lung cancer vs emphysema

can anyone help me with this. I have someone who was diagnosed with prostate ca after "waitful watching" of a tumor for 7 years. There have been no other testing done except for the biopsy. Recently a chest xray was done and came back abnormal, however he was dx with early emphysema. My question is.... could this possibly be lung cancer misdiagnosed as emphysema? Just wondering what everyone elses thoughts on this. Thanks!