We have a history of breast cancer in our family, most recently my mother last year, my sister has had a 4 mil. size lump in her armpit and she said it is really painful. She went to a doctor about 4 weeks ago who put her on a antibiotic saying he thought it was swollen lymph node. Not feeling satified with what he said and the lack of consern knowing the history of breast cancer in our family she went to get another opinion. She met with the doctor this week after having a mammogram and the lump has grown from 4 mil. to 7 mil. Her doctor is requesting a consultation with another doctor for a biopsy because of the history in my family of breast cancer. My question is, besides posibly, worst case, breast cancer, what other things could the lump be?