TEST:

PATHWAY antiHer2/neu (4B5) Rabbit Monoclonal Primary Antibody

A4: Currently, the PATHWAY anti-HER2 (4B5) test is the only FDA approved companion diagnostic indicated to identify HER2-low status in patients with metastatic breast cancer. The labs are revalidating their HER2 tests. #HER2low #PathTwitter #BreastPath (@DrBuiPathology)

A4. We did a survey study to identify the most commonly used antibodies, 4B5 came on top, which is the only FDA approved companion diagnostic indicated to identify HER2-low status in patients with metastatic breast cancer. #HER2low #PathTwitter #BreastPath (@DrBuiPathology)

Exactly! Which seems counterintuitive, right? I have some doubts about that HER2 expression classification, and I would love to see the images of HER2 IHC from this trial. Just a reminder: the antibody used to stain HER2 (4B5) is not approved in sarcoma. (@FlaviaMichelini)