I am 43 years old and have a 1 cm left breast mass. My doctor says I need a needle biopsy. Is this necessary?

Women who have a mass often need to undergo a breast biopsy. There are many types of breast biopsy procedures for women who have a breast mass.  It is impossible to tell if a mass is a cancer just by examining the breast with the hands. The only definitive way to confirm a cancer is to perform a breast biopsy and send the tissue to the pathologist for examination. In your case, a needle biopsy is fine.