Extranodal NK/T-cell lymphoma, nasal type: Clinical features, outcome, and prognostic factors in 101 cases

We aimed to define the clinical features, outcome, and prognostic factors for extranodal NK/T-cell lymphoma (ENKTL) patients in Taiwan.

We retrospectively reviewed 101 ENKTL patients diagnosed between February 1998 and October 2015.

The median age of 101 patients was 52 years old (range 22-85); 76.2% of patients were Ann Arbor stage I/II disease. The 5-year progression-free survival (PFS) and overall survival (OS) were 49.9% and 54.8%, respectively. Patients with log[EBV-DNA] ≥ 3.8 and bone marrow hemophagocytosis at diagnosis had inferior PFS and OS. Most stage I/II patients received combined chemoradiotherapy with anthracycline-containing regimen, with overall response rate of 96.7%, complete response rate 86.9%, 5-year PFS 65%, and OS 72%. The relapse rate was 29.3% with a short median disease-free survival of 6.2 months. In advanced stage patients, overall response rate was only 13.6%, with median PFS 2.3 months, and OS 4.8 months. Age ≥ 60 (HR 3.773, 95% CI 1.733-8.215, P = 0.001) and stage III/IV (HR 7.785, 95% CI 2.312-26.213, P = 0.001) were unfavorable prognostic factors for PFS and OS by multivariate analyses.

Age ≥ 60 and stage III/IV are independent poor prognostic factors for PFS and OS. Early-stage ENKTL patients had good response to combined chemoradiotherapy with anthracycline-containing regimen but with a high relapse rate and short disease-free survival. Anthracycline-containing regimen in advanced stage had poor response and dismal outcome.