中央为有癌细胞排列于其中的导管。然而，该导管内癌不仅限于导管，还向外浸润至周围间质而成了浸润性导管癌。 In the center is a duct lined by carcinoma cells. However, this ductal carcinoma is not confined to just the duct, but infiltrates outward into the surrounding stroma as an infiltrating ductal carcinoma.