Luminal A and Luminal B Types

The luminal types are estrogen receptor-positive, usually low grade, and tend to grow slowly. The gene expression patterns of these cancers are similar to normal cells that line the breast ducts and glands (the lining of a duct or glad is called its lumen). Luminal A cancers have the best prognosis. Luminal B cancers generally grow somewhat faster than the luminal A cancers and their prognosis is not quite as good.