Just an additional note ..... calcifications are NOT tumors; they are tiny bits of calcium that are deposited within the breast tissue. As Zouzi stated they are harmless when scattered about; when they are observed in groups or clusters they may be an indication of something serious but this is NOT always true. Many biopsies done for calcifications return a negative result. I'm sure if further investigation is needed, it will be recommended by your Physician. Regards ....
Fibroid breast tumors or Fibroadenomas are the most common types of breast lumps that occur in women especially in their 20s or 30s and they are benign in nature (Not cancer) and are usually left alone but could be surgically removed if they cause excessive pain.
The doctor will occasionally monitor these lumps to see if they change or grow.
You don't say what your doctor has recommended concerning the Microcalcifications which are quite normal in breast tissue and they are not harmful.However,if they are clustered (grouped) they become suspicious because they sometimes cluster around a mass.
Sorry,but this is all I can tell you with the little information you have given us.