Needle biopsy vs. surgical biopsy and breastfeeding

My wife has a small lump in her left breast.  Ultrasound and Mammagram have been inconclusive.  Her Dr. suggested a biopsy just to be safe.  He wants to do surgery to remove the whole lump.  My wife is apprehensive about this.  She's been breasfeeding now for about 6 years and plans to continue.  My questions would be this....1. Is this lump likely due to breastfeeding/milk ducts etc.  2. She would rather have a needle biopsy...what are pro's/con's of both?  3. How will surgical biopsy affect breastfeeding?  

The surgery is scheduled for next week, so any help/advice would be greatly appreciated.  Maybe info on my wife would help...she's 33, not very active, no history of breast cancer in her family.  Thanks in advance!!

Bryan

[CCF-RN,MSN-rf]

Dear bugsdad:  If the lump can be felt, a needle biopsy can technically be done.  However, a needle biopsy is just that, only the cells in the needle can be analyzed.  The cells next to them remain an unknown.  An excisional biopsy removes and examines the entire lump, eliminating the unknown - and often the worry associated with that.  Whether and what type of biopsy depends upon the index of suspicion of the physician in concert with the results of the scans.  She should have a discussion with her doctor regarding breastfeeding and whether there is a recommendation preoperatively.  Technically, a biopsy would not affect breastfeeding (other than being sore).  It may be worth considering any medications that may pass through the breast milk to the recipient.

[surgeon]

it sometimes occurs that milk will leak through the biopsy site and not stop until breast feeding is discontinued. That's not very common, but is a consideration. A core biopsy, which takes more tissue than a fine-needle and is therefore more reliable diagnostically, might be an option.