Top Line: Do antibody drug conjugates increase the risk of radiation necrosis for patients receiving SRS for brain mets?
The Study: Antibody drug conjugates (ADCs) are increasingly utilized in the treatment of advanced cancer. Their targeted payload is often a potent cytotoxic agent. This retrospective study took a look at outcomes for 98 patients who at some point had been treated with SRS for brain metastases and trastuzumab emtansine (53.1%), trastuzumab deruxtecan (51%), and/or sacituzumab govitecan (26.5%). At 24 months, the cumulative incidence of RN was 8.5%. Receiving an ADC concurrent with SRS (Within 7 days before and 21 days after) was associated with 4 times the risk of developing RN even after controlling for things like brain met volume and prior radiation. Furthermore, the rate of grade 4-5 RN was 7.1% with concurrent ADC compared to 0.7% without. For re-irrradiated lesions, the risk of RN was a whopping 42% with concurrent ADC compared to 9.4% without concurrent ADC. Finally, the authors did not identify a specific ADC that was more strongly associated with RN risk.
TBL: In this retrospective study, receiving an ADC 7 days before to 21 days after SRS for brain metastases increased the risk of radiation necrosis. However, this risk was most prominent for larger and especially re-irradiated lesions. | Lebow, JAMA Oncol 2023
The Study: Antibody drug conjugates (ADCs) are increasingly utilized in the treatment of advanced cancer. Their targeted payload is often a potent cytotoxic agent. This retrospective study took a look at outcomes for 98 patients who at some point had been treated with SRS for brain metastases and trastuzumab emtansine (53.1%), trastuzumab deruxtecan (51%), and/or sacituzumab govitecan (26.5%). At 24 months, the cumulative incidence of RN was 8.5%. Receiving an ADC concurrent with SRS (Within 7 days before and 21 days after) was associated with 4 times the risk of developing RN even after controlling for things like brain met volume and prior radiation. Furthermore, the rate of grade 4-5 RN was 7.1% with concurrent ADC compared to 0.7% without. For re-irrradiated lesions, the risk of RN was a whopping 42% with concurrent ADC compared to 9.4% without concurrent ADC. Finally, the authors did not identify a specific ADC that was more strongly associated with RN risk.
TBL: In this retrospective study, receiving an ADC 7 days before to 21 days after SRS for brain metastases increased the risk of radiation necrosis. However, this risk was most prominent for larger and especially re-irradiated lesions. | Lebow, JAMA Oncol 2023