My father is having the following symptoms......Extreme fatigue, extreme loss of appetite, bowel habits have changed from 1 BM a day to several diarrhea stools per day, chronic coughing daily, frothy white sputum, shortness of air with any level of activity, lower back and hip pain. He is a smoker and has been since he was a teenager. He is now 67 years old. He had a chest xray last year, but nothing was seen. His father passed of complications from leukemia. His mother passed of natural age causes. His physician has not been very aggressive in trying to find a cause for his symptoms. Just looking for some advice and a possible direction to start looking in. Thanks for your time!