E

These tumors are polyp-like growths with a narrow base or a stalk. Some are nodular overgrowths secondary to inflammation but others are benign or malignant cancers of the glands found in this area. Most are from the specialized sweat (ceruminous) glands of the ear. These glands produce watery secretion (cerumen) that keeps the ear moist. A few tumors arise from the sebaceous glands that produce an oily secretion and a few originate from the surface epithelium (squamous cell carcinomas). Malignant tumors may spread to other parts of the body.

Melanocytes are cells that produce a pigment called melanin. They are found in many parts of the body where there is pigment, particularly the skin, hair and eyes. In embryonic development, melanocytes are related to cells of the nervous system. Melanogenesis (formation of melanin) is a complex process with genetic, hormonal and ultraviolet (UV) control. A suntan is the result of stimulation of these cells by sunlight (UVA and UVB). Inside the eye melanocytes are found in the iris and choroid layers (see diagram).