What can cause aching type pain in left side of breast? mammogram in june was clear, but i do have dense tissue?

Breast pain at 60 ?: Over time, and after menopause, extrogen levels have caused increased "fibro-cystic changes " to occur in both breasts. Your breasts are not symmetrical, so the left side may be more sensitive to acquiring dense fibro-cystic tissue than the right. If your family history is positive for breast cancer (mother, sister, grandmother) ask your gyn physician to request an MRI of both sides.