### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
A soft lump appeared overnight on upper chest just below my collar bone. It is about the size of a 50c piece. No pain. Was painting and moving furniture for past 2 days.  Im a female 41 5 6" weight 125 just had mamogram in april results clear. Thank you for any information.

### output:

HI, Dear,Thanks for the query to Chat Doctor.1-I have studied your query in depth.2-IN my opinion, this lump of 50 c size on the upper chest below collar bone is not to be worried, as your recent mammogram is normal.3-This lump could be existing there and was noticed after your exertions 2 days back .3-a-Cause of this lump could be existent fibroadenomas in the upper breast. Exertional stress could have made it noticeable by you.4-So don't worry, as it does not hurt you.4-a-Still I would advise you to keep a watch on it especially before and after the periods.4-b-I would advise you to show your doctor -surgeon, if it hurts or grows more painlessly or with pain.3-Dear, cause of this lump is -fibrogenesis -a hormonal change in the breast, which is painless in most cases and is noticed by the exertional stress in your case.5-If you worry I would advise you to consult an ER Surgeon-doctor, who would rule out the medical causes, and would excise the tumor .7-Hope this would solve you query to your satisfaction.8-Wellcome for more queries to me On Chat Doctor. Thnks once again for your inquisitive query. Have a Good Day.!!