Thank you for your comments. I am going for a 2nd opinion today on whether the surgical biopsy is necessary. The biopsy is scheduled for next Friday. It was very good to hear from someone in a similar situation.
I had a large surgical biopsy because I had a large area of DCIS (precancerous cells) and small breasts. When my result came back that the margins were still not clear, I opted for a mastectomy. After the mastectomy we found a small tumor (5mm) amongst the DCIS. It had an aggressive gene and so I had chemo and opted for a second mastectomy (preventative) after I finished treatments a little over a year later.
To be frank, after the biopsy and even the first mastectomy, no one looking at me dressed could see that I had lost 1/2 my breast or even missed my whole breast. We who have smaller breasts can hide it well.
The main thing is to get diseased tissue out of your body. Much can be done to help you achieve the look you want afterward. I have chosen to not have reconstruction, nor to wear prosthetics. I am enjoying going braless and so far, no one has remarked on my flat chest - because it looks almost the same as before. Take care of your health first and then you can do any of several things to achieve the appearance you wish. I am thinking of you.
I would fight any insurance company that says I could not have reconstruction if the lumpectomy is disfiguring.
It sounds like you're having a lumpectomy instead of a biopsy. Get a clear description in writing what they are telling you.
My biopsy was done with a mere core needle. Best wishes