Extranodal Natural Killer/T-Cell Lymphoma: An Incidental Finding

Abstract

Extranodal natural killer/T-cell lymphoma (ENKTCL) is a rare form of non-Hodgkin lymphoma. This neoplasm is more prevalent in regions of Asia and Latin America and most commonly involves the sinonasal tract, presenting with signs of nasal obstruction, epistaxis, or sinus infection. It is a locally destructive and angioinvasive neoplasm. The treatment of ENKTCL is dependent on the extent of the tumor. For localized disease, the treatment is chemoradiation. For disseminated disease, treatment is mainly chemotherapy-based. This report describes a case of a 41-year-old Hispanic woman who initially presented with signs of nasal congestion for four weeks and was subsequently diagnosed and treated for chronic sinusitis. The patient underwent endoscopic surgery for persistent chronic sinusitis, with a presumptive diagnosis of allergic fungal rhinosinusitis based on clinical and radiographic presentation. The pathologic exam revealed a diagnosis of ENKTCL. The patient underwent three cycles of chemotherapy comprised of steroid (hydrocortisone), methotrexate, ifosfamide, pre-asparaginase, and etoposide (SMILE) followed by radiation, resulting in clinical and radiographic remission. On review of the literature, ENKTCL is very rare in the United States and diagnosis is commonly delayed due to non-specific signs. We report this case to increase awareness of this disease entity and remind clinicians to include this in the differential diagnosis of nasal obstruction.

Keywords: endoscopic sinus surgery; epstein-barr virus (ebv); extra-nodal nk/t-cell lymphoma; nasal tumor; sinusitis; smile regimen.

Figure 1. Complete opacification of the left frontal sinus

Figure 2. Opacification of the left maxillary sinus and nasal cavity with double density sign (arrow)

Figure 3. Extension of disease through nasal cavity into the nasopharynx

Figure 4. Large atypical cells with irregular nuclear contours, vesicular chromatin, multiple nucleoli, and clear cytoplasm completely effacing the lymph node architecture

Figure 5. EBV by Epstein-Barr virus-encoded small RNAs in situ hybridization; cells are diffusely positive

EBV: Epstein-Barr virus; RNA: ribonucleic acid

Figure 6. No residual disease noted after completion of treatment