Hi Pam, sorry to hear about the possibility of a second neck dissection, but as Gary says, It's not a problem until the biopsy says so.
That being said, I do have a question, did you receive radiation to that area after the first dissection. Sometimes surgeons have a difficult time working with areas that received radiation.
I don't think you'll have that much problem depending on how much tissue the doctor takes. I haven't had a second dissection on the same side, but had dissections on both sides. Second surgery was neck dissection only, and other than being stiff because of the bandages, I didn't have much problems, actually went into the office for a while the day I was released from the hospital.
I would guess there would be some increased numbness in the area, and probably reduced range of motion with that particular arm and shoulder. I would think you would miss about 2 weeks of classes, one week because of surgery and Maybe but not for sure, the second week afterward if there's any other pain from the surgery.
Again every person and every surgery is different, so there may be different outcomes, you may fare better or may have more problems depending on surgeon and how much tissue he takes.
Bob