Your breast may be larger due to breast lymphedema. After my lumpectomy and sentinel lymph node biopsy, my affected breast was noticeably smaller. Pretty soon, however, I noticed it became bigger, even larger than my other breast. I was seeing a physical therapist to monitor for lymphedema, and she immediately identified breast lymphedema. My breast had a slight orange peel texture that is also a sign of lymphedema. I did have chemo and 33 radiation treatments (28 to the whole breast) but never saw shrinking. With a few, very easy things, I keep the breast lymphedema in check, but my PT has seen women with affected breasts that become gigantic. I’d ask about the possibility of breast lymphedema!