Survival rates in patients with low-grade glioma after intraoperative magnetic resonance image guidance

BACKGROUND: No age-adjusted or histologic-adjusted assessments of the association between extent of resection and risk of either recurrence or death exist for neurosurgical patients who undergo resection of low-grade glioma using intraoperative magnetic resonance image (MRI) guidance. METHODS: The current data included 156 patients who underwent surgical resection of a unifocal, supratentorial, low-grade glioma in the MRI suite at Brigham and Women's Hospital between January 1, 1997, and January 31, 2003. Estimates of disease-free and overall survival probabilities were calculated using Kaplan-Meier methodology. The association between extent of resection and these probabilities was measured using a Cox proportional hazards model. Observed death rates were compared with the expected death rate using age-specific and histologic-specific survival rates obtained from the Surveillance, Epidemiology, and End Results Registry. RESULTS: Patients who underwent subtotal resection were at 1.4 times the risk of disease recurrence (95% confidence interval [95% CI], 0.7-3.1) and at 4.9 times the risk of death (95% CI, 0.61-40.0) relative to patients who underwent gross total resection. The 1-year, 2-year, and 5-year age-adjusted and histologic-adjusted death rates for patients who underwent surgical resection using intraoperative MRI guidance were 1.9% (95% CI, 0.3-4.2%), 3.6% (95% CI, 0.4-6.7%), and 17.6% (95% CI, 5.9-29.3%), respectively: significantly lower than the rates reported using national data bases. CONCLUSIONS: The data from the current study suggested a possible association between surgical resection and survival for neurosurgical patients who underwent surgery for low-grade glioma under intraoperative MRI guidance. Further study within the context of a large, prospective, population-based project will be needed to confirm these findings.