hi @mattydlb. I sorry your dad is going through this. I too had a similar situation. The cancer was found in my lymph nodes in my pelvis area. Based on the cell type (squamous cell) it pointed them in a couple of directs to look and do biopsies. Unfortunately, after many biopsies it was never found and as they monitored the growth of the lymph nodes they decided to treat based on where they thought it should be. Im in Chicago with Northwestern Med (a teaching hospital). My doctor brought my case to the tumor board for boarder discussions with all the experts. I recently had my first scan after treatment and the lymph nodes appear to be normal and no signs of cancer elsewhere. I hope this helps.