Would you use 6 months (instead of 12 months) of trastuzumab for locally advanced Her-2 positive breast cancer patients?

I would not recommend 6 months of maintenance trastuzumab for higher risk patients, such as one that received neoadjuvant therapy. The PERSEPHONE trial¹ had as its strength its large size and sufficient number of events for a conclusion regarding the population tested (and the diversity of regimens ...

What would you consider as being low risk vs. high risk disease?

I will not use 6 months of trastuzumab among patients with locally advanced breast cancer. As @Dr. First Last stated, while the data from the PERSEPHONE trial presented at ASCO showed non-inferiority between 6 and 12 months, we should wait for the final peer-reviewed manuscript where more informatio...