In ADH it is the standard of care to do an excisional biopsy because in 20% of the cases, there is sometimes ductal cancer in situ (none invasive), or invasive cells in the adjacent tissue.
The studies indicate that some of
the time some of
the ADH cells may progress to DCIS, etc.
The odds are in our favor. I am told that if all they find is ADH, depending on your personal risks and extent of ADH, more frequent clinical exams and mamms may be all that is needed.