<s>[INST] I am a 21 yr old female and have 2 children I had a normal breast exam 4 months ago but i was doing a breast exam at home yesterday(i usually do not do them) and found a lump on the right breast next to the sternum its about 1/2 in next to the sternum.was wondering if i should be very concerned? [/INST] HiThanks for your query.This is good that you found a lump.Self examination saves many lives and you should do this frequently.As per your history the lumps is of a short duration so the possibility of this having a cancer is very very less and you are young enough. Breast cancers do not occur usually at such an early age. The most probable diagnosis  is fibrocystic disease or fibroadenosis.I would advise you to undergo: MammographyUltrasonographyFNAC- fine needle aspiration cytology to get an accurate diagnosis.Take the medicines as per clinical presentation as seen by a Surgeon or Oncologist </s>