The addition of chemotherapy to immunotherapy is also sometimes preferred for those with rapidly progressive and high-volume disease, even in those with high PD-L1 expression.
However, in large pipelines that can contain enormous volumes of fluid, reversing a pump can be the equivalent of slamming a freight train into a brick wall.
A thousand meters down, the pressure is over 100 times what we experience at the surface, or enough to compress the air in a soccer ball to the size of a ping pong ball — and a half.