In my opinion cancer is cancer - anything size wise that is under 2 cm is considered stage one. 1- 3mm depth isn't huge - but there are people here who have had a 1mm depth, been stage one - and still had one lymph node involved with ECE ( extra capular extension ) which is a little cancer outside the node. This is usually a call for radiation and chemo... Is the small area classified as a tumor? I'm thinking yes. If it has a depth and width - yes... It's a small one but a tumor none the less... And yes I believe a scan is important. If you don't have one - do yourself a favor and keep a close eye on your mouth and neck. I don't want to scare you... But this cancer can be aggressive - so keep an eye on it... Better safe than sorry. My results read much the same way as yours - dysplasia and bits of scc. A fair portion of the underside of my tongue had dyslasia. It was all removed. Clear margins are good -we all hope for them post surgery. The problem with cancer is the margins could be clear - no problem, but there could still be a few cells in a lymph node or elsewhere this is why it is important to keep a close eye on your neck and mouth - and - yes follow up every three months just to be safe. Also apparently Sloan lketterling is one of the best.- Best of luck.