What term is used to describe the benign condition that may have caused Ms. Barker's breast mass? What is inside the cysts of fibrocystic breast disease? Mammography and ultrasonography reveal a solid lesion (not cystic). What is the most common type of breast cancer? Biopsy determines that Ms. Barker has invasive carcinoma of the breast. What is the difference between ductal carcinoma in situ and invasive carcinoma of the breast? Ms. Barker's breast cancer has metastasized to her lungs. What is the difference between metastatic lung cancer and primary lung cancer?