Hi @chita
To try to put you at ease about your diagnosis. If they have offered you Pembrolizumab they have not only established that your tumour is triple negative, but also that the sample had at least 10% PD-L1 cells in it. PD-L1 binds with PD-1 to make your cancer invisible to your immune system, so your immune system leaves it alone. Pembrolizumab is a PD-1 inhibitor so it breaks that bind and allows your immune system to ‘see’ the cancer. The drug removes PD-1 everywhere, so there can be consequences if your immune system starts attacking other things.
It’s a risk/reward thing. When it works well, it works very well, but can cause other issues. I speak as someone with metastatic PD-L1 positive TNBC. Pembrolizumab has given me (so far) a lasting remission, but also damaged my kidneys, thyroid and lungs. I don’t think I would be here without having had the treatment.