@Fernweh, I had lumpectomies in both breasts, but only because they told me I didn't need a mastectomy in either. But if I was told I needed a mastectomy in one breast I was saying I would want both removed, that was before I knew what was required, but the surgeon would have taken both off he said if that is what I wanted. I used to be small breasted, in my younger days, but because I am now large breasted I really wouldn't have wanted to be lopsided or weighed down on one side, that was my main reasoning behind having them both off if only one needed to go.
Each person and case is different, but I had strong feelings about what I would have wanted, and that was and still is not to be lopsided, I have enough back issues as it is. All the best and when we know our own reasons for wanting the DMX it will be the correct decision for you. I wish you all the best. xo