@dansup I don't know if this will help ease your mind. Our dog Lucy has a few lumps on her, the vet checked them out and said as dogs get older the get lumps nothing to worry about.
she is like 17 years old, I too would be lost without her, and I know when the day comes it will hit me like a tone of bricks but I have to remember all the good times we share together.
They are family members, just give your boy a big hug and lots of treats.