Extranodal NK/T-cell lymphoma is an aggressive lymphoma that typically affects the nasal cavity and upper aerodigestive structures representing the most common T-cell lymphoma subtype in Asia and in some regions of Central and South America. EBV infection is believed to play an important role in this neoplasm since it is present in virtually all cases. Male adults with a median age of 46–60 years are the most affected group and patients are more often diagnosed with nasal obstruction, with discharge or epistaxis, followed by edema and ulceration. The occurrence of a diffuse edema of the lower eyelid is a frequent manifestation. The highly aggressive clinical evolution of the disease leads to a necrotic destruction of nasal skin and mucosa, nasal septum, paranasal sinuses and nasopharynx, frequently perforating the central part of the palate, and leading to an oroantral communication. Histologically, this lymphoma shows a diffuse proliferation of small to large neoplastic cells, with extensive areas of necrosis and blood vessels surrounded by neoplastic cells, which are positive for CD3ε, CD45RO, granzyme, and CD56 in most of the cases. Patients’ prognosis is still poor, despite improvements with the use of non-anthracycline-containing regimens based on platinum or L-asparaginase.