Tumors are usually small because they come to clinical attention early on in development, with an average size of about 1.6 cm. There is a very characteristic appearance to the tumor when reviewed histologically. A hematoxylin and eosin stained slide of<unk>  showing large canaliculi There is a<unk>  pattern with cords and ribbons showing connection points between opposing columnar cells within spaces that is called a "string of pearls" appearance. A hematoxylin and eosin stained slide of<unk>  showing beading There are often small luminal squamous balls or morules. There is a very well developed supporting tissue that is a loose, fibrillar stroma, rich in hyaluronic acid and chondroitin sulphate. In a few cases small calcifications or microliths may be present. Although seldom necessary, a pathologist can do immunohistochemistry studies to confirm the diagnosis, with the cells strongly reactive with pancytokeratin, S100 protein and SOX10, with a delicate GFAP reaction around the periphery. Even though it is a benign tumor, it must be separated from a basal cell<unk> , pleomorphic<unk> , adenoid cystic carcinoma, and polymorphous<unk> rcinoma.
Canalicular adenoma
Hidrocystoma
Choroidal fissure cyst
Pineal gland cyst
Ischiopatellar dysplasia
Vitreous bulge
Spiradenoma
Paradental cyst