Mremi, AlexYahaya, JamesAbraham, ZephaniaMwakigonja, Amos2020-11-242020-11-242019Mremi, A., Yahaya, J. J., Abraham, Z. S., & Mwakigonja, A. R. (2019). The role of a minimum immunohistochemical antibody panel in confirming undifferentiated nasopharyngeal carcinoma: A cross-sectional study at the Muhimbili national hospital, Dar-es-Salaam, Tanzania. Nigerian Medical Journal: Journal of the Nigeria Medical Association, 60(6), 279-284.DoI:10.4103/nmj.NMJ_134_19http://hdl.handle.net/20.500.12661/2526Full text article. Also available at http://www.nigeriamedj.com/article.asp?issn=0300-1652;year=2019;volume=60;issue=6;spage=279;epage=284;aulast=MremiIntroduction: Nasopharyngeal carcinoma (NPC) is a malignant epithelial neoplasm arising in the nasopharyngeal mucosa that shows light microscopic and/or ultrastructural evidence of squamous differentiation. Immunohistochemistry (IHC) can be used to reliably distinguish undifferentiated NPC from other malignant tumors, and the technique may be a necessary tool toward the arrival of a definitive diagnosis, particularly when dealing with challenging cases. Materials and Methods: This was a cross‑sectional hospital‑based study which was conducted at Muhimbili National Hospital. The study involved 120 patients with NPC who were diagnosed on histopathological basis between 2009 and 2013. Results: The sensitivity and specificity of hematoxylin and eosin (H and E) stain in diagnosing NPC were 99% and 30.4%, respectively. The accuracy of H and E stain to diagnose NPC and lymphoma was 94.2% and 30.4%, respectively. CD45 antibody helped to confirm 16 cases which were diagnosed as NPC on H and E stain to be lymphoma. Further, AE1/AE3 antibody helped to confirm one case who was diagnosed as rhabdomyosarcoma on H and E stain to be NPC. Conclusions: The sensitivity and accuracy of H and E stains to diagnose NPC were very high whereas the specificity was very low. A significant proportion of previously diagnosed NPC cases by routine H and E stains were confirmed not to be so by a minimal IHC antibody panel of pan‑cytokeratin cocktail (AE1/AE3) and leukocyte common antigen (CD45). This highlights the paramount importance of a minimum IHC panel in assisting to obtain a definitive diagnosis in challenging cases of NPC.enAE1/AE3CD45Nasopharyngeal carcinomaNPCEpithelial neoplasmMalignant epithelial neoplasmLeukocyte common antigenPan‑cytokeratin cocktailArticle