title: Immunohistochemical expression of keratins 6, 7, 8, 14, 16, 18, 19, and MNF-116 pancytokeratin in primary and metastatic melanoma of the head and neck.
abstract: OBJECTIVE
  To investigate the immunohistochemical expression (IHCE) of selected keratins in primary cutaneous and mucosal melanoma (pM), and metastatic melanoma (metsM) of the head and neck and to compare their expression to a group of undifferentiated/poorly differentiated tumors of the same anatomic region.
  
  
  METHODS
  IHCE of K6, K7, K8, K14, K16, K18, and K19 were studied in 29 melanomas and 70 cases of non-melanoma tumors of the same anatomic region (neuroendocrine carcinoma, neuroblastoma, olfactory neuroblastoma, sinonasal undifferentiated carcinoma, undifferentiated nasopharyngeal carcinoma, anaplastic large cell lymphoma, poorly differentiated squamous cell carcinoma (PDSCC), and Ewing sarcoma). MNF-116 pancytokeratin was investigated in melanoma.
  
  
  RESULTS
  All studied keratins, except K6, were expressed in melanoma. IHCE of MNF-116, K8, and K18 was higher in metsM compared with pM. K14 and K16 expression was highest in PDSCC.
  
  
  CONCLUSIONS
  metsM expresses keratins more than pM, specifically K8, K18, and MNF-116. Keratin positivity in an undifferentiated or poorly differentiated neoplasm does not necessarily exclude the diagnosis of melanoma.
authors.affiliation: Associate Professor, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan. Electronic address: safadir@ksau-hs.edu.sa.
authors.forename: Rima A
authors.initials: RA
authors.lastname: Safadi
authors.affiliation: Oral Medicine specialist, Ministry of Health, Amman, Jordan.
authors.forename: Dima H
authors.initials: DH
authors.lastname: Bader
authors.affiliation: Consultant Pathologist, King Hussein Cancer Center, Amman, Jordan.
authors.forename: Niveen I
authors.initials: NI
authors.lastname: Abdullah
authors.affiliation: Full Member and Chairman, Pathology and Laboratory Medicine Department, King Hussein Cancer Center, Amman, Jordan.
authors.forename: Maher A
authors.initials: MA
authors.lastname: Sughayer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D005260:Female; D006258:Head and Neck Neoplasms / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D007633:Keratins / Q000378:metabolism*; D008297:Male; D008545:Melanoma / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged
chemical_list: D014408:Biomarkers, Tumor; D007633:Keratins