Invasive Ductal Carcinoma

Invasive ductal carcinoma (IDC) is a type of breast cancer. It sometimes goes by other names, such as invasive breast cancer, ductal carcinoma, infiltrating breast cancer and infiltrating ductal carcinoma.

According to the American Cancer Society, IDC is the most common type of breast cancer, accounting for nearly 80 percent of new invasive breast cancer cases.

IDC starts within the ducts of the breasts, but will spread to, or "invade," other breast tissue. Some rarer forms of IDC include:

  • Medullary Carcinoma: This infiltrating breast cancer has a rather well-defined boundary between tumor tissue and normal tissue.
  • Metaplastic Carcinoma: Also known as carcinoma with metaplasia, metaplastic carcinoma is a very rare type of invasive ductal cancer that includes cells that are normally not found in the breast, such as cells that look like skin cells or cells that make bone.
  • Mucinous (Colloid) Carcinoma: Also known as colloid carcinoma, this rare type of invasive breast cancer is formed by mucus-producing cancer cells.