Conundrum of 3N: nasopharyngeal nonkeratinizing non-viral carcinoma-reappraisal of fusions and report of two consecutive cases with unusual molecular findings.

Nasopharyngeal carcinoma (NPC) has a unique and complex etiology that is not completely understood. NPC genome has been scrutinized by molecular studies, but small biopsy material and heavy infiltration of nonmalignant cells present major technical challenges. Over the past decade, significant progress in sinonasal tumor taxonomy has taken place with the discovery of tumor-specific fusion oncogenes generated by chromosomal translocation information. We report two consecutive nonviral-associated nonkeratinizing NPCs and their integrated morphological, phenotypical, and molecular characterization, with emphasis on fusions. Both NPCs harbored individual fusions, YAP1::MAML2 and FGFR3::TACC3,respectively.