Melanocytic Nevus Difference Between A Birthmark Mole And Nevus Stock Illustration Download Image Now iStock Retroflexions.com The Rectal Bleeding Rainbow ORAL MELANOTIC MACULE (OMM) (Also called focal melanosis labial melanotic macule) A benign, localized, flat pigmented lesion of the oral mucosa Caused by a focal increase in melanin production Melanin Magic Natural Awakenings Atlanta Melanocyte Wikipedia GASTROINTESTINAL HEMORRHAGE (2): Melena. Melena, the passage of black, tarry stools, usually implies blood loss greater than 500 ml originating anywhere between the oropharynx and the right hemicolon. Melena occurs most often,