Non-Hodgkins lymphoma of the nasal cavity: A case report.

We present a rare case of an 81-year-old woman presenting with acute left nasal blockage caused by a large nasal mass of unknown origin. The mass was subsequently diagnosed as diffuse large B-cell non-Hodgkin lymphoma (NHL). Nasal/paranasal space involvement in NHL is uncommon, representing only 0.2%-2% of cases. In this case, the nasal NHL mass exhibited a favorable prognosis, in contrast to previously reported sinonasal lymphomas with poor outcomes. The patient underwent excisional biopsy and was treated with 3 cycles of R-CHOP chemotherapy, resulting in complete resolution of the mass confirmed by a follow-up CT scan and no signs of disease after 1 year. Differentiating sinonasal lymphomas from other neoplasms can be challenging due to their variable morphology and location. Diffuse presentations of sinonasal lymphoma can aid in distinguishing them from discrete lesions associated with other sinonasal neoplasms. However, differentiation from acute invasive sinonasal infection remains difficult. MRI can help identify lymphomas through the characteristic hypointense T2 signal and diffusion restriction, with the combined use of CT to aid in differentiating masses of unknown morphology. Nonetheless, squamous cell carcinoma, which mimics lymphoma features on MRI, poses additional challenges to accurate identification. This case highlights the rarity of nasal NHLs, their potential for excellent prognosis, and the importance of diverse imaging techniques in their diagnosis and differentiation from other sinonasal pathologies.