What is the definition or description of: medullary carcinoma?

Soft tumor: “medulla” refers to soft structure of marrow (tumors are often soft) can be found in multiple organs and tissues like, thyroid gland, breast, kidneys, colon, pancreas.

Rare breast cancer: Medullary carcinoma of the breast represents a small proportion of breast cancers (3-5%). These tumors are typicaly larger, of higher grade, and are usually hormone receptor negative--all of which are poor signs in general--when compared to standard ductal carcinoma of the breast. Nevertheless, medullary carcinoma of the breast has relatively good rates of survvial relative to ductal cancers.