A total of 119 consecutive patients (2004–2013) receiving primary surgical treatment for a meningioma in proximity to a venous structure were included. The patients were assessed retrospectively, with a focus on retreatments and mortality. Radicality of initial tumor surgery was scored using postoperative magnetic resonance imaging. Three subgroups were identified: 1) radical total resection (RTR); 2) near-total resection (NTR), followed by aSRS (NTR + aSRS); and 3) NTR but no aSRS (NTR − aSRS). In the NTR − aSRS group, intervention was initiated after radiologic (magnetic resonance imaging) findings verified growth of residual tumor, in contrast to the NTR + aSRS group, which received aSRS before regrowth. Time to first retreatment, progression-free survival (PFS), and overall survival were analyzed with the log-rank test and multiple-events Cox regression.
RTR was associated with the best prognosis. The patients in the NTR + aSRS group had significantly longer time to first retreatment compared with NTR − aSRS patients (P < 0.001). There was also a significant difference in mortality (P < 0.05) and a tendency to prolonged PFS (P = 0.07) in the NTR + aSRS group. The Cox regressions confirmed the positive effects of NTR + aSRS on time to retreatment (hazard ratio, 7.3; P < 0.01) and PFS (hazard ratio, 3.69; P = 0.055).
aSRS of meningioma residuals had a positive effect on tumor control and should be considered in patients with meningioma residuals.