Extranodal natural killer (NK) cell/T-cell lymphoma, nasal type, (ENKL) is an aggressive peripheral T-cell lymphoma with an historic median survival of less than 2 years. An analysis of the SEER database from 2001 to 2014 demonstrated 797 occurrences in the United States with a male predominance and a median age at diagnosis of 53 years. The median survival was 20 months across groups, but it varied greatly by stage. The median survival was more than 7 years for early-stage disease compared with only 7 months for stage IV disease. However, survival has improved in the modern era.
This analysis included data from the North American cohort; it was largely composed of white patients, and only 18% of those enrolled were Asian. The cohort included patients with newly diagnosed and relapsed disease, all with central pathology review. The 3‐year PFS and OS rates of the entire group were 28% and 34%, respectively, and all relapses occurred before 2 years. Interestingly, there was no benefit of earlier allo-SCT.
ENKL is a rare T-cell lymphoma caused by infection with EBV. Patients with limited-stage disease are often cured with asparaginase-based chemotherapy and high-dose RT. Unfortunately, those with advanced-stage and relapsed disease often experience an aggressive disease course, and optimal treatment has not been defined. Recent studies have shown promising activity of agents, such as EBV- and LMP-CTLs and checkpoint blockade. We hope that, as the data and science of these approaches mature, they will provide alternative curative approaches, especially for patients with aggressive disease.