How do you approach treatment of a recurrent low grade glioma several years removed from prior radiotherapy?  

It's hard to tell based on the question, but assuming the patient still has a LGG on recurrence and a high grade transformation hasn't taken place, it can be reasonable to re treat to full dose 45-54 Gy (assuming can meet dose constraints to normal structures). Factors to take into account are IDH m...

I agree with both replies above. Our group has tended to favor fractionated RT courses of 2-2.5Gy to dose of 40-50Gy over 20 to 25 fractions in the re-irradiation setting. Generally the cumulative dose prescription between the 1st and 2nd course is ~100Gy (though there are several clinical nuances t...

This is a nuanced situation, and a lot depends on the extent of the recurrent tumor, the performance status of the patient, and prior treatment. We typically evaluate imaging and, preferably, new pathology to see if it has transformed to a high grade glioma (typically true, per non-believers EORTC t...