I'm 15 years old and have had this problem 3 times now. I have a small lump under my armpit that itches. It is not a visible lump, but I can feel it when touching my armpit. It comes and goes, well I am sure it does. The itching goes after around 2-3 days and it takes a few months for it to come back, but I never check if the lump goes, which I am now aware that I should. My mum says it is a swollen lymph gland or something along the lines of that, but I'm not completely convinced. I'm only 15 and I hope breast cancer is out of the question, but I'm really worried if it is, so do you have an answer to what this may be? Thank you.