My dad just had surgery about two months ago to remove a part of his tongue with a 2cm squamous cell carcinoma mass. They were able to take it all out, but since it was just barely in 2nd stage they went into the lymph nodes- everything came up clear! He just noticed today that there were two very small white bumps right on top of where the main cancer was (on his tongue). He has a docters appointment for tomorrow, but I'm very worried and would like to know what it could be. Wouldn't it be too soon for cancer to show up again? What else could it be?

Thank you