Hello. My grandmother (88) was diagnosed with stage 4 lung cancer 10 days ago. I am trying to help her and my parents make decisions. She has a tumor in her right lung and the doctor says that cancer cells are present in the fluid in her lung (which makes the stage 4). No other cancer is present in her body. I have a question about molecular testing. Her results came back negative for mutations. But, she did not have a biopsy of a solid tumor. The "fluid" was used to run the test. And, the test results came back in 1 week. Should I be concerned this was not run properly?