Quantitative dynamic susceptibility contrast perfusion-weighted imaging-guided customized gamma knife re-irradiation of recurrent high-grade gliomas.

ABSTRACT

INTRODUCTION: Treatment of recurrent high-grade gliomas (rHGG) has always been challenging. This study aimed to explore the treatment effect of quantitative dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI)-guided gamma knife radiosurgery (GKRS) on rHGG. METHODS: Between April 2014 and July 2016, 26 consecutive patients were treated by quantitative DSC-PWI-guided GKRS as salvage treatment for rHGG. The gross tumor volume (GTV) was defined as the high perfusion area on absolute cerebral blood volume maps, with a cutoff value of 22 ml/100 g. The clinical target volume (CTV) encompassed the GTV by 3 mm. Overall survival (OS) and progression-free survival (PFS) were calculated by the Kaplan-Meier method. Prognostic factors were tested by the log-rank (Mantel-Cox) test. RESULTS: With a median follow-up of 32 months, the median PFS after GKRS was 8 months (95% CI [6, 12]); the 1- and 2-year survival rates were 30.8 and 11.5%, respectively. The median OS was 25.5 months (95% CI [18, 40]); the 1- and 2-year survival rates were 96.2 and 57.7%, respectively. Pathology grade and CTV were identified as prognostic factors for PFS. However, none of the parameters tested were independent prognostic factors for OS among these selected patients. No severe radiotoxicity was observed among all patients. CONCLUSIONS: Quantitative DSC-PWI-guided GKRS is feasible for the treatment of rHGG and that these outcomes remain to be validated. Despite this, we think that carefully selected patients can benefit from this treatment method.