Do I need a biopsy?

My Doctor found two lumps in my breast (one in each).  I'm 30 yrs old and my Mother had advanced breast cancer 2 years ago.  After finding the lumps I had a mammogram and nothing showed up.  I'm scheduled for an ultrasound tommorrow.  If nothing shows up on the ultrasound, do I need a biopsy?  Thank you for an info.

[CCF-RN,MSN-JS]

Dear Kandykay, It's hard to say whether or not it will be necessary at this point.  In a younger woman (< 35) a mammogram may be inconclusive due to the denseness of the breasts.  As we age our breasts have a higher ratio of fat to breast tissue making it easier to detect calcifications that might be an indication of a problem. I don't know if the denseness of your breasts was a factor in the results of your mammogram.  The ultrasound is helpful in determining whether the lumps are solid or cystic (fluid filled).  A biopsy would be more definitive as to whether or not the lumps were cancerous.  When the results are back you will need to discuss with the physician what their interpretations of the results of the testing are, and what will be the recommended next step, based on the findings.