True about cholesteatoma is/are:
Ans. D Erodes the bone Normally middle ear is not lined by keratinising squamous epithelium. If keratinising squamous epithelium is present anywhere in the middle ear or mastoid, it is called as cholesteatoma. The term cholesteatoma literally means - "Skin in the wrong place." It is a misnomer because neither it contains cholesterol crystals nor it is a tumor." Cholesteatoma has 2 pas: Matrix: made of keratinising squamous epithelium.? Central white mass - made of keratin debris. Hence also k/a epidermosis or keratoma - Cholesteatoma has the propey to destroy bones (due to the various enzymes released by it and not by pressure necrosis).
It is a benign tumour
Metastasizes to lymphnode
Contains cholesterol
Erodes the bone