When is it necessary to obtain a postbiopsy mammogram shortly after a successful excisional biopsy in a patient who is planning to have breast conservation?
If the malignancy was associated with calcifications on the mammogram, a postbiopsy mammogram should be obtained to ensure that all the suspicious microcalcifications have been removed. If there are residual calcifications, the likelihood that there is residual disease is quite high. The inverse is not true. If there are no residual calcifications, this does not indicate that there is no residual disease. There may be portions of the cancer that are not calcified. The decision to re-excise is also based on histopathologic margin status.
For breast cancers that manifest as a mass on the mammogram, a postbiopsy mammogram is not needed. The decision to re-excise should be based on the histopathologic margins. Due to the postbiopsy changes in the surgical bed, it would be difficult to differentiate between postbiopsy changes and residual tumor.