Would you still offer trastuzumab deruxtecan in a patient with progressive HR+/HER2+ breast cancer who has prior history of cell cycle inhibitor related pneumonitis?  

In DESTINY-Breast04, about 70% of patients were CDK4/6i treated but were excluded if they had a history of ILD/pneumonitis. So, we don't know if this patient is at higher risk of pneumonitis with trastuzumab deruxtecan. I would consider it if her previous pneumonitis was mild and fully resolved with...

This is a bit of a data free zone, in the clinical trials prior ILD was not allowed. I think banning someone from TDXd when it has a clear survival benefit for any prior ILD may be a disservice to patients. We also have seen data from Rugo etc. that rechallenge among G1 is very appropriate for TDXd ...