Classification of NK-large granular lymphocytic leukemia by CD56 expression
Yuxi Li, Rui Cui, Ying Yu, Yanshan Huang, Yuting Yan, Jingwen Sun, Jingjing Yuan, Tingyu Wang, Rui Lyu, Wenjie Xiong, Qi Wang, Wei Liu, Gang An, Weiwei Sui, Yan Xu, Wenyang Huang, Liang Wang, Dehui Zou, Fengkui Zhang, Huijun Wang, Lugui Qiu, Shuhua YiAbstract
NK-large granular lymphocytic leukemia (NK-LGLL) is a rare chronic lymphoproliferative disorder and displays heterogeneity that remains insufficiently defined. CD56 plays a pivotal role in NK-cell maturation linked to cytotoxicity. However, whether CD56 might be associated with distinctive characteristics in NK-LGLL has not been determined. Hence, this study aims to explore potential associations between CD56 and clinical and biological features in 47 patients with NK-LGLL. Above all, anemia (57.4%) was the most prevalent symptom. Patients treated with immunosuppressive therapy showed a favorable outcome with 87.0% achieving remission. Furthermore, when stratifying patients by CD56 expression on tumor cells, the subset of 28 patients (59.6%) with diminished CD56 expression was frequently relevant to symptomatic disease (92.9% vs 15.8%, P < .001), comprising anemia (85.7% vs 15.8%, P < .001), neutropenia (67.9% vs 0.0%, P < .001), and splenomegaly (42.9% vs 10.5%, P = .024). Additionally, this subset demonstrated exclusive STAT3 mutation (61.9% vs 0.0%, P = .003), elevated CD161 levels (54.5% vs 0.0%, P < .001), and bone marrow fibrosis (92.3% vs 50.0%, P = 0.006). Furthermore, they showed shorter time to first treatment (TTFT) (4-year TTFT: 66.7% vs 100.0%, P = .083) and first-line progression-free survival (PFS) (median PFS: 26.3 months vs not reached, P = .112). Overall, our data indicate that NK-LGLL patients with diminished CD56 expression represent a more aggressive subset compared to those with normal CD56 levels, underscoring the significance of CD56 as a potential prognostic marker and advancing our understanding of the underlying pathogenesis of NK-LGLL.