I have COPD. One day I got blood on my cough. My doctor order CT scan of my chest and they found nodes, the largest one is about an inch. Then I undergo on Bronchospic procedure, do the washing of my bloody lungs, got sample of the fluids. The fluid comes out negative if any malignant cell. Then my doctor said I need to go for another procedure to get a sample from the largest nodes. My question is, why do I have to go for another procedure, the fluid sample is not malignant? I m confused, please help. Thank you.