What factors do you use to determine whether an enlarging lesion after SRS is radionecrosis versus progression?

This is a challenging issue, especially in a community setting where patients had not been treated with SRS before, and radiologists are now confronted with post SRS scans.

The two major things that clinicians can look at are:

1) T2 - T1 mismatch - if there is a correspondence between the contrast-en...