5mm mass on mammo not on ultrasound

Hi I have a question regarding a lump found on mammo.  I went in for a mammo 2 weeks ago. My breast are very lumpy (My mother and 4 out of 5 sisters have this) They said I need to go back for a six mounth follow up on my right breast (fibro grandular tissue) they said not to be concerned, but the found a 5mm lump in my left breat.  They sent me for an ultrasound.  It was negative they couldn't find it.  I am supposed to go to the surgeon on July 11, to discuss the possibility of biopsy.  I am told we will go over the results of both tests and compare.  I have been told it is probably nothing that is was round and smooth on mammo. I am just very concerned I am a 35 year old mother of 4.  Should they do another mammo to make sure it is still there.  Why can't it be seen on ultrasound?  Is this a commom problem? Please try to give me some answers.  Thank You

[CCF-RN,MSN-JS]

Dear lisamw, Different types of tests help to give different information.  A mammogram is an x-ray of the breast tissue,  an ultrasound is use of sound waves to differentiate between solid or fluid filled tissue.  A finding that may be seen on a mammogram is not always seen on an ultrasound.   The findings from both the mammogram as well as ultrasound will be considered by the surgeon and they will use that information as well as physical exam to determine the recommendation for the next step in evaluation.  

[Austinuno]

Ask your Doctor for a PET scan.  If the lump is cancerous it will show on the scan. Lumps as small as 2mm. are found on PET scan. It is an expensive test, state of the art, and your insurance may fight it due to the cost, but is better than mamogram (mammogram) or ultrasound.  Best of luck to you.

[taylor1976]

A related discussion, 5mm solid breast lump was started.