Hi Again. I just thought that I'd update the thread. I saw the ENT yesterday and he wasn't particularly worried about the lesion. He said that it was probably a mucocele, which was more or less what I had come to expect based on a week of googling photos. He gave me the option of having it removed (on a subsequent appointment) which I accepted and that will happen next week.

One thing that did strike me a little bit strangely was that he didn't even palpitate the lesion. He just had me hold back my lip so that he could look at it with what I assume was a large microscope hanging from the ceiling. But maybe that's normal. In any event, I left the office feeling pretty relieved.

Thanks again to everyone and I wish you all the best of luck.