Hi Heather,
Unfortunately we have something in common. My husband was also diagnosed due to Vena Cava Syndrome. He had a pressure in his head and went to the doctor. Due to our primary doctor being very aggressive and going past the schedulers, we had the CT, biopsy, and radiation started within 24 hours! Once the pressure was relieved he felt much better. The body is an amazing thing, the blood will find new paths back to the heart.
We were also told to go and get our affairs in order, take a trip or do whatever we wanted to do. Our doctor said, "If I told you that you had 2 weeks to live what would you want to do?" Like you father, my husband also decided he could prove the doctor wrong. He went through three different chemo therapies with some success and was later put on Iressa. His tumor is shrinking with the Iressa and he feels pretty well now.
He was diagnosed in June of last year and he was only given 4 months. Your dad is right there is hope, many people on this board have been living with their cancer for a long time, and others are cancer free.