This image shows high-grade adenoid cystic carcinoma (AdCC) of breast. The tumor consists of anastomosing cords and trabeculae of basophilic cells in a background of dense eosinophilic amyloid-like stroma. Some authors have suggested stratification of AdCC into 3 grades based on the relative proportion of the solid component: Grade I, no solid elements; Grade II, solid areas <30%; Grade III, solid areas >30% of the tumor. Grade II and III tumors have been found to be larger and more likely to recur in some studies. However, the relationship of tumor grade to prognosis is controversial.