Once a patient has received a definitive diagnosis of SCC, it is unlikely that any other head and neck areas would be missed. In order to determine that there is cervical node involvement (as they have) they would have had to do an MRI or at least a CT scan to determine this. That scan would have revealed any nodes such and those in the sub mandibular and lingual regions that would have been involved. Palpation of nodes only identifies suspect areas, and no doctor can tell from feeling that something is cancer, only that it is hard, firm, or fixated, all indications that something is out of the ordinary. Then after this initial screening by touch, the scans are done to see what's what. It stands to reason that if they have done the head and neck scans, in this area things are located and identified. An endoscope would allow visualization of anything that is visible on the surface, but would be useless compared to an MRI in identifying underlying cancer.

If you want to be sure of other things, the only risk area left to look for is metastasis past the cervical nodes in the aero digestive tract, the most likely location of a metastasis. Prudence would dictate a spiral CT scan of the lungs early in the process to confirm that things are limited to the head and neck region. Nothing would be worse than wining the battle against an oral cancer only to find after it all, that lung cancer is in the picture....