My father was a smoker. He has been diagnosed with non small cell lung cancer. The doctor is saying that he is in stage 4 and started chemotherapy .My father is a patient of COPD and bronchopneumonia also. His weight has become 35 kgs which was 6 months before. He was being unable to take any food for last six months due to loss of appetite and has become bed ridden. But after the 1st chemo he has started improving. Now he is walking, doing little works and eating sufficient amount of foods. Is he really in stage 4? Or currently in honeymoon period? Is there any hope for his long term survival. His Complete blood count, urea creatinine, and Echocardiography reports are normal.