DEAR MAYO CLINIC: I understand surgery is often included as part of the treatment plan for breast cancer. If I’m a candidate for lumpectomy but am also considering a mastectomy, what are some things I should keep in mind? Should my breast density be a factor in my decision-making? ANSWER: Women diagnosed with breast cancer are almost immediately confronted with treatment decisions. If your surgical oncologist gave you a choice between a lumpectomy and a mastectomy to…