Adenoid Cystic CA
The cribriform areas are almost always present, even if focally, in adenoid cystic carcinoma. They consist of variable-sized, smooth contoured lobules or islands of uniform basaloid cells punctuated by round rigid gland-like spaces. These spaces are not true glandular lumens but represent stromal invaginations (pseudocysts). They are filled with eosinophilic material (PAS-positive, diastase-resistant; reduplicated basal lamina) or basophilic myxoid mucinous material (Alcian blue positive).