Nasal NK/T-cell lymphoma is a rare clinicopathological entity, formerly called midline lethal granuloma. Following progress in histology and the routine use of immunohistochemistry, nasal NK/T-cell lymphoma was recognized as a distinct entity by WHO in 2001.

The authors report the case of a 22-year-old, insulin-dependent diabetic woman, who presented with mid-facial inflammatory swelling following facial trauma, initially diagnosed and treated as cellulitis of the face. The subsequent course was rapidly progressive and fatal, with the development of midline destructive disease. Histological examinations concluded on NK/T-cell lymphoma.

The various differential diagnoses of NK/T-cell lymphoma include gangrenous cellulitis, invasive mycotic rhinosinusitis, Wegener's granulomatosis, actinomycosis, and facial T-cell lymphoma. The clinical presentation of this case was atypical, resulting in delayed diagnosis and treatment. Treatment is based on radiotherapy and chemotherapy, but the prognosis remains very poor even when treatment is rapidly initiated.