How Much Fluid Should You Send for Cytology?

I wanted to ask you and get your input though. I've read different opinions about how much fluid we should be sending for cytology. It's malignant pleurofusions on your differential. And I'm wondering if you can comment on the sensitivity of cytology for detecting a malignant Pleurofusion. And then, and the second question is in practice, how much do you usually tell your trainees how much fluid they should send to the lab specifically for cytology? Sure. Thanks so much, Dave.