Does anyone know if Lung Cancer causes fluid in the lungs to fill up? My FIL has been experiencing pain in his chest and pain when breathing. They did a chest Xray and numerous other test to try and see what was wrong. The only thing they were able to find was fluid that was in his left lung (th right lung is fine). They drained about a quart out last week and then within a matter of days, it filled up to a higher level. They are testing the fluid now to see what could possibly be causing the problem. Does anyone know if this could be cancer? I should add that he had bloodwork done and had his liver and heart tested and everything was normal.

I would ask the Dr's about a chest x-ray and possible cat scan also. It could be pneomonia, an infection, congestive heart failure Ive heard can cause lungs to fill. Just because blood work comes back "normal" doesnt mean it isnt cancer. I would have the dr do a more aggressive approach to the problem and maybe start "looking" for cancer.

There are 5 major reasons people get a pleural effussion, like the previous post says Congestive heart failure, Pneumonia, infection, add to that Trauma and cancer ( malignant pleural effussion) . My mom had no health issues and developed a pleural effussion which was malignant.Blood work would not show cancer but the fluid they drained out would have cancer cells in it. My mom's effussion came back 3 times always within a week of having it drained so she had a chest tube pleurodesis done which was successful and she has had no more effussions.

Thanks for the posts. I guess they have since tested the fluid for cancer cells and they said it didn't show any. They also said that they don't think it is his heart. In addition, since the fluid is clear, they don't think it is an infection. I don't think they have a clue why it is happening. Now they are talking about going in and getting a sample of tissue or something. I am not sure what that is all about. It is strange why it is continuing to fill.