Clinical characteristics and survival analysis of extra-upper aerodigestive tract extranodal NK/T-cell lymphoma

Fei QI; Mei DONG

ABSTRACT

Objective:

To analyze the clinical characteristics, survival outcome and prognostic factors of patients with extra-upper aerodigestive tract extranodal NK/T-cell lymphoma (EUADT-ENKTCL).

Methods:

We collected the clinical data of 779 patients with ENKTCL who were registered in SEER (Surveillance, Epidemiology, and End Results) database from 2000 to 2015 including 622 cases diagnosed with upper-aerodigestive tract extranodal NK/T-cell lymphoma (UADT-ENKTCL) and 157 cases with EUADT-ENKTCL. Clinical characteristics, survival outcome and prognostic factors were analyzed in EUADT-ENKTCL patients.

Results:

The median age of patients with EUADT-ENKTCL was 55. The ratio of male to female was 1.85∶1. Compared with UADT-ENKTCL, patients with EUADT-ENKTCL accounted a higher proportion of malignant T-cell origin ( χ2=18.916, P<0.001), advanced stage disease ( χ2=63.669, P<0.001), accompanied B symptoms ( χ2=14.657, P=0.001) and receiving chemotherapy alone ( χ2=71.412, P<0.001). EUADT-ENKTCL could be originated in different organs and tissues throughout the body, among which the skin or subcutaneous soft tissues was the most common locations (38.2%, 60/157), followed by gastrointestinal tract (18.5%, 29/157), lung/pleura (13.4%, 21/157), testis (6.4%, 10/157), orbit (5.1%, 8/157) and others. The median overall survival (OS) was 8.0 months and 5-year OS rate was 24.0% for the EUADT-ENKTCL cohort, which were much inferior to those of UADT-ENKTCL patients (31.0 months and 43.5%; χ2=32.080, P<0.001). Univariate analysis showed that patients with advanced stage or primary lung disease of EUADT-ENKTCL had unfavorable OS. Stage was a prognostic factor of OS via multivariate analysis (Ⅲ/Ⅳ vs. Ⅰ/Ⅱ, HR=2.078, 95% CI 1.335-3.234, P=0.001).

Conclusion:

EUADT-ENKTCL is a highly aggressive malignancy. Compared with UADT-ENKTCL, EUADT-ENKTCL patients have different clinical characteristics and significantly inferior OS.