<s>[INST] Good afternoon,I have had an olive size lump/bump on my left collarbone, I want to say for over 5 years now.  Well a couple years ago I asked my gynecologist about it and he said it was nothing to concern myself with.  Now just a week ago my sister had informed me that I should have my doctor look at it cause it could be a lymph node.  I just left the doctors office and he said it was a fatty tissue build up.  This is caused by my bone protecting itself from an injury.  He then proceeded to inform me that this would not be covered by my insurance since it is cosmic procedure.  Im a little skeptical of his diagnosis, what type of doctor would you recommend for me to see regarding this matter? [/INST] Welcome to Chat Doctor .1. Generally most common cause are lymph node enlargement.2. Other causes are Lipomas (fat), Brachial cleft cyst lately identified.3. To confirm the consistency get an ultrasound soft tissue lesion done. It will give exact content and where it is arising from.4. You need to see surgeon appointment. Hope it helps you. Wish you a good health. Anything to ask ? Do not hesitate. Thank you. </s>