microcalcifications

What would cause clusters of microcalcifications besides cancer?  I have several and they are all in the same plane that would correspond to a duct.  I am awaiting an excisional biopsy in the coming week.  Does DCIS cause discomfort in the breast?  I have had an aching feeling in that breast for some time that I have dismissed.  
Thank you.

[katfox]

I learned that these calcifications can dedvelop from an injury.

BUT biopsy anyway.  Mine looked normal and I still insisted on a biopsy and ended up it was DCIS.

Calcifications do NOT cause any pain...and unless it is a lump only DIGITAL mammograms will detect it.

[mindy888]

Thank you for your response. The radiologist who looked at my mammogram said I had DCIS so I am preparing for that diagnosis when I have my biopsy.  
Did you have lumpectomy or mastectomy?  Or aditional treatment with radiation?  
Thank you.