swelling in neck with mcl??

I will try to explain this as best I can. My mother who was diagnosed with Mantle cell Lymphoma over 2 years ago and is still on watch and wait, (no treatment yet).  Just had a check up with her breast cancer doctor 2 weeks ago, which consists of bloodwork and he checks her over. He said all looks good. I have not seen my mother since early August since I live many hours away, however when I got home to visit her on the weekend I could see that her lymph nodes on the right side of her neck are swollen enough that you can see them. She never noticed herself but they are definately much larger than last time I seen her.  I was wondering is this anything to be concerned about? I dont know if they were enlarged at the time of her checkup. She is having no other symptoms. Also can they fluctuate with lymphoma or just contiuosly get larger? She is having another routine checkup with  her lymphoma doctor in November. Is this something that can wait where there are no other symptoms? Any thoughts or previous experiences would be greatly appreciated..