NK T-cell lymphoma is an aggressive type of cancer that attacks the natural killer cells and/or T-cells used by the immune system to fight viruses, bacteria, and tumor cells. This disease is also known as nasal type NK lymphoma, anglocentric lymphoma, or extranodal natural killer cell lymphoma. Rare in the United States, this form of non-Hodgkins lymphoma primarily affects people of Asian or Latin American decent. It is sometimes associated with the Epstein-Barr virus.
The NK in NK T-cell lymphoma stands for natural killer cells. These are categorized as belonging to a group of white blood cells known as lymphocytes that attack viruses and tumor cells, often found in the nasal or paranasal cavity. As of 2011, medical research had yet to determine whether NK T-cell lymphoma is caused by the destruction of natural killer cells or T-cells. T-cells, like NK cells, are lymphocytes that help maintain healthy cell function. In either case, the cells become malignant.
The term extranodal indicates that the lymphoma occurs outside of the lymph nodes. Symptoms will present in the nasal or sinus cavity in most cases, but symptoms can appear in other extranodal areas such as the trachea, on the skin, and in the gastrointestinal tract. Symptoms of NK T-cell lymphoma can include necrosis in the nasal cavity leading to nose bleeds, masses in the nasal or sinus cavity, skin ulcers, and perforations in the gastrointestinal tract. A biopsy is needed to diagnose the disease. Due to the rarity of this condition, some doctors may utilize additional technological supports such as x-rays, PET scans, CT scans, or ultrasounds to help confirm the diagnosis.
Treatments for NK T-cell lymphoma are still being researched. The most common treatment is the chemotherapy CHOP regimen, named for the four drugs utilized: cyclophosphamide, hydroxydoxorubicin, Oncovin®, and prednisone. The CHOP regimen is administered in four-week cycles, often repeated as many as six times. A combination of radiation and chemotherapy is sometimes recommended. Many doctors recommend an aggressive treatment due to the typically fast growth rate of the disease.
NK T-cell lymphoma was discovered and labeled as a unique lymphoma in 1994. The general nature of the symptoms and the fact that some symptoms occur outside the nasal region led to varying categorizations and confusion of the disease throughout the late 1990s. This variety of conflicting information resulted in a slower time line in researching the disease.