Dear Brian,
My dad had kidney cancer in '91, was removed and didn't have any methastasis so he did not need any tretman. It became methastatic in 2004!!! This means that it has waited somewhere for 13 years to come back, and he had check ups every year. What I would sugest you to find a good radiologist to get second opinion on this noduls in lungs. This is your right as pacient and you owe it to your self. Not everione is good in reading the ct scan. Maybe it's nothing but what if??? This is a battle you can not afored to lose, so ask for another opinion. My dad's methastasis showed after 13 years and it the mean time he was in perfect health, and the first of them came on lungs. I don't write this to scare you, just to make a little more efort.6 month's is long period for waiting with this suspect, so just do it!
Best luck, ana