Discriminating radiation necrosis events from recurrences after fractionated stereo- tactic radiotherapy or single-session stereotactic radiosurgery is a major point in the management of brain metastases. An erroneous diagnosis could lead to either un- necessary invasive actions and counterproductive treatments when RN is confused with recurrences or delays in treatments in the opposite situation. In 2023, a study (https://doi.org/10.1093/noajnl/vdac179) identified a simple and interpretable imaging biomarker with discriminatory power between both conditions.

Now, MOLAB researchers have complemented that biomarker with another two clinical variables adding predictive power and constructed a classifier that has been validated in an independent cohort of patients. 

The calculator requires only longitudinal imaging data (diameters or volumes of the lesions), the primary tumor histology and the type of radiation treatment received and provide a probability that the observed growth is a radiation necrosis event. It can be accessed and used at 

https://radiationnecrosiscalculator.com