Dear vermontgirl: Scar tissue can feel very hard and the shap can be variable but could feel round. Most of the time scar tissue forms soon after surgery but that's not to say that this couldn't be scar tissue. I think the MRI is a good idea because no matter how confident the doctor is, you will continue to worry. Hopefully, the MRI will clarify this for you.
I would opt for a biopsy, rather than the mri: an image is only an image. Even if it looks ok, a growing hard mass 2 years after treatment needs a diagnosis. I'd consider a core needle biopsy, which your surgeon ought to be able to do easily -- when the lump is feelable, it doesn't need xray localization.
Thank you for helping to decrease my anxiety and I appreciate your straightforward answers!
Vermontgirl, you are right to question...my mother was told by 2 drs. that it was probably just scar tissue also & the recent mammograms did not show conclusive evidence...she too felt it was growing & the 2nd dr. opted for a mastectomy since it was her 4th biopsy & lumpectomy combined in that breast but still insisted "he'd be suprised if it was anything". Well surprise! It was cancerous & she's now diagnosed w/stage III. Be dilegent until YOU feel comfortable w/ the answers. Good Luck!
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