title: Junctional nevus of the oral mucosa. Light and electron microscopic observations.
abstract: Junctional nevi of the oral mucosa are rare and may be precancerous. A patient who had an enlarging junctional nevus of the labial mucosa with an adjacent lentigo simplex was studied by light and electron microscopy. On the basis of morphologic similarities--dentritic appearance, lack of desmonsomes, proliferative melanin production, and lack of cytoplasmic fibrils--it appears that the nevus cell most likely develops from melanocytes. The reason for the transformation from melanocyte to nevus cell or junctional nevus cell hyperplasia is unknown.
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000368:Aged; D001485:Basement Membrane / Q000648:ultrastructure; D001706:Biopsy; D003593:Cytoplasm / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008048:Lip Neoplasms / Q000175:diagnosis / Q000201:enzymology / Q000473:pathology*; D008247:Lysosomes / Q000648:ultrastructure; D008264:Macrophages / Q000648:ultrastructure; D008543:Melanins; D008544:Melanocytes / Q000648:ultrastructure; D008928:Mitochondria / Q000648:ultrastructure; D014442:Monophenol Monooxygenase / Q000378:metabolism; D009061:Mouth Mucosa / Q000201:enzymology / Q000473:pathology*; D009508:Nevus, Pigmented / Q000175:diagnosis / Q000201:enzymology / Q000473:pathology*; D012270:Ribosomes / Q000648:ultrastructure; D014617:Vacuoles / Q000648:ultrastructure
chemical_list: D008543:Melanins; D014442:Monophenol Monooxygenase; D000135:Acid Phosphatase