Abstract
The frequency and significance of programmed cell death ligand (PD-L) 2 expression in diffuse large B cell lymphoma (DLBCL) remain undefined. We described the expression pattern of PD-L/PD-1 in 88 DLBCL patients using immunohistochemistry. The association between PD-L expression and clinical characteristics/outcomes were analyzed. PD-L1 and PD-L2 were expressed in 14.8% and 68.2% of DLBCL patients with median positivity on tumor cells of 100% and 90%, respectively. PD-1 on tumor-infiltrating lymphocytes (TILs) was expressed in 12.5% of patients. Interestingly, 45.5% of patients had PD-L2 expressing TILs which were significantly associated with bulky disease (p = .046) and elevated lactate dehydrogenase (p = .048). PD-L1 and/or PD-L2 expression on lymphoma cells was associated with inferior progression-free survival (Hazard ratio [HR] 2.20; 95% Confidence Interval [CI] 1.004–4.84, p = .049) and overall survival (HR 2.27; 95%CI 1.03–4.98, p = .042), using multivariate analysis. In summary, PD-L2 expression on DLBCL is common and, together with PD-L1, were related to poor outcomes.
Acknowledgements
We would like to express our profound gratitude to Mr. Preecha Reaungwechworrachai and administrative staff of the Department of Pathology who helped us retrieve the specimens, prepared, and stained the specimens.
Disclosure statement
All authors report no conflict of interest.