I too had kidney cancer at the age of 42 and had my left kidney removed. It was about the size of an orange. That was 17 years ago. The doctors put me on a medicine called Megace for two years. This was only as a preventative measure as they called it. I have had many bone and CT scans. The only problem with the scans is that they don't always show what is going on in your body. They did not show either of the following tumors which I found them myself. The doctors said that the CT is only a machine and if the surrounding tissue was very close in match to the tumor the CT could not detect it. They also said it was the best they had to use. About 4 years after surgery I had a secondary tumor removed from my sternam bone and another one developed two years later on my butt and was removed. The doctors said that secondary tumors would continue to grow until removed, but would not spread to other parts of the body only the primary tumor could do that. They also told me that this could happen the rest of my life. So far I have not had any additional tumors. Those cells just seem to float around until they decide to grow.
At the time I found out that I had this cancer, I had one child in middle school and one was getting ready to start high school. I had no idea that I would even see them graduate from high school. They both have now graduated from college, a career, and have families of their own.
Keep a postive attitude, which is very difficult to do, but I believe it is part of the battle to beat this disease.
The more people you talk with you will hear stories of others that have known of someone who also had kidney cancer. Best of luck and pray for a better day.