I think if anything I'd only give the courtesy to call and let them know I wasn't going to keep the appt... I mean, I love doctors with a sense of humor so long as they still take my symptoms seriously. But I would also look for another doctor if your symptoms are hindering your day to day. Somehow I doubt you'd be upset if your 'serious' symptoms was the occasional headache, or tingly in your pinky... So definitely look for another doctor.

There isn't much of anything that can be done for MS, no matter the sort, but many of the symptoms can be treated.