Γδ and Αβ T-Cell Large Granular Lymphocytic Leukemia Have Similar Characteristics and Outcomes

• Published in: Blood 2024-11, Vol.144 (Supplement 1), p.1678-1678
• Main Authors: Yuxi, Li, Cui, Rui, Yu, Ying, Huang, Yanshan, Sun, Jingwen, Yan, Yuting, Wang, Tingyu, Wenjie, Xiong, Lyu, Rui, Wang, Qi, LIU, Wei, An, Gang, Sui, Weiwei, Xu, Yan, Huang, Wenyang, Zou, Dehui, Zhang, Fengkui, Wang, Huijun, Xiao, Zhi-jian, Qiu, Lu-Gui, Yi, Shuhua
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2024-202457

Introduction Large granular lymphocytic leukemia (LGLL) is a rare chronic lymphoproliferative disorder characterized by persistent clonal expansions of lymphocytes over an extended period in which nearly 80% of cases are T-cell large granular lymphocytic leukemia (T-LGLL) (Alaggio et al. 2022). The clinical and biological features of T-LGLL exhibit significant heterogeneity as it can manifest as either CD8+ or CD4+. Furthermore, T-LGLL is associated with the rearrangement of the T cell receptor (TCR), which can be categorized into αβ T-LGLL and γδ T-LGLL variants. Additionally, few studies have compared αβ T-LGLL and γδ T-LGLL displaying that γδ T-LGLL revealed a similar or more aggressive clinical manifestation than αβ T-LGLL (Bourgault-Rouxel et al. 2008; Sandberg et al. 2006; Barilà et al. 2020; Barila et al. 2023). Thus, in this study, we described the clinical and biological features of 56 γδ T-LGLL patients, comparing to 306 αβ T-LGLL patients from a single institute. Methods A total of 362 patients with a diagnosis of T-LGLL between July 2005 and July 2022 from the Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Science. All the patients met the recommended diagnostic criteria for LGLL(Lamy, Moignet, and Loughran 2017). We conducted a retrospective analysis of patients' clinical data, laboratory examinations, treatment, and follow-up. Non-normal distribution data were expressed as a median and range. Comparisons of continuous variables in different subgroups were analyzed with the Mann-Whitney U test. A χ2 or Fisher exact test was used to compare categorical variables. OS and PFS was calculated using the Kaplan-Meier method and compared by the log-rank test. P value < 0.05 was considered significant. Follow-up was to death or all statistical analyses were performed using the statistical software SPSS 27. Results Out of the 362 consecutive patients identified with T-LGLL, 56 (7.5%) were γδ T-LGLL, while 306 (92.5%) were αβ T-LGLL. Overall, clinical findings were very similar between the two groups in terms of median age (55 vs 54, P = 0.536), sex ratio (1.2 vs 1.3, P = 0.543), severity of neutropenia [absolute neutrophil count (ANC) ≤ 1.5×109 /L: 53.5% vs 53.3%, P = 0.959], anemia [hemoglobin (HB) ≤ 120 g/L: 85.7% vs 79.4%, P = 0.275], thrombocytopenia [Platelet (PLT) ≤ 100×109 /L: 14.3% vs 15.4%, P = 0.837], splenomegaly (32.7% vs 37.6%, P = 0.497), and pure red blood cell aplastic anemia (32.1% vs 39.9%, P = 0.275). Ad