Aggressive sinonasal natural killer/T-cell lymphoma mimicking refractory sinusitis in a 4-year-old boy.

Pediatric patients with nasal symptoms are common, and most of them usually have inflammatory diseases, such as sinusitis, chronic rhinitis, nasal polyp, or adenotonsillar hypertrophy. Rarely, however, these inflammatory symptoms may be associated with more sinister pathology. Recently, we experienced a case of a 4-year-old boy with sinonasal natural killer (NK)/T-cell lymphoma whose initial symptoms were of nasal obstruction and mucopurulent nasal discharge.