Paucilymphoid non-keratinizing nasopharyngeal carcinoma with prominent stromal desmoplasia--an unusual case reported with brief comments on uncommon histological variants.

We present a case of de novo non-keratinizing carcinoma of the nasopharynx (NK-NPC) with an unusual combination of histological features; (1) a minimal associated component of reactive lymphoplasmacytic cells and (2) a prominent desmoplastic stromal response. Apart from the unusual histologic features, this case did not display any unusual clinical or radiological features. On immunohistochemistry the tumor cells were strongly positive for cy-tokeratins (AE1-3 and 5/6) and p63 and there was strong and diffuse nuclear positivity for EBV on in situ hybridization. Since no external factor could be attributed to the conspicuous paucity of associated lymphoid cells, we feel that this may be due to inherent features of the neoplasm itself. This case highlights the histomorphological variability of NK-NPC. Awareness of the histological spectrum of NK-NPC is important in clinical practice and this is not always adequately highlighted in currently used standard textbooks of head and neck pathology.