumors. CONCLUSION: Overall OS and PFS in highly selected patients with transdural invasion of cranial base malignancy is similar to what has been historically reported for patients without such invasion. The most important variables positively affecting OS and PFS seem to be the ability to achieve a microscopically margins-negative resection followed by absence of brain invasion. Performing this resection in a piecemeal fashion does not seem to affect survival outcomes.