Non-Keratinizing Nasopharyngeal Carcinoma with Adenomatous Differentiation. 
A case of non-keratinizing, EBV-positive (EBER-in situ hybridization), carcinoma with adenomatous differentiation is presented.  The patient is a 40 year old male with T2N2M0 disease who received standard combined chemo- and radiotherapy with complete resolution of all tumor.  The tumor cells were strongly positive for low-molecular weight cytokeratins (AE1-3) and scattered cells expressed cytokeratin 20.  No expression of cytokeratin 5/6, 7, p63, TTF-1, CDX2 or androgen receptor was detected.  There was no evidence of recurrence or disease progression on follow-up after 19 months, which included post treatment MRI and PET-CT scans.